In article <
[email protected]>,
"Phil Holman" <piholmanc@yourservice> wrote:
> "Tim McNamara" <[email protected]> wrote in message
> news:[email protected]...
> > In article <[email protected]>, "Phil
> > Holman" <piholmanc@yourservice> wrote:
> >
> >> "Tim McNamara" <[email protected]> wrote in message
> >> news:[email protected]...
> >> > In article <[email protected]>, "Phil
> >> > Holman" <piholmanc@yourservice> wrote:
> >> >
> >> >> "Tim McNamara" <[email protected]> wrote in message
> >> >> news:[email protected]...
<snip>
> >> >> > My understanding- which may not be correct- is that VO2 max
> >> >> > is biologically determined and that training does not
> >> >> > significantly change this.
> >> >>
> >> >> I'll assume you are talking about a theoretical ceiling and not
> >> >> the difference in the same athlete being in shape and not in
> >> >> shape. The theoretical ceiling is biologically determined but
> >> >> what biologically constitutes that ceiling is still up for
> >> >> discussion.
> >> >
> >> > As I understand it (it's been a while since I had any reason to
> >> > look into this stuff and maybe new data has come to light in the
> >> > interim), if your VO max is 60 ml/kg/min then that is basically
> >> > it.
> >> > You can't "train up" your VO2 by 15.6% at least from the data I
> >> > had looked at a few years back.
> >>
> >> I'll resist the urge to challenge your understanding on the basis
> >> of a rider who loses 5 kg of body weight. When dealing with PCs,
> >> we are not interested in that aspect of any VO2Max improvement.
> >
> > That's good, because of course PowerCranks would have no different
> > effect on this than any other cranks. That's simply a matter of
> > weight loss.
>
> There is the argument that any improvement means the previous value
> wasn't the true max.
Hmmm, I suppose but then we assume uncontrollable variables that make
the comparative measurements useless.
<snip>
> > VO2 is not the sole determinant of athletic performance- if it was,
> > all we'd have to do is measure VO2 max and we'd know the winner.
> > However, given that the literature used to indicate that VO2 was
> > basically genetically determined- whether that is still the case I
> > don't know- it seems highly unlikely that one can train up one's
> > VO2 by 15.6%.
>
> http://www.ncbi.nlm.nih.gov/sites/entrez?Db=pubmed&Cmd=ShowDetailView&
> TermToSe
> arch=16876479&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.P
> ubmed_RV AbstractPlus
>
> I think you've interpretted theoretical ceiling improvement to mean
> the normal kinds of improvements seen by athletes who employ new
> training techniques etc. Once again the "any improvement means the
> previous value wasn't the true max" argument applies.
Thanks for the cite. There were too many jargonicious terms in that
abstract for me to sort out at 11:24 PM on a Sunday night. They're
probably transparent to a physiatrist or exercise physiologist.
<snip>
> >> > Of interest to me would be whether whatever benefits are gained
> >> > from PowerCranks are durable. When people go back to regular
> >> > cranks for racing, do the maintain the neuromuscular pattern
> >> > that a PowerCrank is supposed to develop? Or do they go back to
> >> > normal riding quickly? Do they have to "brush up" with the
> >> > PowerCranks periodically? My hunch is that the muscle
> >> > recruitment pattern is quickly unlearned and the rider goes back
> >> > to a normal pedal stroke within a week or so after returning to
> >> > using normal cranks.
> >>
> >> From my experience, it's subject to the same reversible process as
> >> regular training. How much fitness do you think you'll lose in a
> >> week? I haven't pedaled a PC in about 3 years but I can still
> >> employ the technique for sustained periods because I still
> >> maintain the riding technique with regular cranks.
> >
> > The purported unique benefit of PowerCranks is as much neurological
> > as muscular. The rider has to develop a different pattern of
> > muscle recruitment and develop new "muscle memory." That pattern
> > of muscle recruitment is not necessary on regular cranks, and I
> > suspect that the new pattern would be lost quickly- perhaps in a
> > couple of rides.
>
> Now why would you think that? I can't think of one skill I've learned
> that has significantly diminished and especially not in a week. Do
> you suspect a loss in the ability to play the guitar in a week?
My comment on this comes out my background in psychology. I don't have
a formal background in the sub-field of kinesiology- which would be
relevant to the discussion- so it's quite possible I've got it wrong.
The nervous system learns muscle recruitment patterns through repetition
and indeed part of the training of any sport with repetitive movements
is to refine that recruitment pattern. The pattern is maintained with
repetition and decays with disuse. If you've had enough repetition,
then you'll pick it back up quickly.
I play guitar and the difference in my chops is noticeable to me if I
don't play for a day. If I don't play for a couple days, it's painfully
noticeable. If I didn't play for three days, you'd notice. If I don't
play guitar for a week, which happens sometimes during the summer when I
go out for a bike ride right after work and don't come home until dark,
it takes me an hour or more of running scales and going through chord
progressions to regain my customary level of fluency, for example. And
I don't have to play a lot- a half hour a day or so- to maintain the
motor skills (the creative skills are another matter
).
In the case of PowerCranks, my thinking is this: the average racer who
buys these will already have had years of training on regular cranks
with millions of repetitions of the pedaling motion. Average Racer buys
the PCs, puts them on his bike and diligently follows the training
protocol. He learns to lift his legs up and over the top of the
rotation and into the power stroke. He rides with the cranks enough to
develop the new muscular recruitment pattern and doesn't have to
consciously think "up and over" with each pedal stroke. Thus he gains
the signal benefit of PCs, which is that the leg pushing down through
the power stroke isn't being resisted by the weight of the rising leg
coming up through the rest stroke.
Well and good. But in races and on group rides, he might switch to a
bike with regular cranks due to various reasons. Now he doesn't have to
lift that rising leg any more, and the long-established "normal" pattern
of muscle recruitment would probably tend to rapidly reestablish itself-
just like guitarists lapsing back into a familiar pentatonic scale in a
performance setting rather than playing the Mixolydian scale that
they've been learning to use in rehearsal. The question to me is "how
durable is the new pattern of muscle recruitment" when the rider returns
to normal cranks. An hour? A day? A week? A month? Once the pattern
is established, does the rider have to use the PCs daily to maintain
those cited gains in efficiency?
I could readily imagine the rider falling back into a normal pedaling
muscle recruitment pattern within 30 minutes. But I could also be
entirely wrong on that, or there may be quite a bit of variety on a
case-by-case basis.
Interestingly PCs are the reverse of riding a fixed gear. The old
belief is that fixed gear bikes are good for your spin. My experience,
and that of most of the folks I have asked that do fixed gear winter
training, is that when you get back on the freewheel bike you're
pedaling squares and your spin is worse. The fixed gear's ability to
raise the rider's leg with the momentum of the bike- which is part of
what makes a fixed gear feel easier to ride than a freewheel gear of the
same development- changes the muscle recruitment pattern fairly quickly.
I've noticed it after a single midsummer fixed gear ride.
So, in a roundabout way, that's why I would think that. Sorry for the
excess verbosity and rather nonlinear approach to answering your
question.
> This part of the debate is much like arguing tire RR with those that
> haven't read the article. I'm sure you can relate.
I'm sorry to be a drag on the discussion.
