Stroke Length & CHO Useage



A

Aw

Guest
Two swimmers, identical in size, strength, and overall swimming ability compete in an iron distance
triathlon. Neither wears a wetsuit. Both complete the swim, 3.9k or 4,225 yds, in 55 minutes.
Swimmer A swims with a long-forward, FQS stroke, and averages 2.50 meters per complete stroke cycle
(1.25m/hand splash). Swimmer B swims with a short, constant-pressure, kayak stroke and averages 1.75
meters per complete stroke cycle. Both employ a minimal kick, and both breath every stroke.

Which swimmer generates higher *peak* power during each stroke cycle? That' s easy; swimmer A. The
long-stroke swimmer covers a much greater distance with fewer strokes.

Which swimmer uses more carbs during the swim? Swimmer A; the long-stroke swimmer burns more
carbs in order to generate that higher peak power during each cycle. Swimmer B, the constant-
pressure swimmer, conserves momentum throughout the stroke cycle by maintaining a rapid, carb-
efficient cadence.

Long-stroke, FQS swimmer A.think fast-twitch carb-eater.

Short-stroke, constant-pressure swimmer B.think slow-twitch fat-burner.

Which swimmer hits the wall at mile 23 of the run because they weren't able replace those precious
carbs they wasted during the swim? Swimmer A; the long-stroke swimmer bonks.

I know, I know; you're going to tell me that the long-stroke swimmer, swimmer A, doesn't achieve
higher peak power during a given stroke cycle. You're going to tell me that swimmer A has less drag
and therefore can cover the same distance as swimmer B, but with fewer strokes and less power. I
don't buy it.

Tether swimmers A & B with stretch cord. Don't allow them to kick, and make them swim as far and as
fast as they can for 1 minute. Both will achieve the same average distance. Swimmer B, the constant
pressure, fat-burning swimmer, will max out on distance and hold steady. Even though Swimmer A, the
carb-burning, long-stroke, FQS swimmer will achieve the same *average* distance, he or she will
bounce repeatedly a little ahead of swimmer A & then get pulled behind.repeat, repeat, repeat. In
other words, swimmer A is unable to maintain a fixed position in the water. So, who's generating
higher peak power during each stroke cycle???

What are the implications of all this? Triathletes competing in long-course & ultra-distance (1/2
and iron distance) triathlon would be well advised to adopt a short-stroke, constant pressure, rapid
cadence freestyle. I'd have to say the same for open-water and postal swimmers competing in events
longer than 5k. I doesn't makes a hill of beans worth of difference with respect to middle distance
swimmers or sprinters.

By the way, you could probably duplicate the tethered swim test with a flume or a weighted swim-
lift. What's interesting is to observe what happens to FQS swimmers when they're tethered or when
they swim in an endless pool. They do one of two thing. They increase significantly their kick in
order to maintain their postion during the "dead spots" in their stroke, or they shorten their
stroke. The longer they swim, the shorter their stroke becomes until they're no longer
*bouncing*. They learn to kayak in order to maintain a fixed position in the water; ie., in order
to conserve momentum.

Thoughts?????
 
D

Drclean

Guest
Sorry to top post but this is tool ong for bottom posting.

First thought unfortunately - total garbage.

Neither swimmer will use fast twitch muscle fibres for any length of time - it's just not possible
to sustain that efort. In reality swimmer B is more likely to use a geater proportion of fast twitch
because of his increased cadence due to his shorter stroke.

The reason the swimmer A produces a longer distance per stroke is purely because of his stroke
length - not because he produces more power.

Your conclusions are consequently false I'm afraid.
--
DrClean
www.DrClean.co.uk
The Best Fabric Cleaning Resource on the Web

"AW" <[email protected]> wrote in message
news:[email protected]...
> Two swimmers, identical in size, strength, and overall swimming ability
> compete in an iron distance triathlon. Neither wears a wetsuit. Both
> complete the swim, 3.9k or 4,225 yds, in 55 minutes. Swimmer A swims with
a
> long-forward, FQS stroke, and averages 2.50 meters per complete stroke
cycle
> (1.25m/hand splash). Swimmer B swims with a short, constant-pressure,
kayak
> stroke and averages 1.75 meters per complete stroke cycle. Both employ a
> minimal kick, and both breath every stroke.
>
>
>
> Which swimmer generates higher *peak* power during each stroke cycle?
That'
> s easy; swimmer A. The long-stroke swimmer covers a much greater distance
> with fewer strokes.
>
>
>
> Which swimmer uses more carbs during the swim? Swimmer A; the long-stroke
> swimmer burns more carbs in order to generate that higher peak power
during
> each cycle. Swimmer B, the constant-pressure swimmer, conserves momentum
> throughout the stroke cycle by maintaining a rapid, carb-efficient
cadence.
>
>
>
> Long-stroke, FQS swimmer A.think fast-twitch carb-eater.
>
>
>
> Short-stroke, constant-pressure swimmer B.think slow-twitch fat-burner.
>
>
>
> Which swimmer hits the wall at mile 23 of the run because they weren't
able
> replace those precious carbs they wasted during the swim? Swimmer A; the
> long-stroke swimmer bonks.
>
>
>
> I know, I know; you're going to tell me that the long-stroke swimmer,
> swimmer A, doesn't achieve higher peak power during a given stroke cycle.
> You're going to tell me that swimmer A has less drag and therefore can
cover
> the same distance as swimmer B, but with fewer strokes and less power. I
> don't buy it.
>
>
>
> Tether swimmers A & B with stretch cord. Don't allow them to kick, and
make
> them swim as far and as fast as they can for 1 minute. Both will achieve
> the same average distance. Swimmer B, the constant pressure, fat-burning
> swimmer, will max out on distance and hold steady. Even though Swimmer A,
> the carb-burning, long-stroke, FQS swimmer will achieve the same *average*
> distance, he or she will bounce repeatedly a little ahead of swimmer A &
> then get pulled behind.repeat, repeat, repeat. In other words, swimmer A
is
> unable to maintain a fixed position in the water. So, who's generating
> higher peak power during each stroke cycle???
>
>
>
> What are the implications of all this? Triathletes competing in
long-course
> & ultra-distance (1/2 and iron distance) triathlon would be well advised
to
> adopt a short-stroke, constant pressure, rapid cadence freestyle. I'd
have
> to say the same for open-water and postal swimmers competing in events
> longer than 5k. I doesn't makes a hill of beans worth of difference with
> respect to middle distance swimmers or sprinters.
>
>
>
> By the way, you could probably duplicate the tethered swim test with a
flume
> or a weighted swim-lift. What's interesting is to observe what happens to
> FQS swimmers when they're tethered or when they swim in an endless pool.
> They do one of two thing. They increase significantly their kick in order
to
> maintain their postion during the "dead spots" in their stroke, or they
> shorten their stroke. The longer they swim, the shorter their stroke
> becomes until they're no longer *bouncing*. They learn to kayak in order
to
> maintain a fixed position in the water; ie., in order to conserve
momentum.
>
>
>
> Thoughts?????
 
J

Jordi Bataller

Guest
IMHO

Higher stroke length is positive if as a result primarily of efficiency, not of using more power.

Also it seems that a constant speed si desirable but a constant arm movement may (for some swimmers)
exhaust arm muscles, while an arm cadence of pull + glide (i.e: effort + rest ) may benefit some
other swimmers.

Everyone must seek its *personal* right combination.

Jordi Bataller
 
M

MJuric

Guest
On Fri, 06 Feb 2004 07:39:38 GMT, "AW" <[email protected]> wrote:

>Two swimmers, identical in size, strength, and overall swimming ability compete in an iron distance
>triathlon. Neither wears a wetsuit. Both complete the swim, 3.9k or 4,225 yds, in 55 minutes.
>Swimmer A swims with a long-forward, FQS stroke, and averages 2.50 meters per complete stroke cycle
>(1.25m/hand splash). Swimmer B swims with a short, constant-pressure, kayak stroke and averages
> 1.75 meters per complete stroke cycle. Both employ a minimal kick, and both breath every stroke.
>
>
>
>Which swimmer generates higher *peak* power during each stroke cycle? That' s easy; swimmer A. The
>long-stroke swimmer covers a much greater distance with fewer strokes.
>
>
>
>Which swimmer uses more carbs during the swim? Swimmer A; the long-stroke swimmer burns more
>carbs in order to generate that higher peak power during each cycle. Swimmer B, the constant-
>pressure swimmer, conserves momentum throughout the stroke cycle by maintaining a rapid, carb-
>efficient cadence.

From a simple physics point of view it would be very hard to convince me that either swimmer
is using more than the other. All things equal the same distance is covered in the same time
so teh same amount of work was done. Thus the same amount of energy was consumed. Even
considering peaks and valleys the overall average must be the same. Your above assumption
that a long stroke creates a "higher peak" power seems a bit "all encompising" to me.
Recently discussion has surround the idea of one peak and two peak strokes. Seems to me it
woudl be possible to ahve a long stroke that was a two peak stroke and have a lower "peak"
than a single peak short stroke.

>
>
>
>Long-stroke, FQS swimmer A.think fast-twitch carb-eater.
>
>
>
>Short-stroke, constant-pressure swimmer B.think slow-twitch fat-burner.

Again based on the high peak assumption of the longer stroke. Even if the longer stroke does
pass over into a higher peak, in order to maintain the slower speed the swimmer must have an
equal amount of time below that of the high stroke swimmer. Following the same thought
process that mean they are burning less carbs at that point, again averaging out.

>
>
>
>Which swimmer hits the wall at mile 23 of the run because they weren't able replace those precious
>carbs they wasted during the swim? Swimmer A; the long-stroke swimmer bonks.
>
>
>
>I know, I know; you're going to tell me that the long-stroke swimmer, swimmer A, doesn't achieve
>higher peak power during a given stroke cycle. You're going to tell me that swimmer A has less drag
>and therefore can cover the same distance as swimmer B, but with fewer strokes and less power. I
>don't buy it.
>
>
>
>Tether swimmers A & B with stretch cord. Don't allow them to kick, and make them swim as far and as
>fast as they can for 1 minute. Both will achieve the same average distance. Swimmer B, the constant
>pressure, fat-burning swimmer, will max out on distance and hold steady. Even though Swimmer A, the
>carb-burning, long-stroke, FQS swimmer will achieve the same *average* distance, he or she will
>bounce repeatedly a little ahead of swimmer A & then get pulled behind.repeat, repeat, repeat. In
>other words, swimmer A is unable to maintain a fixed position in the water. So, who's generating
>higher peak power during each stroke cycle???

Again highly speculative and most assureadly different from swimmer to swimmer.

>
>
>
>What are the implications of all this? Triathletes competing in long-course & ultra-distance (1/2
>and iron distance) triathlon would be well advised to adopt a short-stroke, constant pressure,
>rapid cadence freestyle. I'd have to say the same for open-water and postal swimmers competing in
>events longer than 5k. I doesn't makes a hill of beans worth of difference with respect to middle
>distance swimmers or sprinters.
>
>
>
>By the way, you could probably duplicate the tethered swim test with a flume or a weighted swim-
>lift. What's interesting is to observe what happens to FQS swimmers when they're tethered or when
>they swim in an endless pool. They do one of two thing. They increase significantly their kick in
>order to maintain their postion during the "dead spots" in their stroke, or they shorten their
>stroke. The longer they swim, the shorter their stroke becomes until they're no longer *bouncing*.
>They learn to kayak in order to maintain a fixed position in the water; ie., in order to conserve
>momentum.
>
>
>
>Thoughts?????
>

I suspect that the amount of Carbs burned by different style of strokes, everything else
equal, is so minimal that its effect on ones race is to be minimal, if noticeable. Certainly
not enough to cause one to hit the wall or not, which in any case is much more likely to be
caused by a plethora of other factors prior to swim stroke style. This as with many other
issues discussed her frankly have very little bearing on the average swimmer, and more than
likely have little effect on anyone but the elites that are on the extremes of the above
examples. In my experiance most all of us mere mortals have much more influencing factors to
worry about than such things. Maybe just putting in the yardage for example, or figuring out
a way to get our hips to ride a bit higher in the water.

~Matt
 
M

Mark P

Guest
AW wrote:
> Two swimmers, identical in size, strength, and overall swimming ability compete in an iron
> distance triathlon. Neither wears a wetsuit. Both complete the swim, 3.9k or 4,225 yds, in 55
> minutes. Swimmer A swims with a long-forward, FQS stroke, and averages 2.50 meters per complete
> stroke cycle
> (1.25m/hand splash). Swimmer B swims with a short, constant-pressure, kayak stroke and averages
> 1.75 meters per complete stroke cycle. Both employ a minimal kick, and both breath every
> stroke.
>
>
>
> Which swimmer generates higher *peak* power during each stroke cycle? That' s easy; swimmer A. The
> long-stroke swimmer covers a much greater distance with fewer strokes.
>

You should look up the definition of power. It's work/time not work/stroke. Moreover, even if you
did want to talk about work/stroke, the "longer" stroker isn't necessarily doing more work. He could
simply be swimming more efficiently.
 
R

Rtk

Guest
MJuric wrote:

> From a simple physics point of view it would be very hard to convince me that either swimmer
> is using more than the other. All things equal the same distance is covered in the same time
> so teh same amount of work was done. Thus the same amount of energy was consumed.

I promised the physicist outside shoveling snow so deep they closed the whole university including
the pool that I would help shovel if he would just say if the above is true or false.

He says: True (in more words than I want to type).

Ruth Kazez

p.s. You know how you can tell an accused person any lie to get him to tell you where the body is?
Good idea. I'm not really going to help shovel all that stuff.
 
R

Rtk

Guest
MJuric wrote:

> From a simple physics point of view it would be very hard to convince me that either swimmer
> is using more than the other. All things equal the same distance is covered in the same time
> so teh same amount of work was done. Thus the same amount of energy was consumed.

I promised the physicist outside shoveling snow so deep they closed the whole university including
the pool that I would help shovel if he would just say if the above is true or false.

He says: True (in more words than I want to type).

Ruth Kazez

p.s. You know how you can tell an accused person any lie to get him to tell you where the body is?
Good idea. I'm not really going to help shovel all that stuff.
 
A

Andres Muro

Guest
Hi, I can try to reflect on these two positions, cause I am experimenting on my stroke. When I swim
with a shorter stroke, I get what seemes like a faster heart rate, but just barely, With the longer
stroke, if I hold it too long, I may experience shortness of breath. I could swim with both the long
and the short stroke and go forever w/o getting tired and w/o going near AT. I have gotten it to a
point that doing the longer stroke, I can do it fast enough that I get enough air. When I do this, I
am certainly swimming faster and more efficient than with my shorter stroke and hence getting less
tired. With neither stroke I expend too much energy with the pull. I try to keep my pull as relaxed
as possible. If I dig hard, then I'll spend way more energy with the longer stroke. It feels like
lifting weights to me. However, I move way faster.

So, for me personally, I prefer the longer stroke. However, I've seen shorter strokers that kick
ass. So, it boils doewn to a matter of preference.

With running and biking, you'll also get the same dilema. spin, or push, fast turnover or long
reach? Hinault and lemond were smashers. Indurain and Armstrong are spinners. There are theories
that favor one approach over the other. I say, experiment and adapt to your body type.

I buy the long stretch style of recommended by Terry Laughling, but I don't beleive in pushing
down my bouy or looking straight down. I beleive in arching my back and looking in a 45 degree
angle, more like Larry's model. So, I say, listen to all theories. try them all, and use what
works for you.

I can swim bilaterally no problem. However, if I try to swim bilaterally for more than 100 yards,
I'll die for lack of oxigen. So, for me personally I need to breath with every stroke. Yet, I've
seen people breathing bilaterally w/o problems.

Andres

"AW" <[email protected]> wrote in message news:<[email protected]>...
> Two swimmers, identical in size, strength, and overall swimming ability compete in an iron
> distance triathlon. Neither wears a wetsuit. Both complete the swim, 3.9k or 4,225 yds, in 55
> minutes. Swimmer A swims with a long-forward, FQS stroke, and averages 2.50 meters per complete
> stroke cycle
> (1.25m/hand splash). Swimmer B swims with a short, constant-pressure, kayak stroke and averages
> 1.75 meters per complete stroke cycle. Both employ a minimal kick, and both breath every
> stroke.
>
>
>
> Which swimmer generates higher *peak* power during each stroke cycle? That' s easy; swimmer A. The
> long-stroke swimmer covers a much greater distance with fewer strokes.
>
>
>
> Which swimmer uses more carbs during the swim? Swimmer A; the long-stroke swimmer burns more carbs
> in order to generate that higher peak power during each cycle. Swimmer B, the constant-pressure
> swimmer, conserves momentum throughout the stroke cycle by maintaining a rapid, carb-efficient
> cadence.
>
>
>
> Long-stroke, FQS swimmer A.think fast-twitch carb-eater.
>
>
>
> Short-stroke, constant-pressure swimmer B.think slow-twitch fat-burner.
>
>
>
> Which swimmer hits the wall at mile 23 of the run because they weren't able replace those precious
> carbs they wasted during the swim? Swimmer A; the long-stroke swimmer bonks.
>
>
>
> I know, I know; you're going to tell me that the long-stroke swimmer, swimmer A, doesn't achieve
> higher peak power during a given stroke cycle. You're going to tell me that swimmer A has less
> drag and therefore can cover the same distance as swimmer B, but with fewer strokes and less
> power. I don't buy it.
>
>
>
> Tether swimmers A & B with stretch cord. Don't allow them to kick, and make them swim as far and
> as fast as they can for 1 minute. Both will achieve the same average distance. Swimmer B, the
> constant pressure, fat-burning swimmer, will max out on distance and hold steady. Even though
> Swimmer A, the carb-burning, long-stroke, FQS swimmer will achieve the same *average* distance, he
> or she will bounce repeatedly a little ahead of swimmer A & then get pulled behind.repeat, repeat,
> repeat. In other words, swimmer A is unable to maintain a fixed position in the water. So, who's
> generating higher peak power during each stroke cycle???
>
>
>
> What are the implications of all this? Triathletes competing in long-course & ultra-distance (1/2
> and iron distance) triathlon would be well advised to adopt a short-stroke, constant pressure,
> rapid cadence freestyle. I'd have to say the same for open-water and postal swimmers competing in
> events longer than 5k. I doesn't makes a hill of beans worth of difference with respect to middle
> distance swimmers or sprinters.
>
>
>
> By the way, you could probably duplicate the tethered swim test with a flume or a weighted swim-
> lift. What's interesting is to observe what happens to FQS swimmers when they're tethered or when
> they swim in an endless pool. They do one of two thing. They increase significantly their kick in
> order to maintain their postion during the "dead spots" in their stroke, or they shorten their
> stroke. The longer they swim, the shorter their stroke becomes until they're no longer *bouncing*.
> They learn to kayak in order to maintain a fixed position in the water; ie., in order to conserve
> momentum.
>
>
>
> Thoughts?????
 
L

Larry Weisentha

Guest
Interesting speculations.

Some data first.

Swimmers burn negligible fat. Costill compared swimmers, runners, and cyclists. Each swam, ran, or
cycled at 70% VO2 max (just sub-lactate threshold) for 40 minutes. Swimmers emerged borderline
hypoglycemic, with negligible products of fat metabolism circulating in their bloodstream. Cyclists
and runners had significantly higher blood sugar and had copious products of fat metabolism
circulating in their bloodstream. Costill repeated the experiment, with triathletes doing each of
the disciplines. Same result.

This is consistent with what is known about upper body muscle versus lower body muscle (from muscle
biopsy studies on cross country skiers, which use upper and lower bodies to approximately equal
extent, in terms of percent max). Lower body muscle is more "red" muscle-like. More capillaries,
mitochondria, myoglobin (required for fat metabolism). Upper body more "white" muscle-like. Fewer of
the "big 3" (c,m,m) required for fat metabolism. Also, when X-C skiers move from a sedentary
condition to a training state, there is an earlier and greater increase in the "big 3," than in the
case of the upper body. (These were biopsies of quadriceps and triceps, respectively). This is my
turkey muscle vs duck muscle analogy.

I don't think that long stroke vs short stroke has a big influence on fat burning, except that if
long stroke is accompanied by continuous and propulsive kicking (which is should be, if the long
stroke style is used by a swimmer who is not very tall and pencil thin), there may be more fat
burning by virtue of involving the lower body (so long as the kicking is in the net lactate
consuming range). However, this will not conserve carbohydrate stores for the bike and run and I
wouldn't expect long stroke vs short stroke to affect late race bonking in a triathlon.

I do think that there is probably a greater per stroke energy cost with long stroking vis a vis
short stroking. A few years back, I used to write about Tim Martin, who was a sub 15 minute 1650
swimmer for Harvard and top 5 NCAA Division I. Tim took > 25 strokes per 25 YARDS! He told me that
he "hardly pulled any water," which is obviously true. I think that, for a non-kicker, a long stroke
style (if swum for speed and not for cosmesis), will have a higher per stroke energy cost, but there
are obviously fewer strokes per race. Generally speaking, however, at a given total level of work,
it is more efficient (bioenergetically) to "smooth out" the power curve, avoiding high peaks of
power application, which can be achieved by stroking more frequently, with less maximal effort,
and/or by kicking (to minimize loss of velocity), and/or by increasing the duration of force
application, through diagonal in/diagonal out (i.e. "two peak") stroke patterns.

I do think that the high cadence/low cadence cycling analogy is valid. Strong kickers may be able to
swim with a long stroke style without incuring a greater peak energy cost (upper body wise). In
national championship level sprint races, ICAR research showed that the championship finalists had
lower peak upper body forces than did non-finalists. One interpretation is that these swimmers had
lower drag. Another interpretation is that they had superior kicks. Or a combination of both.

- Larry
 
O

Olivier

Guest
Larry Weisenthal <[email protected]> a écrit dans le message :
[email protected]

>
> I do think that the high cadence/low cadence cycling analogy is valid

Please find below some interesting article I found on the web. You have to go to
http://www.bsn.com/Cycling/articles/cadence.html if you want to see the figures.

If you measure the optimal cadence (minimizing oxygen consumption for a given power output) for
cycling, you will find something like 60 RPM. [BTW, this gives me an idea to determine your best
Stroke Length / Stroke Ratio. Try different SL / SR ratio _at a given speed_ with a Heart Rate
Monitor, and then see which SL/SR ratio minimizes your average HR.]

Now, the problem is that elite racers spin at 90 RPM.

Assuming they are not stupid, why do they do that?

Let's just cite the conclusion of the article:

"In summary, laboratory studies indicate that experienced cyclists do not use their most economical
or efficient cadences. However, cadences of 90 to 100 rpm are probably beneficial in spite of
decreases in economy and efficiency. The explanation proposed here suggests the use of high rpms
results in a decrease in average pedal force per revolution and leads to the recruitment of fewer
fast-twitch fibers, placing the reliance for muscle power development primarily on the slow-twitch
and intermediate fibers. The advantage to the cyclist is there is less likelihood of a rapid
accumulation of lactic acid, with the resulting decrease in muscle force production."

So, a higher cadence leads (paradoxically) to the use of slow-twitch fibers, instead of fast-twitch,
which are better suited for an enduring effort.

This would be consistent with the fact that long SL / low SR swimmers are sprinter, relying on their
fast-twitch muscles, while long distance swimmers / open water swimmers / triathlete (which are more
like cycling racers, whose effort is many hours long) are better off swimming with a higher SR,
which is less economical but don't build lactic acid.

-- Olivier

Taken from : Cycling Science - Summer 1996 - What Determines The Optimal Cadence?

----------------------------------------------------------------------------
----

What Determines The Optimal Cadence? As the sport of cycling has evolved, training methods have
changed, equipment has been refined, and performances have been enhanced. However, one aspect of
cycling performance has remained relatively unchanged, that is, the freely chosen cadences of
cyclists during training and racing. Few coaches or exercise scientists would argue that cadences of
90 + 5 rpm are typical of those used during world-class performances in road racing or time-
trialing, particularly over level terrain. Furthermore, there are no compelling reasons, either
scientific or popular, that would lead a coach to recommend a significantly lower or higher cadence
to an elite performer. Therefore, the working hypothesis of this article is that cadences in the
range 85 to 95 rpm are optimal for performance. From a scientific point of view the obvious question
of significance is then, "Why are cadences of 85 to 95 rpm, so typical of elite performers during
competition, optimal?" The purpose of this article is to review and examine the multidisciplinary
exercise science literature concerning optimal cadence, present one possible interdisciplinary
explanation for the optimal cadence phenomenon, and address some common generalizations about
cyclists and noncyclists that appear to be incorrect.

A popular explanation for the use of higher cadences is that they are more efficient, with
efficiency being used in the general sense of accomplishing the task with a minimum of effort,
expense, or waste. However, exercise efficiency has several precise definitions that are summarized
in Gaesser and Brooks (1975). They defined and compared four types of efficiency measures with the
goal of identifying the one that best represented human muscular efficiency.

These efficiency measures were 1 ) gross efficiency, the ratio of the work accomplished to energy
expended, that is, the effectiveness of converting chemical energy into mechanical work; 2) net
efficiency, the ratio of the work accomplished to the energy expended above that during rest, that
is, the cost of resting metabolism is subtracted from the denominator in the computation; 3) work
efficiency, the ratio of the work accomplished to the energy expended above that during cycling with
no load, calculated by subtracting from the denominator the cost of moving the legs plus the resting
metabolism, and 4) delta efficiency - the ratio of the change in the power output to the change in
the energy expended at each power output. Gaesser and Brooks observed that at a constant power
output, efficiency decreased as cadence increased, regardless of which definition of efficiency they
used. Both earlier and subsequent studies have also shown that efficiency decreases as cadence
increases at a constant power output (Benedict and Cathcart, 1913; Dickinson, 1929; Garry and
Wishart, 1931; Seabury et al, 1977; Suzuki, 1979). The conclusion from these studies is, from an
efficiency standpoint, higher cadences do not appear to be beneficial to the cyclist. Surprisingly,
the cadences that produce the highest efficiencies are approximately 50 to 60 rpm.

Not all studies report a decline in cycling efficiency as cadence is increased. For example, Faria
et al (1982) found that at a low power output
( 140 W), gross efficiency decreased from 18% to 14% as cadence increased from 68 to 132 rpm; but at
approximately 290 W, gross efficiency remained constant at approximately 22%. Therefore, at
higher power outputs, increases in cadence may not always decrease cycling efficiency. To
explain the difference between their results and previous research, Faria et al. speculated
that the skill level of the subjects may have played a role. Previous studies tended to test
less-skilled riders who may have engaged noncycle-specific muscle groups, especially during
the higher cadences and power outputs, resulting in increased oxygen consumption without any
increase in useful work. Faria et al used experienced cyclists who were familiar with high
cadences and power outputs and, therefore, perhaps their data more appropriately represented
the cycling task. Clearly their data do provide evidence that cyclists are not disadvantaged
via a reduction in efficiency during cycling at a high power output and high cadence.

The issue of cycling efficiency has recently been revisited by Sidossis et al (1992). They found
that gross efficiency was similar at cadences of 60, 80, and 100 rpm during cycling at power outputs
corresponding to 80% (280 W) and 90% (300 W) of an individual's maximal aerobic power (Figure 1).
However, at 50% and 60% of 9&emdash;2 max' the efficiency of 100 rpm was significantly lower than
either 60 or 80 rpm. These data are consistent with Faria et al (1982) and suggest that at high
power outputs, higher cadences are not significantly less efficient compared to lower cadences. In
contrast to Gaesser and Brooks (1975), Sidossis et al also found that delta efficiency increased
from 21% to 24.5% as cadence increased from 60 to 100 rpm (Figure 2). Like Faria et al, they also
suggested that differences between their data and previous work may have been due to the use of
unskilled riders in previous studies who may have recruited muscles that were not cycling specific,
raising oxygen consumption without increasing the amount of useful work done. According to these
authors this possibility makes delta efficiency a more appropriate measure of muscular efficiency
than gross efficiency. To explain the increase in delta efficiency as cadence increased, they
suggested that the lower extremity muscles responsible for meeting the power output demands of the
task may have been closer to the speed of shortening that maximized muscular efficiency (i.e., a
speed of approximately 1/3 of the maximal speed of shortening in individual muscle fibers). It
should also be noted that both Faria et al and Sidossis et al used power outputs that were
considerably higher than used in previous studies, and that their efficiency data may therefore be
more representative of a competition cycling environment.

Figure 1: The gross efficiency of cycling at 60, 80, and 100 rpm at various power outputs are
expressed as a percentage of VO2max Note that gross efficiency at 100 rpm increases as power output
increases so that at 70%, 80% and 90% VO2max the gross efficiencies at the three cadences are not
significantly different. There is no disadvantage to pedaling at high cadences provided that power
outputs are greater than 70% of an individual's maximal aerobic power.(Adapted from Sidossis et al
Int I Sports Med,. 13(5), 407-41], 1992 .)

Figure 2: Delta efficiency during cycling at 60, 80, and 100 rpm. Delta efficiency, (i.e., the ratio
o f the change in the work accomplished to the change in the energy expended), increases
significantly for each increase in cadence so that it is highest at 100 rpm. These data suggest that
muscular efficiency, as reflected by delta efficiency, may be enhanced at higher cadences. (Adapted
from Sidossis et aL rnt J Sports Med, 13(5), 407-411,1992.)

An alternative to efficiency measures is to assess the economy of cycling at different cadences, and
determine if it costs less in terms of oxygen consumption to ride at a given power output while
spinning faster. The most economical cadence is the one that results in the lowest oxygen
consumption. Indeed, one could argue that the externally measured efficiency values provide
interesting theoretical data, but measures of economy have more relevance to performance. Studies
using inexperienced or recreational cyclists, however, show that the most economical cadence falls
between 50 to 60 rpm, and consistently demonstrate that pedaling at 90 to 100 rpm causes an increase
in oxygen consumption in these subjects.

As alluded to by Faria et al (1982), a potential problem in understanding the influence of cadence
on efficiency (and we might extend this to include economy) is that earlier laboratory studies did
not focus on elite level cyclists pedaling at high power outputs. It has been suggested that
experienced cyclists respond differently when compared to untrained or recreational cyclists, such
that they are more economical or efficient at higher rpms. A key study addressing this lack of
applicability of previous research was published by Hagberg et al (1981), who used experienced
cyclists riding their own bicycles on a motordriven treadmill at 20 mph, up a slight grade. The
subjects rode at their preferred cadence and at two cadences above and two below the preferred
frequency. For the group the average preferred cadence was 91 rpm. The authors stated that oxygen
consumption, blood lactate, and ventilation data were minimized at or near the preferred cadence
and, therefore, minimizing these physiological variables was linked to preferred cadence selection.
However, closer examination of their data (i.e., examining the quadratic equation that described the
relationship between oxygen consumption and cadence), reveals that the lowest oxygen consumption
occurred at approximately 70 rpm. Although this is slightly higher than the 50 to 60 rpm values
commonly reported for inexperienced or recreational cyclists, it is still well below the preferred
cadence for this group, and therefore does not support the position that minimizing oxygen
consumption is critical in cadence selection. Therefore, even elite level cyclists, with many years
of training and experience, do not appear to have adapted their physiology so that pedaling at their
preferred cadences leads to a minimization in oxygen consumption.

A recent study conducted at Arizona State University provides additional support for this idea. This
study measured the preferred cadences and most economical cadences of eight experienced cyclists
cycling on their own bicycles on a cycling simulator (Velodyne trainer) at a power output of 200 W
(Marsh and Martin, 1993). The preferred cadence for this group was 85 rpm, close to that reported by
Hagberg et al (1981). The most economical cadence of 56 rpm fell in the middle of the range
previously reported for inexperienced or recreational cyclists. This study clearly demonstrated that
the preferred cadences of experienced cyclists were considerably higher than those at which oxygen
consumption was minimized.

The issue of cycling experience is often raised as a potential explanation of observed differences
in preferred cadence between cyclists and noncyclists (Coast and Welch, 1985; Faria et al, 1982;
Hagberg et al, 1981). Data collected at Arizona State University suggest this may not be the case
(Marsh and Martin, 1993). In the ASU study, experienced runners with no cycling experience, but of
equal aerobic capacity to the cyclists, were asked to pedal at their freely selected cadence at a
constant power output of 200 W. Surprisingly, their average preferred cadence was 92 rpm and their
most economical cadence was approximately 63 rpm, essentially the same as the cadences recorded for
the experienced cyclists (Figure 3). These data challenge the commonly held notion that many years
of cycling experience are required to feel comfortable at high cadences. The data also suggest, some
underlying similarities exist between the cyclists and runners perhaps due to their high fitness
levels, or the aerobic training leading to the high fitness levels.

Figure 3: Steady-state oxygen consumption in cyclists and trained noncyclists during cycling at 50,
65 , 80, 95, and 110 rpm at a power output of 200 VV Note that the cadence at which VO2 is minimized
is significantly lower than the preferred cadence in each group. Despite many years of cycling
experience, the cyclists had not adapted so that they minimized oxygen consumption at their
preferred cadence. Also the preferred cadences of the trained noncyclists were the same as the
cyclists. Therefore many year s of cycling training are not necessarily required to feel comfortable
at high cadences. (Adapted from Marsh and Martin, Med. Sci. Sports Exerc.,
25(11), 1269-127A 1993.)

It could be argued that though running is a weight-bearing activity (as opposed to cycling, which is
weight supported), it shares some commonalities with cycling; that is, it is cyclical, repetitive,
and involves essentially the same muscles producing relatively small forces over extended periods of
time. This could be another explanation for the similarities of these two groups. However, a study
in our laboratory that extends the 1993 work by including untrained noncyclists to assess the
influence of fitness indicates that fitness or training leading to aerobic fitness does play a role
in cadence selection (Marsh and Martin, submitted for publication). We found that the untrained
noncyclists preferred significantly lower cadences compared to cyclists and trained noncyclists.
Also, untrained noncyclists decreased their preferred cadence as power output increased, while the
preferred cadences of cyclists and trained noncyclists remained essentially unchanged as power
output increased. This result, in part, corroborates the notion that noncyclists prefer lower
cadences to cyclists, but it also suggests the influence of fitness or aerobic training in cadence
selection. In summary, cycling experience, per se, is not a prerequisite to selecting a high
preferred cadence, and there is reason to suspect that cadence selection is controlled by
fundamental underlying mechanisms common to all people.

One factor that transcends the cycling experience issue is how we perceive the difficulty of a task.
It has been suggested that an individual's perception of effort is an important factor when
selecting a pedaling rate, and peripheral cues from the active muscles may therefore be given more
consideration than economy or efficiency when selecting a preferred cadence. Ekblom and Goldbarg
(1971) stated that "muscle strain" may provide feedback to the central nervous system, which
strongly influences perceived exertion. In simple terms the hypothesis would be that the feelings we
perceive in the legs during cycling lead us to select a pedaling rate so that we minimize the
perceived effort of the task, even if we are using more oxygen. Typically a rating scale with values
that range from very light effort up to maximal exertion is used to quantify an individual's
perceived exertion (Borg, 1975). Using this technique, several studies have recorded perceived
exertion at different cadences and constant power output, although it should be noted they were not
interested specifically in how perceived exertion might influence cadence selection. Lollgen et al
(1975) manipulated cadence from 40 to 100 rpm at power outputs of 50, 100, 150, and 200 W and found
perceived exertion in trained and untrained subjects decreased with increases in cadence such that
it was minimized at approximately 80 to 100 rpm.

While it is appealing to conclude perceived exertion is therefore an important factor in preferred
cadence selection, other studies have shown that perceived exertion is not always minimized at these
cadences. Stamford and Noble (1974) had high-fit subjects pedal at 40, 60, and 80 rpm at a power
output of 160 W. They reported a parabolic relationship between perceived exertion and cadence,
which was minimized at 60 rpm. Lollgen et al
(26) also reported a quadratic relationship between perceived exertion and cadence, which was
minimized at 65 and 73 rpm during cycling at 70% and 100% of &emdash;2max (Figure 4).

Figure 4: Rating of perceived exernon (RPE) at 40, 60, 80, and 100 rpm during unloaded cycling, and
at intensities corresponding to 70% and 100% of maximal aerobic power. Note that the absolute
changes in the RPE scores are quite small at all three power outputs. However, there is a trend for
perceived exertion to be minimized at higher cadences as power output increases, i.e., RPE minimized
at 60 rpm at 70% VO2max and 80 rpm at 100% VO2max (Adapted from Loligen et aI Med Sci. Sports
Exerc., 12(5), 345-351,1980.)

Recent unpublished data from a study conducted at Arizona State University suggest perceived
exertion is minimized at cadences significantly lower than the preferred cadence at any given power
output, but at cadences slightly higher than those that minimize oxygen consumption. These data are
consistent with Coast et al (1986) who also found cadences that minimize perceived exertion tend to
be slightly higher than those minimizing oxygen consumption. Cadences minimizing perceived exertion,
however, are still significantly lower than the preferred cadences of cyclists. The data from the
ASU study also showed that perceived exertion remained relatively unchanged between 65 and 95 rpm,
but tended to increase at the extremes of the cadence range (50 and 110 rpm). Therefore, cadences in
the middle of the range tested appeared to result in acceptable levels of effort for well-trained,
experienced cyclists and well-trained noncyclists, whereas cadences at the extremes of the range
would likely be avoided.

Now let us take a brief look at the biomechanics of pedaling and examine the forces applied to the
pedals during cycling. Several studies have used force sensing devices mounted in the pedal to
examine the pedal forces as cadence or power output is changed (Cavanagh and Sanderson, 1986; Davis
and Hull, 1981; Hull and Jorge, 1985; LaFortune and Cavanagh, 1980; McLean and LaFortune, 1991;
Patterson and Moreno, 1990). Several of these studies have shown that as cadence increases at
constant power output, the peak force on the pedals decline. In a study of 11 recreational cyclists,
Patterson and Moreno (1990) reported the resultant pedal force averaged across a complete crank
cycle was minimized at 90 and 100 rpm at 100 and 200 W, respectively. Interestingly the preferred
cadences of their subjects at 100 and 200 W were 94 and 98 rpm, respectively. It has been suggested
that if the muscles produce smaller forces more often (as occurs when cadence is increased at
constant speed), they are less likely to fatigue. The rationale for this will become apparent in the
following paragraphs.

Optimal cadence has also been addressed from a biomechanical perspective. Hull and several co-
workers have determined optimal cadences based on biomechanical variables (net joint moments and
muscle stresses) rather than the more commonly used physiological variables such as efficiency or
economy. These two biomechanical variables were selected with good reason. Under conditions where
cocontraction of agonist and antagonist muscle groups is minimal (e.g., quadriceps and hamstrings),
the net joint moment gives an indication of the muscle effort required for the task, and previous
research suggests that minimizing muscle stress is important during submaximal locomotion
(Crowninshield and Brand, 1981). Using experimental data and computer models of the lower extremity,
Redfield and Hull (1986) found a cadence within the range of 95 to 105 rpm minimized the sum of the
average absolute hip and knee moments during 200 W cycling. In follow-up work, Hull et al (1988)
used a more sophisticated computer model to assess the influence of cadence on the muscle stresses
of 12 lower extremity muscles. The optimal cadence, defined as that which minimized the sum of the
12 muscle stresses, was found to be 95 to 100 rpm (Figure 5). The importance of these studies was
the observation that these two biomechanical variables showed close agreement with the cadences
preferred by experienced cyclists. The conclusion from these studies is that minimizing net joint
moments or muscle stresses, both of which are said to give insight into the level of muscle effort
required for the task, may be important in preferred cadence selection. There are, however, some
questions about the validity of the models used in these studies, and more generally, there are
always concerns about the applicability of the model data to real-world conditions. Nevertheless,
these studies show the best agreement between the preferred cadences of experienced cyclists and two
variables that are minimized (i.e., optimized) during cycling.

Figure 5: Data from a computer modeling study that used a muscle stress-based objective function to
determine the optimal cadence at 200 W. The sum of the muscle stresses of 12 lower extremity muscles
was calculated as cadence was varied from 60 to 140 rpm. The model results clearly show that the
optimal cadence (i.e., the cadence that minimized the objective function) was 95-100 rpm. This
agrees very well with the preferred cadences of experienced cyclists and suggests the possibility
that a mechanical variable may be important in preferred cadence selection. (Adapted from Hull et al
Int I Sports Biomech., 4 , 7020, 1988. )

Another approach we can use to attempt to determine why experienced cyclists select high rpms is to
combine the results of these biomechanical and physiological studies and include some information
about the muscle fiber types used during cycling at different cadences. Briefly, our muscles consist
of many thousands of muscle fibers, some of which are characterized as slowtwitch fibers, others
characterized as fast-twitch fibers, and some that have characteristics that fall between these two
extremes. The slow-twitch fibers possess an aerobic endurance quality, while the fast-twitch fibers
are more powerful but fatigue faster. The intermediate fibers possess an ability to develop more
power than the slowtwitch fibers, but do not fatigue as quickly as the fast-twitch fibers. A single
nerve fiber running to one of the large muscles in the leg may control 500 to 1000 of these fibers,
all of which will be either slow, fast, or intermediate. All of these fibers and the single nerve
fiber controlling them are called a motor unit; the muscle fibers of the unit are activated by the
same motor unit action potential and therefore contract in unison.

Fortunately, our bodies automatically select motor units to produce force based on the demands of
the task. For tasks requiring low forces (e.g., standing, walking, recreational cycling at 5 to 10
mph on level ground), slow-twitch motor units are predominantly selected.

As the force requirements of the task increase (e.g., running, a 40-mph sprint finish at the end of
a road race, powering up at steep hill on a mountain bike), fast-twitch units are selected in
addition to the slow units already selected. Remember that laboratory studies have shown a decline
in peak pedal forces as cadence increases at constant power output. According to the widely accepted
motor unit recruitment principles outlined above, fewer fast-twitch fibers should be recruited at a
high cadence compared to a low cadence. Is this what happens in cycling?

Previous studies have alluded to the influence of cadence on motor unit recruitment. Some authors
have speculated that fast-twitch fibers are selectively recruited at higher cadences (e.g., Gaesser
and Brooks, 1975). Often isolated muscle studies, which suggest that slow-twitch muscle fibers may
not be able to contract and relax fast enough at high cadences to be responsible for any useful
power output, are used to argue that selective recruitment of fast twitch fibers occurs at high
cadences, despite the reduction in force per pedal cycle. The nearest direct measurement of fiber
recruitment available to us are studies that assess glycogen depletion in muscle fibers by
extracting a small sample of muscle tissue and assessing the glycogen content pre- and postexercise.
With some limitations, this technique gives an indirect indication of whether slow or fast muscle
fibers are selected during cycling at different cadences; those fibers that are not selected retain
their glycogen stores. Early work by Gollnick et al (1974) concluded that variations in cadence had
no effect on fiber recruitment patterns during cycling. However, these authors were primarily
interested in the influence of power output and exercise duration, rather than cadence. Further,
their methods of evaluating glycogen content were qualitative and later shown to be inadequate for
quantifying small changes in glycogen content (Vollestad et al, 1984).

A recent study by Ahlquist et al (1992), which measured glycogen depletion using a quantitative
technique, produced results consistent with the notion that muscle fibers are recruited based on the
force demands of the task. They assessed glycogen depletion in slow- and fast-twitch muscle fibers
of subjects cycling at 50 and 100 rpm at 85% of their maximal aerobic capacity. The results showed
that at 50 and 100 rpm, a similar number of slow-twitch fibers were recruited. However, fewer
fasttwitch fibers were recruited when the cadence was increased to 100 rpm. This was attributed to
the increased muscle force required per pedal revolution at the lower cadence. This study provides
evidence that the force demands of a task, rather than the velocity of contraction, determines the
type of muscle fibers recruited, and the selection of a preferred cadence during cycling is perhaps
linked to muscle fiber recruitment strategies. It does not appear to support the notion that
cadences of 100 rpm are too high for slow-twitch muscle fibers to operate effectively and contribute
to power output during cycling.

How then does the selection of fewer fast-twitch fibers effect the cyclist, and might this be the
elusive answer as to why cyclists select high rpms during submaximal cycling? Slow-twitch fibers
derive most of the energy necessary for muscular action via oxidative metabolism, in which glucose
and fat are broken down and, in the presence of oxygen, large amounts of ATP are formed. ATP, or
adenosine triphosphate, is the immediate source of energy for muscle action. In contrast, fast-
twitch fibers break down more glucose than can be oxidized to carbon dioxide, which results in the
production of lactic acid. While lactic acid can actually be reutilized as an energy source, in
large quantities it has been linked to a decrease in muscle force production (see Metzger, 1992, for
a thorough review of factors affecting muscle force production).

At any submaximal cycling speed, if we select a high cadence, the glycogen depletion study of
Ahlquist et al (1992) suggests that we will minimize the recruitment of fast-twitch fibers. However,
we can still supply ATP to the working muscles of the leg using predominantly slow-twitch or
intermediate fibers. Since there is less reliance on fasttwitch fibers, there is less likelihood of
a large increase in lactic acid in the working muscle. This theory fits nicely with the observation
that fatigue seems to be delayed when using a high cadence, compared to a low cadence. In addition,
individual differences in percentage of slow- and fast-twitch fibers may help to explain why some
individuals prefer different cadences and why some of us excel at short sprints, while others
perform better during long, sustained efforts. Recreational cyclists, who cycle slowly so that force
demands are low, have no need to pedal at high cadences since they are already utilizing their slow-
twitch fibers. They may even be pedaling at their most economical cadence, since they are in no
hurry to get from A to
B.

In summary, laboratory studies indicate that experienced cyclists do not use their most economical
or efficient cadences. However, cadences of 90 to 100 rpm are probably beneficial in spite of
decreases in economy and efficiency. The explanation proposed here suggests the use of high rpms
results in a decrease in average pedal force per revolution and leads to the recruitment of fewer
fast-twitch fibers, placing the reliance for muscle power development primarily on the slow-twitch
and intermediate fibers. The advantage to the cyclist is there is less likelihood of a rapid
accumulation of lactic acid, with the resulting decrease in muscle force production. More
interdisciplinary studies in cycling, particularly those that combine biomechanical and
physiological data, are needed to confirm or refute this theory.

It seems likely that physiological, psychological, and biomechanical factors all play a role in
preferred cadence selection, albeit to a varying degree, depending on the goals of the task. For
example, maximal sprinting tasks have not been considered in this article, and it is likely that the
criteria for sprint cadence selection are different than for submaximal cycling tasks. As we have
seen, one of the difficulties in attempting to provide a definitive answer to the question of what
are the determinants of the preferred cadence is the inconsistent nature of some of the scientific
literature. Also, this article works from the supposition that for a submaximal task, the human body
will attempt to minimize those variables important to preferred cadence selection. The author is
certainly not alone in this view, but acknowledges this logic may be flawed, and, in fact, the body
may be trying to maximize some as yet undetermined variable, such as muscle power output (see
Sargeant, 1994).

REFERENCES

1) Ahlquist, L. E., Bassett, D. R, Sufit, R., Nagle, F. J., and Thomas, D.
P. (1992). The effect of pedaling frequency on glycogen depletion rates in type I and type II
quadriceps muscle fibers during submaximal cycling exercise. Eur. J. Appl. Physiol.
65: 360-364.

2) Benedict, F. G. and Cathcart, E. P. (1913). Muscular Work. Publication No. 187, Washington, DC:
Carnegie Institute.

3) Borg, G. (1970). Perceived exertion as an indicator of somatic stress. Scand. J. Rehab.
Med. 2: 92-98.

4) Cavanagh, P. R. and Sanderson, D. J. (1986). The biomechanics of cycling: studies of the
pedaling mechanics of elite pursuit riders. Science of Cycling. Human Kinetics Publishers,
Champaign IL.

5) Coast, J. R., Cox, R. H., and Welch, H. G. (1986). Optimal pedalling rate in prolonged bouts of
cycle ergometry. Med. Sci. Sports Exerc. 18: 225-230.

6) Coast, J. R. and Welch, H. G. ( 1985). Linear increase in optimal pedal rate with increased
power output in cycle ergometry. Eur. J. Appl. Physiol.
7: 339342.

8) Crowninshield, R. D. and Brand, R. A. (1981). A physiologically based criterion of muscle force
prediction in locomotion. J. Biomech. 14: 793-801.

9) Davis, R. R. and Hull, M. L. (1981). Measurement of pedal loading in bicyding-II. Analysis and
results. J. Biomech. 14: 857-872.

10) Dickinson, S. (1929). The effciency of bicycle pedalling as affected by speed and load. J.
Physiol. 67: 242-255.

11)Ekblom, B. and Goldbarg, A. N. (1971). The influence of physical training and other factors on
the subjective rating of perceived exertion. Acta Physiol. Scand. 83: 399-406.

12) Faria, I., Sjojaard, G., and BondePetersen, F. (1982). Oxygen cost during different pedalling
speeds for constant power output J. Sports Med.22: 295-299.

13) Gaesser, G. A. and Brooks, G. A. (1975). Muscular efficiency during steady-rate exercise:
effects of speed and work. J. Appl. Physiol. 38: 1132- 1139.

14) Garry, R. C. and Wishart, G. M. (1931). On the existence of a most effficient speed in bicycle
pedalling and the problem of determining human muscular effficiency. J. Physiol. 72: 425-437.

15) Gollnick, P. D., Piehl, K., and Saltin, B. (1974). Selective glycogen depletion pattern in human
muscle fibers after exercise of varying intensity and at varying pedalling rates. J.
Physiol.241: 45-57.

16) Hagberg, J. M., Mullin, J. P., Giese, M. D., and Spitznagel, E. (1981). Effect of pedaling rate
on submaximal exercise responses of competitive cyclists. J. Appl. Physiol. 51: 447-451.

17) Hull, M. L. and Jorge, M. (1985). A method for biomechanical analysis of bicycle pedalling. J.
Biomech.18: 307-316.

18) Hull, M. L., Gonzalez, H., and Redfield, R. (1988). Optimization of pedaling rate in cycling
using a muscle stress-based objective function. Int. J. Sport Biomech. 4, 1-21.

19) LaFortune, M. A. and Cavanagh, P. R. (1980). Force effectiveness during cycling. Med. Sci.
Sports Exerc. 12: 95.

20) Lollgen, H., Graham, T., and Sj0gaard, G. (1980). Musde metabolites, force and perceived
exertion bicycling at varying rates. Med. Sci. Sports Exerc. 12: 345-351.

21) Lollgen, H., Ulmer, H. V., Gross, R., Wilbert, G., and Nieding, G. V.
(22). Methodological aspects of perceived exertion rating and its relation to pedaling rate and
rotating mass. Eur. J. Appl. Physiol. 34: 205-215.

23) McLean, B. D. and LaFortune, M. A. (1991). Influence of cadence on mechanical parameters of
pedalling. In Proceedings of the 13th International Congress of Biomechanics. University of
Western Australia, Perth, Australia.

24) Marsh, A. P. and Martin, P. E. (1993). The association between cycling experience and preferred
and most economical cycling cadences. Med. Sci. Sports Exerc. 25: 1269-1274.

25) Metzger, J. M. (1992). Mechanism of chemomechanical coupling in skeletal muscle during work.
Perspectives in exercise science and sports medicine. Volume 5: Energy metabolism in exercise
and sport (D. R. Lamb, Ed.) pp. 1-51, Wm. C. Brown.

26) Patterson, R. P. and Moreno, M. I. (1990). Bicyde pedalling forces as a function of pedalling
rate and power output. Med. Sci. Sports Exerc. 22: 512516.

27) Redfield, R. and Hull, M. L. (1986). On the relation between joint moments and pedalling rates
at constant power in bicycling. J. Biomech. 19: 317-329.

28) Sargeant, A. J. (1994). Human power output and muscle fatigue. Int. J. Sports Med. 15: 116-121.

29) Seabury, J. J., Adams, W. C., and Ramey, M. R. (1977). Influence of pedaling rate and power
output on energy expenditure during bicycle ergometry. Ergonomics. 20:491-498.

30) Sidossis, L. S., Horowitz, J. F., and Coyle, E. F. (1992). Load and velocity of contraction
influence gross and delta mechanical efficiency. Int. J. Sports Med. 13: 407-411.

31) Stamford, B. A. and Noble, B. J. (1974). Metabolic cost and perception of effort during bicycle
ergometer work performance. Med. Sci. Sports.6: 226-231.

32) Suzuki, Y. (1979). Mechanical efficiency of fast- and slow-twitch muscle fibers in man during
cycling. J. Appl. Physiol. 47: 263-267.

33)Vollestad, N. K., Vaage, O., and Hermansen, L. (1984). Musde glycogen depletion patterns in type
I and type II fibers during prolonged severe exercise in man. Acta Physiol. Scand.122: 433-441.

Anthony P. Marsh, Ph.D. Department of Health and Physical Education California State University,
Sacramento, CA 95819-6073

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Taken from : Cycling Science - Summer 1996 - What Determines The Optimal Cadence?

See also Cycling Science - Spring 1996 - Editors Mailbox.

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M

M. W. Smith

Guest
On 10 Feb 2004 19:05:55 GMT, Larry Weisenthal <[email protected]> wrote:

> Interesting speculations.
>
> Some data first.
>
> Swimmers burn negligible fat. Costill compared swimmers, runners, and cyclists. Each swam, ran, or
> cycled at 70% VO2 max (just sub-lactate threshold) for 40 minutes. Swimmers emerged borderline
> hypoglycemic, with negligible products of fat metabolism circulating in their bloodstream.
> Cyclists and runners had significantly higher blood sugar and had copious products of fat
> metabolism circulating in their bloodstream. Costill repeated the experiment, with triathletes
> doing each of the disciplines. Same result.

Does this mean that swimming is not good for losing weight? I suppose it means that the Atkins diet
will work better for bikers, runners, and weight lifters than for swimmers.

Or, what happens when a swimmer goes on the Atkins diet? He swims a workout and burns his glycogen,
emerging borderline hypoclycemic, and then he does not eat any carbs. On the face of it, he would
not be able to complete a workout the next day, or, he would swim that workout at a severely
degraded level. But that isn't what happens. When I am on the induction phase of Atkins, where I am
eating very little carbohydrate of any kind, my swimming is adversely affected, but I can still swim
a hard workout. So either the body must be able to replenish the glycogen from stored fat and
protein, or a swimmer can shift his energy cycle to the same one other athletes use just by not
eating carbs.

martin

--
If you are a US citizen, please use your constitutional right to vote, because we badly need a new
president.
 
M

MJuric

Guest
On Wed, 11 Feb 2004 11:52:28 +0100, "m. w. smith"
<[email protected]> wrote:

>On 10 Feb 2004 19:05:55 GMT, Larry Weisenthal <[email protected]> wrote:
>
>> Interesting speculations.
>>
>> Some data first.
>>
>> Swimmers burn negligible fat. Costill compared swimmers, runners, and cyclists. Each swam, ran,
>> or cycled at 70% VO2 max (just sub-lactate threshold) for 40 minutes. Swimmers emerged borderline
>> hypoglycemic, with negligible products of fat metabolism circulating in their bloodstream.
>> Cyclists and runners had significantly higher blood sugar and had copious products of fat
>> metabolism circulating in their bloodstream. Costill repeated the experiment, with triathletes
>> doing each of the disciplines. Same result.
>
>Does this mean that swimming is not good for losing weight? I suppose it means that the Atkins diet
>will work better for bikers, runners, and weight lifters than for swimmers.
>
>Or, what happens when a swimmer goes on the Atkins diet? He swims a workout and burns his glycogen,
>emerging borderline hypoclycemic, and then he does not eat any carbs. On the face of it, he would
>not be able to complete a workout the next day, or, he would swim that workout at a severely
>degraded level.

My understanding is that fat cannot be directly converted to glucose, however protein can. I
suspect, don't know, that a swimmer on Atkins would lose weight simply because losing weight
has less to do with what you eat as how much of it you eat. I also suspect, don't know, that
the swimmer that does not replinish there glycogen stores will in fact suffer in the area of
performance. Of course this will be highly variable from person to person as well as
effected by intensity and duration of the workout. Everyone uses a combination of glucose
and fat as energy. The percent use of fat GENERALLY goes up as intensity goes down. The
percent use of fat, in the abcense of or low levels of glucose GENERALLY goes up. However it
is my understanding that the metabolisation of fat is dependant on gluccose, IOW if glucose
is very low teh body will switch to burning protein not fat. Of course this is fine for
short periods of time as seme protein is available for burning, however, again my
understanding, no real system is available for the storage of protein otehr than lean muscle
mass so for longer period of excercise in which you end up burning protein it will come from
muscle, not a good thing. You can "train" your body to burn fat more effeciently, however
you do not have to be in a satte of glycogen depletion in order to accomplish this. Simply
lower the intensity and increasing teh duration fo a workout has a similar, probably not
excatly the same, but similar effect. IMO, particulalary if the post from Larry is true,
that swimming burns more glycogen percentile than does leg activies, it makes little or no
sense to me to live and or workout in a glycogen depleted state. Without question certain
organs and nervous system functions operate ONLY on glucose. So the body has certain safe
guards to protect those organs. It just doesn't make sense to me to risk activating those
safe guards searching for benefits that can gained in much safer methods. Of course this as
usual is merely my opinion.

> But that isn't what happens. When I am on the induction phase of Atkins, where I am eating very
> little carbohydrate of any kind, my swimming is adversely affected, but I can still swim a hard
> workout. So either the body must be able to replenish the glycogen from stored fat and protein, or
> a swimmer can shift his energy cycle to the same one other athletes use just by not eating carbs.

The body not only can but must create glycogen in the abscence of eating them. As stated
above certain organs and nervous system operates on Glycogen only. However the body cannot
create them as fast as tehy can be eaten. And the systems your depending on when working out
in a glycogen depleted state are no diffenret than any other athlete. However by not having
glycogen availabale you have eliminate done system being available to you. Probably not good
for performance. As we are all an experimant of one you may be an individual that does well
under lwo glycogen availability. However I suspect that a person could certainly find
workouts that you could not do as well in a glycogen depleted states.

~Matt

>
>martin
>
>--
>If you are a US citizen, please use your constitutional right to vote, because we badly need a new
>president.
 
A

Andres Muro

Guest
From what I understand, protein cannot be turned into glucose. fat can, but at a very slow rate. So,
if you are swimming very slowly, you can continue to do so and turn fat into glucose. For more
intense excersise, you need to have glycogen directly accessible. So, once you consume your
available source of glycogen, you need to keep on replenishing it.

For loosing weight, Atkins makes sense as long as you don't burn glycogen faster than you replenish
it. As you increase the intensity of excersise, you need to make glycogen readily available for you
muscles and you need to take in some.

Because it is easier to break down glucose for energy, your body will use it as long as it is
available, and store what is not consumed as fat. If you deprive your body of carbs, your body will
be force to turn fat into carbs for energy. The metabolic process to do this requires more energy
than just burning carbs, and you force your body to break down stored fat. Also, in order to break
down and flush protein through the kidneys you have some additional caloric expenditure.

So, in essence, by depriving your body from carbs, you are forcing your body to break down fat and
because the metabolic process to break down fat and to break down protein is more labor intesnive,
you are supossed to get the extra milage from forcing your body into higher metabolic activity.

As far as I know, protein is used to build muscle and to facilitate metabolic function. However, it
is not fuel.

This of course is as far as I know and in my humble opinion. It is not scientific at all.

Regarding swimming for loosing weight, it is great excercise. Because swimming is highly aerobic
activity, people can swim for a long time and burn a lot of calories. However, because swimming is
not weight bareing excercise, it doesn't have the extra labor of holding your body up and supporting
it. Sports that require that you do this, will of course burn more calories for equal efforts. So,
comparatively speaking, runners will burn more calories, then cyclists, then swimmers. Also, because
cycling and running use your leg muscles, and probably larger amounts of muscle tissue, they may
require more energy. So, swimming is great, but it is possilbe that running and cycling may burn
more calories and may be slightly more effective to loose fat.

There is a theory that swimming is not a good way to lose weight because fat floats, and the body
will store some for this purpose. However, I don't buy that theory. Burning fat is a mathematical
equation. You burn calories to get energy. If you are eating less calories than what you are
butning, your body will keep burning fat until you equalize the exchange. Your body will not stop
burning fat to help you float.

Ultimately, loodsing weight has to do with how many calories you burn and how many you eat. I can
swim 10,000 yards and burn 3500 calories. I can go out right after and down a large pepperoni pizza,
six Sam Adams, bread sticks and potato chips. Later, I may drin a 2 liter coke and a bag of oreos. I
will certainly not lose weight swimming, running or cycling if I do that. I love to eat. I ride,
run, and swim. I still have some body fat. However, it is not because I swim instead of running all
day. It is because I am eating more than what I am burning.

Andres

MJuric wrote in message news:<[email protected]>...
> On Wed, 11 Feb 2004 11:52:28 +0100, "m. w. smith" <[email protected]> wrote:
>
> >On 10 Feb 2004 19:05:55 GMT, Larry Weisenthal <[email protected]> wrote:
> >
> >> Interesting speculations.
> >>
> >> Some data first.
> >>
> >> Swimmers burn negligible fat. Costill compared swimmers, runners, and cyclists. Each swam, ran,
> >> or cycled at 70% VO2 max (just sub-lactate threshold) for 40 minutes. Swimmers emerged
> >> borderline hypoglycemic, with negligible products of fat metabolism circulating in their
> >> bloodstream. Cyclists and4 runners had significantly higher blood sugar and had copious
> >> products of fat metabolism circulating in their bloodstream. Costill repeated the experiment,
> >> with triathletes doing each of the disciplines. Same result.
> >
> >Does this mean that swimming is not good for losing weight? I suppose it means that the Atkins
> >diet will work better for bikers, runners, and weight lifters than for swimmers.
> >
> >Or, what happens when a swimmer goes on the Atkins diet? He swims a workout and burns his
> >glycogen, emerging borderline hypoclycemic, and then he does not eat any carbs. On the face of
> >it, he would not be able to complete a workout the next day, or, he would swim that workout at a
> >severely degraded level.
>
> My understanding is that fat cannot be directly converted to glucose, however protein can. I
> suspect, don't know, that a swimmer on Atkins would lose weight simply because losing weight
> has less to do with what you eat as how much of it you eat. I also suspect, don't know, that
> the swimmer that does not replinish there glycogen stores will in fact suffer in the area of
> performance. Of course this will be highly variable from person to person as well as
> effected by intensity and duration of the workout. Everyone uses a combination of glucose
> and fat as energy. The percent use of fat GENERALLY goes up as intensity goes down. The
> percent use of fat, in the abcense of or low levels of glucose GENERALLY goes up. However it
> is my understanding that the metabolisation of fat is dependant on gluccose, IOW if glucose
> is very low teh body will switch to burning protein not fat. Of course this is fine for
> short periods of time as seme protein is available for burning, however, again my
> understanding, no real system is available for the storage of protein otehr than lean muscle
> mass so for longer period of excercise in which you end up burning protein it will come from
> muscle, not a good thing. You can "train" your body to burn fat more effeciently, however
> you do not have to be in a satte of glycogen depletion in order to accomplish this. Simply
> lower the intensity and increasing teh duration fo a workout has a similar, probably not
> excatly the same, but similar effect. IMO, particulalary if the post from Larry is true,
> that swimming burns more glycogen percentile than does leg activies, it makes little or no
> sense to me to live and or workout in a glycogen depleted state. Without question certain
> organs and nervous system functions operate ONLY on glucose. So the body has certain safe
> guards to protect those organs. It just doesn't make sense to me to risk activating those
> safe guards searching for benefits that can gained in much safer methods. Of course this as
> usual is merely my opinion.
>
>
> > But that isn't what happens. When I am on the induction phase of Atkins, where I am eating very
> > little carbohydrate of any kind, my swimming is adversely affected, but I can still swim a hard
> > workout. So either the body must be able to replenish the glycogen from stored fat and protein,
> > or a swimmer can shift his energy cycle to the same one other athletes use just by not eating
> > carbs.
>
> The body not only can but must create glycogen in the abscence of eating them. As stated
> above certain organs and nervous system operates on Glycogen only. However the body cannot
> create them as fast as tehy can be eaten. And the systems your depending on when working out
> in a glycogen depleted state are no diffenret than any other athlete. However by not having
> glycogen availabale you have eliminate done system being available to you. Probably not good
> for performance. As we are all an experimant of one you may be an individual that does well
> under lwo glycogen availability. However I suspect that a person could certainly find
> workouts that you could not do as well in a glycogen depleted states.
>
> ~Matt
>
> >
> >martin
> >
> >--
> >If you are a US citizen, please use your constitutional right to vote, because we badly need a
> >new president.
 
M

M. W. Smith

Guest
On 12 Feb 2004 05:42:47 GMT, Larry Weisenthal <[email protected]> wrote:

>>> So either the body must be able to replenish the glycogen from
> stored fat and protein<<
>
> You can make glucose (and therefore glycogen) from protein, but not from fat. The process (protein-
> >glucose) is called gluconeogenesis.

So that means one can't lose weight by swimming without also restricting calorie intake, and
people who use the Atkins diet are better served taking their exercise as biking, running, and
weight training.

martin

--
If you are a US citizen, please use your constitutional right to vote, because we badly need a new
president.
 
M

M. W. Smith

Guest
On Wed, 11 Feb 2004 17:20:34 GMT, <MJuric> wrote:
> I also suspect, don't know, that the swimmer that does not replinish there glycogen stores
> will in fact suffer in the area of performance.

I said that was my experience, but that the difference was negligible for the case of a person who
is trying to lose weight. It is irrelevant for a person who is trying to compete, because he
wouldn't be competing while trying to lose weight.

> Of course this will be highly variable from person to person as well as effected by intensity and
> duration of the workout. Everyone uses a combination of glucose and fat as energy. The percent use
> of fat GENERALLY goes up as intensity goes down. The percent use of fat, in the abcense of or low
> levels of glucose GENERALLY goes up. However it is my understanding that the metabolisation of fat
> is dependant on gluccose, IOW if glucose is very low teh body will switch to burning protein not
> fat. Of course this is fine for short periods of time as seme protein is available for burning,
> however, again my understanding, no real system is available for the storage of protein otehr than
> lean muscle mass so for longer period of excercise in which you end up burning protein it will
> come from muscle, not a good thing.

Well, apparently, in the absence of carbohydrate input, the body goes into ketosis, which means fat
*is* being burned.

> You can "train" your body to burn fat more effeciently, however you do not have to be in a
> satte of glycogen depletion in order to accomplish this. Simply lower the intensity and
> increasing teh duration fo a workout has a similar, probably not excatly the same, but
> similar effect.

That increases the percentage of fat burned, not the amount of fat burned.

> IMO, particulalary if the post from Larry is true, that swimming burns more glycogen
> percentile than does leg activies, it makes little or no sense to me to live and or workout
> in a glycogen depleted state. Without question certain organs and nervous system functions
> operate ONLY on glucose. So the body has certain safe guards to protect those organs. It
> just doesn't make sense to me to risk activating those safe guards searching for benefits
> that can gained in much safer methods. Of course this as usual is merely my opinion.

...except that we humans used to be basically meat eaters before farming. I don't think it is
difficult for the body to make the glucose it needs. Most of the work done by the body during a
caveman day would be non-sprinting, right? so fat burning would work just fine. The safeguards you
are talking about are the normal operating mode for the body most of the time. You might sprint
through your day, but I don't.

>> But that isn't what happens. When I am on the induction phase of Atkins, where I am eating
>> very little carbohydrate of any kind, my swimming is adversely affected, but I can still swim
>> a hard workout. So either the body must be able to replenish the glycogen from stored fat and
>> protein, or a swimmer can shift his energy cycle to the same one other athletes use just by
>> not eating carbs.
>
> The body not only can but must create glycogen in the abscence of eating them. As stated
> above certain organs and nervous system operates on Glycogen only. However the body cannot
> create them as fast as tehy can be eaten.

That's a strawman, because the body only has to make them as fast as they are needed. The problem
for overweight people is precisely that they eat them faster than they are needed.

> And the systems your depending on when working out in a glycogen depleted state are no diffenret
> than any other athlete. However by not having glycogen availabale you have eliminate done system
> being available to you. Probably not good for performance.

But we are talking about weight loss, not performance.

> As we are all an experimant of one you may be an individual that does well under lwo
> glycogen availability. However I suspect that a person could certainly find workouts that
> you could not do as well in a glycogen depleted states.

But that's what I said. I said my swimming was adversely affected, but not so as I couldn't swim a
hard workout. I just didn't go as fast.

martin

--
If you are a US citizen, please use your constitutional right to vote, because we badly need a new
president.
 
M

MJuric

Guest
On Thu, 12 Feb 2004 10:44:10 +0100, "m. w. smith"
<[email protected]> wrote:

>On Wed, 11 Feb 2004 17:20:34 GMT, <MJuric> wrote:
>> I also suspect, don't know, that the swimmer that does not replinish there glycogen stores
>> will in fact suffer in the area of performance.
>
>I said that was my experience, but that the difference was negligible for the case of a person who
>is trying to lose weight. It is irrelevant for a person who is trying to compete, because he
>wouldn't be competing while trying to lose weight.

I guess I'm not 100% what the point of the above is. Weight loss is simply a matter of burning more
than you bring in. What you burn 3000 cal of fat or 3000 cal of carbs makes no difference. Your
statement of "It is irrelevant for a person who is trying to compete, because he wouldn't be
competing while trying to lose weight." simply makes no since to me. We are talking about what is a
safe diet, in the sense of everyday eating. If we completely disreguard performance while on that
diet I guess we have no arguement. My point is simply this. Two people who ends up with the same
caloric deficit at the end of the day, in very general terms, will lose the same amount of weight.
What they ate will have, some, but very little bearing on the weight loss. All that is left to
discuss is how these two people will perform. IMO the one operating in a glycogen depleted state
will suffer on the performance end of things on any workouts that cross over into intense 70%+ MHR
and even a bit at lower intensities.

>
>> Of course this will be highly variable from person to person as well as effected by intensity and
>> duration of the workout. Everyone uses a combination of glucose and fat as energy. The percent
>> use of fat GENERALLY goes up as intensity goes down. The percent use of fat, in the abcense of or
>> low levels of glucose GENERALLY goes up. However it is my understanding that the metabolisation
>> of fat is dependant on gluccose, IOW if glucose is very low teh body will switch to burning
>> protein not fat. Of course this is fine for short periods of time as seme protein is available
>> for burning, however, again my understanding, no real system is available for the storage of
>> protein otehr than lean muscle mass so for longer period of excercise in which you end up burning
>> protein it will come from muscle, not a good thing.
>
>Well, apparently, in the absence of carbohydrate input, the body goes into ketosis, which means fat
>*is* being burned.

Well here's an article on Ketosis. As the author said, I'll let you decide.

http://www.cyberiron.com/nutrition/ketosis.html

I'm sure there is any number of arguments that one could make the the body does "X" under
"Y" circumstances. I suspect that most of these fairly extreme cases are not meant to be
"normal body operating procedure". As mentioned earlier as the effort goes up so does
glycogen consumption. I suspect that doing a hard workout 80-85% MHR whilst in a complete
state of ketosis would prove to be difficult.

>
>> You can "train" your body to burn fat more effeciently, however you do not have to be in a
>> satte of glycogen depletion in order to accomplish this. Simply lower the intensity and
>> increasing teh duration fo a workout has a similar, probably not excatly the same, but
>> similar effect.
>
>That increases the percentage of fat burned, not the amount of fat burned.

If you want to increase the amount burnt simply workout longer. Low intensity for a
long time.

>> IMO, particulalary if the post from Larry is true, that swimming burns more glycogen
>> percentile than does leg activies, it makes little or no sense to me to live and or workout
>> in a glycogen depleted state. Without question certain organs and nervous system functions
>> operate ONLY on glucose. So the body has certain safe guards to protect those organs. It
>> just doesn't make sense to me to risk activating those safe guards searching for benefits
>> that can gained in much safer methods. Of course this as usual is merely my opinion.
>
>...except that we humans used to be basically meat eaters before farming.

In your opinion. Some scientist believe we were not meat eaters as meat was a scarce resource and
difficult to come by. My opinion is that we have always been omnivores...scavengers if you will.
Eating anything that was available. Rotting meat, berrys, roots etc.

>I don't think it is difficult for the body to make the glucose it needs. Most of the work done by
>the body during a caveman day would be non-sprinting, right? so fat burning would work just fine.

Depends. I suspect that we probably did alot of intermitant sprinting. Either away from preditors or
later on after preditors while hunting. Also without doubt a great deal of our activities were at a
much higher HR than what we do today. Climbing trees, mountains etc. Whether this was at 70%MHR + I
don't know but to say we never burned glycogen is a bit of stretch. Not to mention that the brain
and some organs burn ONLY glycogen. Also mister caveman was much more active than I probably
spending many hours just gather food, not a 15 minute drive by at the local grocer. All in all I
think glycogen depletion was a great problem for mister cave man as even slow movement burns a
certain percentage of glycogen.

>The safeguards you are talking about are the normal operating mode for the body most of the time.
>You might sprint through your day, but I don't.

Sprinting is not the only means or need for Glycogen. Gylcogen is burnt constantly. However mister
caveman woudl be lion lunch if he HAD to sprint and didn't have any. The option to not performing
well was death...not just simply slower lap times.

>
>>> But that isn't what happens. When I am on the induction phase of Atkins, where I am eating very
>>> little carbohydrate of any kind, my swimming is adversely affected, but I can still swim a hard
>>> workout. So either the body must be able to replenish the glycogen from stored fat and protein,
>>> or a swimmer can shift his energy cycle to the same one other athletes use just by not eating
>>> carbs.
>>
>> The body not only can but must create glycogen in the abscence of eating them. As stated
>> above certain organs and nervous system operates on Glycogen only. However the body cannot
>> create them as fast as tehy can be eaten.
>
>That's a strawman, because the body only has to make them as fast as they are needed.

Of course I agree. However this does not mean that the need cannot be greater than teh bodies
ability to create glycogen. The body cannot create them fast enough to provide a complete muscle
glycogen replishment before the next workout assuming a faily high level of gylocogen depletion. So
over a period of a couple of days the muscle glycogen is depleted and performance suffers. Of course
back to the idea that we are not talking about working out then we have no argument.

>The problem for overweight people is precisely that they eat them faster than they are needed.

No the problem is THEY EAT TO MUCH. Not carbs not fat not protein. They eat to many calories PERIOD.

>
>> And the systems your depending on when working out in a glycogen depleted state are no diffenret
>> than any other athlete. However by not having glycogen availabale you have eliminate done system
>> being available to you. Probably not good for performance.
>
>But we are talking about weight loss, not performance.

I'm talking about diet. Diet as in what one should eat all of the time to lose weight, to maintain
weight, to live. I frankly workout and need to perform while I'm working out. If I'm trying to lose
weight I still need to perform. I'm quite surprised that in a swimming forum you would think the two
are exclusive.

>
>> As we are all an experimant of one you may be an individual that does well under lwo
>> glycogen availability. However I suspect that a person could certainly find workouts that
>> you could not do as well in a glycogen depleted states.
>
>But that's what I said. I said my swimming was adversely affected, but not so as I couldn't swim a
>hard workout. I just didn't go as fast.

Sorry must have miss read that. Saw "Isn't" instead of is. As stated before I guess I don't see the
point. Why would one accept a lower level of performance rather than eat a diet that produces both
weightloss and performance? If we are disreguarding performance than yes, eat anything just as long
as it's less than what you burn.

~Matt

>
>martin
>
>--
>If you are a US citizen, please use your constitutional right to vote, because we badly need a new
>president.
 
M

MJuric

Guest
On Thu, 12 Feb 2004 17:46:18 GMT, MJuric wrote:

>>> Without question certain organs and nervous system functions operate ONLY on glucose.

Must correct self here.... My bad for using the words like ONLY.. similar to never or any other
absolute negative or positive there are usually exceptions.

Apparently during periods of prolong starvation. Ketones can be reduced to something called ß-
hydroxybutyrate that can be used by the brain for up to 70% of it's energy needs.

~Matt
 
M

MJuric

Guest
On Thu, 12 Feb 2004 17:46:18 GMT, MJuric wrote:

>On Thu, 12 Feb 2004 10:44:10 +0100, "m. w. smith" <[email protected]> wrote:
>

>>
>>Well, apparently, in the absence of carbohydrate input, the body goes into ketosis, which means
>>fat *is* being burned.
>
> Well here's an article on Ketosis. As the author said, I'll let you decide.
>
>http://www.cyberiron.com/nutrition/ketosis.html
>

Another correction and or question. For some reason I was under the impression and have
heard it said either here or over at
R.R. That Glucose was necessary for the metobalisation<SP> of fat. From a couple of things I was
looking at apparently that is not true. It looks like both fat and glucose join the same cycle
but are not in the same cycle. IOW glucose is converted to Pyruvate and fat goes through a
couple of conversions and then to Pyruvate at which point they are both treated the same. Is
there anything that comes from the metabolisation of glucose that is necessary for the fat
metabilisation that cannot be gotten elsewhere?

~Matt
 
M

M. W. Smith

Guest
On Thu, 12 Feb 2004 17:46:18 GMT, <MJuric> wrote:

> On Thu, 12 Feb 2004 10:44:10 +0100, "m. w. smith" <[email protected]> wrote:
>
>> On Wed, 11 Feb 2004 17:20:34 GMT, <MJuric> wrote:
>>> I also suspect, don't know, that the swimmer that does not replinish there glycogen stores
>>> will in fact suffer in the area of performance.
>>
>> I said that was my experience, but that the difference was negligible for the case of a person
>> who is trying to lose weight. It is irrelevant for a person who is trying to compete, because he
>> wouldn't be competing while trying to lose weight.
>
> I guess I'm not 100% what the point of the above is. Weight loss is simply a matter of burning
> more than you bring in.

Well that's it then. The Nobel Prize to you. Weight loss is simply a matter of burning more than you
bring in. What is everybody's problem? Don't they know how simple it is?

You would probably tell a depressed person to "Snap out of it." It's as simple as that. Just snap
out of it. What's the big deal?

My point was that top performance is only important to a swimmer who is competing, so the fact that
a swimmer's sprint times degrade a bit while on a low-carb diet isn't important to that swimmer,
because she has made a choice to lose weight. People who are trying to lose weight (ie because they
are overweight, not because they are trying to "make weight" like a wrestler) are not competing
while they are trying to lose weight. Or they shouldn't be. So the fact that they can't sprint very
well while they are on a low-carb diet to lose weight isn't important.

> What you burn 3000 cal of fat or 3000 cal of carbs makes no difference.

Yes, it does. According to Larry's article, if I spend forty minutes in HIIT as running and biking,
I will burn more fat than if I spend the same forty minutes in HIIT in the pool. In the pool, I will
lose weight due to burning glycogen, which doesn't count as real weight loss. If I do the forty
minutes in the pool, and then I choose not to replenish my glycogen with fruit and pasta and bread,
I will lose real weight as my body converts muscle from protein to glucose. But I don't want to lose
muscle, so if I don't replenish my glycogen with carbs (difficult to resist after a hard swimming
session), then I must eat or have already eaten sufficient protein to prevent my body from
canabalizing my own muscles.

To lose weight, what I want to do is burn fat, so, according to Larry, I should do more running,
biking, and other land-based HIIT than swimming.

> Your statement of "It is irrelevant for a person who is trying to compete, because he wouldn't be
> competing while trying to lose weight." simply makes no since to me. We are talking about what is
> a safe diet, in the sense of everyday eating.

No, we are talking about losing weight. That isn't an everyday diet. The "everyday" Atkins diet is
what most people refer to as a "normal, healthy diet." It isn't a high fat diet. It is a low-refined-
carb diet, ie little or no refined suger, little or no white flour. Otherwise, it is pretty much
what any fit person would eat. During the weight loss phasees of the Atkins diet, the low-carb
aspect is exagerated, so that in the first phase you eat no more than 20g of carbs per day, which
means no sugar, no four, and no carbs at all excpet high fiber carbs like AllBran. That's not a
healthy diet, but you only eat that way while you are trying to lose weight. Losing weight is not a
never-ending story. You actually get to your target weight, and then you change your diet to a
healthy diet.

While I am trying to lose weight, losing weight is what is important to me, not competing. I choose
to lose weight, and in making that choice I recognize that while i am losing weight, I will not be
functioning at 100%, regardless of whose diet I am on, and so competing better not be high on my
priority list. You can't have your cake and eat it too. Pun intended.

> If we completely disreguard performance while on that diet I guess we have no arguement. My point
> is simply this. Two people who ends up with the same caloric deficit at the end of the day, in
> very general terms, will lose the same amount of weight. What they ate will have, some, but very
> little bearing on the weight loss.

From what Larry reported, that doesn't follow.

> All that is left to discuss is how these two people will perform. IMO the one operating in a
> glycogen depleted state will suffer on the performance end of things on any workouts that cross
> over into intense 70%+ MHR and even a bit at lower intensities.

Why are they competing while they are trying to lose weight?

>>> Of course this will be highly variable from person to person as well as effected by intensity
>>> and duration of the workout. Everyone uses a combination of glucose and fat as energy. The
>>> percent use of fat GENERALLY goes up as intensity goes down. The percent use of fat, in the
>>> abcense of or low levels of glucose GENERALLY goes up. However it is my understanding that the
>>> metabolisation of fat is dependant on gluccose, IOW if glucose is very low teh body will switch
>>> to burning protein not fat. Of course this is fine for short periods of time as seme protein is
>>> available for burning, however, again my understanding, no real system is available for the
>>> storage of protein otehr than lean muscle mass so for longer period of excercise in which you
>>> end up burning protein it will come from muscle, not a good thing.
>>
>> Well, apparently, in the absence of carbohydrate input, the body goes into ketosis, which means
>> fat *is* being burned.
>
> Well here's an article on Ketosis. As the author said, I'll let you decide.
>
> http://www.cyberiron.com/nutrition/ketosis.html
>
> I'm sure there is any number of arguments that one could make the the body does "X" under
> "Y" circumstances. I suspect that most of these fairly extreme cases are not meant to be
> "normal body operating procedure". As mentioned earlier as the effort goes up so does
> glycogen consumption. I suspect that doing a hard workout 80-85% MHR whilst in a complete
> state of ketosis would prove to be difficult.

Yes, hard workouts are difficult.

>>> You can "train" your body to burn fat more effeciently, however you do not have to be in a
>>> satte of glycogen depletion in order to accomplish this. Simply lower the intensity and
>>> increasing teh duration fo a workout has a similar, probably not excatly the same, but
>>> similar effect.
>>
>> That increases the percentage of fat burned, not the amount of fat burned.
>
> If you want to increase the amount burnt simply workout longer. Low intensity for a long
> time.

Or higher intensity, shorter time.

>>> IMO, particulalary if the post from Larry is true, that swimming burns more glycogen
>>> percentile than does leg activies, it makes little or no sense to me to live and or workout
>>> in a glycogen depleted state. Without question certain organs and nervous system functions
>>> operate ONLY on glucose. So the body has certain safe guards to protect those organs. It
>>> just doesn't make sense to me to risk activating those safe guards searching for benefits
>>> that can gained in much safer methods. Of course this as usual is merely my opinion.
>>
>> ...except that we humans used to be basically meat eaters before farming.
>
> In your opinion. Some scientist believe we were not meat eaters as meat was a scarce resource and
> difficult to come by. My opinion is that we have always been omnivores...scavengers if you will.
> Eating anything that was available. Rotting meat, berrys, roots etc.
>
>> I don't think it is difficult for the body to make the glucose it needs. Most of the work done by
>> the body during a caveman day would be non-sprinting, right? so fat burning would work just fine.
>
> Depends. I suspect that we probably did alot of intermitant sprinting. Either away from preditors
> or later on after preditors while hunting. Also without doubt a great deal of our activities were
> at a much higher HR than what we do today. Climbing trees, mountains etc. Whether this was at
> 70%MHR + I don't know but to say we never burned glycogen is a bit of stretch.

But who said we never burned glycogen? Why do you raise that strawman?

> Not to mention that the brain and some organs burn ONLY glycogen. Also mister caveman was much
> more active than I probably spending many hours just gather food, not a 15 minute drive by at the
> local grocer. All in all I think glycogen depletion was a great problem for mister cave man as
> even slow movement burns a certain percentage of glycogen.

...and so, if he was not a meat eater, he would need to eat continuously to get enough calories.

>> The safeguards you are talking about are the normal operating mode for the body most of the time.
>> You might sprint through your day, but I don't.
>
> Sprinting is not the only means or need for Glycogen. Gylcogen is burnt constantly. However mister
> caveman woudl be lion lunch if he HAD to sprint and didn't have any. The option to not performing
> well was death...not just simply slower lap times.

...and that is why the body can make its own carbohydrate.

>>>> But that isn't what happens. When I am on the induction phase of Atkins, where I am eating very
>>>> little carbohydrate of any kind, my swimming is adversely affected, but I can still swim a hard
>>>> workout. So either the body must be able to replenish the glycogen from stored fat and protein,
>>>> or a swimmer can shift his energy cycle to the same one other athletes use just by not eating
>>>> carbs.
>>>
>>> The body not only can but must create glycogen in the abscence of eating them. As stated
>>> above certain organs and nervous system operates on Glycogen only. However the body cannot
>>> create them as fast as tehy can be eaten.
>>
>> That's a strawman, because the body only has to make them as fast as they are needed.
>
> Of course I agree. However this does not mean that the need cannot be greater than teh bodies
> ability to create glycogen. The body cannot create them fast enough to provide a complete muscle
> glycogen replishment before the next workout assuming a faily high level of gylocogen depletion.
> So over a period of a couple of days the muscle glycogen is depleted and performance suffers. Of
> course back to the idea that we are not talking about working out then we have no argument.

No, we are talking about not competing while trying to lose weight. we are not talking about not
working out while trying to lose weight. I've done it. As I reported, I was able to train hard while
trying to lose weight on a very low carb diet, but my top speed was adversely affected.

>> The problem for overweight people is precisely that they eat them faster than they are needed.
>
> No the problem is THEY EAT TO MUCH.

That is what I just said! Eating carbs faster than they are needed is eating too much!

> Not carbs not fat not protein. They eat to many calories PERIOD.

You should write a book about this fantastic new discovery that overweight people don't know about
and have never heard before. You'll be rich.

>>> And the systems your depending on when working out in a glycogen depleted state are no diffenret
>>> than any other athlete. However by not having glycogen availabale you have eliminate done system
>>> being available to you. Probably not good for performance.
>>
>> But we are talking about weight loss, not performance.
>
> I'm talking about diet. Diet as in what one should eat all of the time to lose weight, to maintain
> weight, to live.

But they aren't the same, even according to you.

> I frankly workout and need to perform while I'm working out. If I'm trying to lose weight I still
> need to perform. I'm quite surprised that in a swimming forum you would think the two are
> exclusive.

They are pretty much exclusive. If you were training for the Olympics, or for your city high school
champinships, do you think your coach would put you on a weight loss program a month before the
meet? Say no.

>>> As we are all an experimant of one you may be an individual that does well under lwo
>>> glycogen availability. However I suspect that a person could certainly find workouts that
>>> you could not do as well in a glycogen depleted states.
>>
>> But that's what I said. I said my swimming was adversely affected, but not so as I couldn't swim
>> a hard workout. I just didn't go as fast.
>
> Sorry must have miss read that. Saw "Isn't" instead of is. As stated before I guess I don't see
> the point. Why would one accept a lower level of performance rather than eat a diet that produces
> both weightloss and performance?

Because one can't perform at one's best while trying to lose weight. We are talking about overweight
people, people with 20, 40, 60 kilos to lose, not the guy who ate too much over Christmas.

> If we are disreguarding performance than yes, eat anything just as long as it's less than what
> you burn.

Thanks for staightening me out.

martin

--
If you are a US citizen, please use your constitutional right to vote, because we badly need a new
president.
 
C

Curt

Guest
This goes against what I feel is true. Don't know if you have read "Total Immersion" by Terry
Laughlin, but it is a good book IMHO. I was naturally a high cadence swimmer and am changing over to
less strokes and find that I am becoming much faster. I am in the water less for the same swim. If I
slowed down to the same speed when I was at a high cadence then the swim would become very easy and
my HR would be quite low. Hope I am making some sense. I feel a long efficient stroke is a better
route for a Triathlon to conserve energy. Longer glide and stroke. Getting into a nice rhythm (until
you get kicked in the head and elbowed in the ribs) and using a long full stroke would seem to me,
to pay off. You need to practice the full stroke for quite some time before it becomes really easy
for you. Meaning you are using muscles on that big finish and long stretch that you may not be used
to using and they may get tired fast until they get used to that style of swimming, so it may take
some time.

JMHO, Curt

"AW" <[email protected]> wrote in message news:[email protected]...
> Two swimmers, identical in size, strength, and overall swimming ability compete in an iron
> distance triathlon. Neither wears a wetsuit. Both complete the swim, 3.9k or 4,225 yds, in 55
> minutes. Swimmer A swims with
a
> long-forward, FQS stroke, and averages 2.50 meters per complete stroke
cycle
> (1.25m/hand splash). Swimmer B swims with a short, constant-pressure,
kayak
> stroke and averages 1.75 meters per complete stroke cycle. Both employ a minimal kick, and both
> breath every stroke.
>
>
>
> Which swimmer generates higher *peak* power during each stroke cycle?
That'
> s easy; swimmer A. The long-stroke swimmer covers a much greater distance with fewer strokes.
>
>
>
> Which swimmer uses more carbs during the swim? Swimmer A; the long-stroke swimmer burns more carbs
> in order to generate that higher peak power
during
> each cycle. Swimmer B, the constant-pressure swimmer, conserves momentum throughout the stroke
> cycle by maintaining a rapid, carb-efficient
cadence.
>
>
>
> Long-stroke, FQS swimmer A.think fast-twitch carb-eater.
>
>
>
> Short-stroke, constant-pressure swimmer B.think slow-twitch fat-burner.
>
>
>
> Which swimmer hits the wall at mile 23 of the run because they weren't
able
> replace those precious carbs they wasted during the swim? Swimmer A; the long-stroke
> swimmer bonks.
>
>
>
> I know, I know; you're going to tell me that the long-stroke swimmer, swimmer A, doesn't achieve
> higher peak power during a given stroke cycle. You're going to tell me that swimmer A has less
> drag and therefore can
cover
> the same distance as swimmer B, but with fewer strokes and less power. I don't buy it.
>
>
>
> Tether swimmers A & B with stretch cord. Don't allow them to kick, and
make
> them swim as far and as fast as they can for 1 minute. Both will achieve the same average
> distance. Swimmer B, the constant pressure, fat-burning swimmer, will max out on distance and hold
> steady. Even though Swimmer A, the carb-burning, long-stroke, FQS swimmer will achieve the same
> *average* distance, he or she will bounce repeatedly a little ahead of swimmer A & then get pulled
> behind.repeat, repeat, repeat. In other words, swimmer A
is
> unable to maintain a fixed position in the water. So, who's generating higher peak power during
> each stroke cycle???
>
>
>
> What are the implications of all this? Triathletes competing in
long-course
> & ultra-distance (1/2 and iron distance) triathlon would be well advised
to
> adopt a short-stroke, constant pressure, rapid cadence freestyle. I'd
have
> to say the same for open-water and postal swimmers competing in events longer than 5k. I doesn't
> makes a hill of beans worth of difference with respect to middle distance swimmers or sprinters.
>
>
>
> By the way, you could probably duplicate the tethered swim test with a
flume
> or a weighted swim-lift. What's interesting is to observe what happens to FQS swimmers when
> they're tethered or when they swim in an endless pool. They do one of two thing. They increase
> significantly their kick in order
to
> maintain their postion during the "dead spots" in their stroke, or they shorten their stroke. The
> longer they swim, the shorter their stroke becomes until they're no longer *bouncing*. They learn
> to kayak in order
to
> maintain a fixed position in the water; ie., in order to conserve
momentum.
>
>
>
> Thoughts?????