What cadence produces your highest FTP?

[doctorSpoc]

To quote R Chung, "cadence is a red herring"

Ric

RChung... says that "cadence is a red herring"... but torque at a given power absolutely necessitates a certain cadences.. so if you are using cadence or torque as your guide it's the same thing... in the absence of power he may have a point, but with a PM cadence is meainingful... as meaningful as torque because they are intrinsincly linked...

 

[doctorSpoc]

...there are benefits intrinsic to higher cadences which belance their relative inefficiency.

this is the point...

 

[frenchyge]

Lactic threshold is at a certain % of VO2 max. Sustainable power is limited by aerobic capaity. This is ABC stuff.

ABC stuff? Sustainable power is determined by the level of development of the aerobic energy production equipment within the cells, while pVO2max is determined by many systems external to the cells themselves. The relative % is not fixed by any means.

If two riders are both at 85% Vo2 max, the more efficient one will go faster.

I don't think that's universally true. VO2max is a measure of several systems working together, so if one rider's VO2max is limited by oxygen distribution, while the other's is limited by oxygen utilization at the cell level, it seems quite possible for their VO2max values to be identical, but their pVO2max (or even sub-maximal power) values to differ.

I am not advocating riding in lower cadences, just highlighting the implications of changes in efficiency.

...implications for systems that are input-limited, yes, but not necessarily for systems that are output-limited. See: mustang v. civic drag-race analogy from earlier.

Actually, as i pointed out earlier, given these implications, why are lessefficient cadences faster. The only reasonable conclusion is that there are benefits intrinsic to higher cadences which belance their relative inefficiency.

Or, that cyclists' power in the range of a couple hours is not limited by efficiency, as has already been postulated.

 

[peterwright]

ABC stuff? Sustainable power is determined by the level of development of the aerobic energy production equipment within the cells, while pVO2max is determined by many systems external to the cells themselves. The relative % is not fixed by any means.
I don't think that's universally true. VO2max is a measure of several systems working together, so if one rider's VO2max is limited by oxygen distribution, while the other's is limited by oxygen utilization at the cell level, it seems quite possible for their VO2max values to be identical, but their pVO2max (or even sub-maximal power) values to differ.

...implications for systems that are input-limited, yes, but not necessarily for systems that are output-limited. See: mustang v. civic drag-race analogy from earlier.

Or, that cyclists' power in the range of a couple hours is not limited by efficiency, as has already been postulated.

Now you're talking sense..

 

[mises]

Now you're talking sense..

Agreed. It's really only on longer 6+ hour rides that efficiency seems to become important to me. I have never finished an 11 hour ride with avg cadence higher than 80 in any terrain.

 

[jws]

There have been some posts about efficiency that show that it's misunderstood. The implications of some posts have been that we can somehow control efficiency with cadence or style.

Efficiency is mostly hard-wired and the variation within an individual is small and largely beyond our control. The best cadence varies with power, inertia, etc., but you're probably already using it.

Our minds are very good at integrating all the input from the body in finding the best cadence. All we have to do is let it happen.

 

[11ring]

Sure it is not fixed and can change through training, but don't think it can change instantaneously through pedalling style, i.e. there is no way for the same body to burn more fuel, demand more oxygen, create more CO2 and not go further over ones threshold.

It is not (completely) fixed in the short term but is fixed in the long term.

Threshold power = Metabolic capacity (Vo2 max) * threshold/vo2 max (for me only 77% aggh)* efficiency.

ABC stuff? Sustainable power is determined by the level of development of the aerobic energy production equipment within the cells, while pVO2max is determined by many systems external to the cells themselves. The relative % is not fixed by any means.


..

 

[JustCurious]

For your consideration.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=pubmed&cmd=Retrieve&dopt=AbstractPlus&list_uids=15923008&itool=pubmed_DocSum

 

[11ring]

This is completely back to front- should have written fixed in short term but not long term.

It is not (completely) fixed in the short term but is fixed in the long term.

 

[doctorSpoc]

There have been some posts about efficiency that show that it's misunderstood. The implications of some posts have been that we can somehow control efficiency with cadence or style.

Efficiency is mostly hard-wired and the variation within an individual is small and largely beyond our control. The best cadence varies with power, inertia, etc., but you're probably already using it.

Our minds are very good at integrating all the input from the body in finding the best cadence. All we have to do is let it happen.

No, no, no.. i think 11ring might be thinking the same thing... not physiological efficiency.. mechanical/biomechanical efficiency.. the act of pedalling faster even if it was a machine doing the pedaling is less efficient.. more friction from the bike and joints, the act of pedalling more means that you nessesarilly have to lift your legs through gravity more times a minute (this is significant), your legs disturb more air the faster you pedal (this is significant too), even down to our legs rubing against our seat more times a minute... pedaling faster from a mechanical/biomechanical point of view is absolutely less efficient than pedalling slower... but it would seem that there are phyisological benefits that outway the biomechanical/mechanical inefficiencies... just like in a car the faster the car goes the less efficient it is for similar reasons.. more friction, pistons and other parts of the engine need to be moved through gravity more times per unit time etc.. its the same thing..

 

[frenchyge]

... but it would seem that there are phyisological benefits that outway the biomechanical/mechanical inefficiencies...

If you and 11ring agree on that, then maybe one of you could explain how those benefits allow more power to be produced. As you say, the slower things move the more efficiency is theoretically available, but what does any of that have to do with power?

 

[doctorSpoc]

If you and 11ring agree on that, then maybe one of you could explain how those benefits allow more power to be produced. As you say, the slower things move the more efficiency is theoretically available, but what does any of that have to do with power?

i'm trying to figure out what 11ring is trying to say... in my last post i was just guessing that i thought that he thought as jws thought.. that when i was talking about efficiency i was talking about physiological efficiency when i was really talking about mechanical/biomechanical efficiency. "i think 11ring might be thinking the same thing [as jws]"

if higher cadence works as Dr Ferrari describes it (and yes he's closely associated drug use... but he is also happens to be arguably THE premier cycling physiologist/trainer in the world... that's why someone like Lance Armstrong for whom which money is no object (i've read that Ferrari takes 20% of salary) chose him.. warts and all)... as a "second heart" then i think the increased oxygen delivery capability and benefit is fairly obvious.. i.e. the inefficiencies i was talking about are mechanical/biomechanical but the benefit that offset them are physiological...

 

[frenchyge]

"i think 11ring might be thinking the same thing [as jws]"

Ok, I thought the opposite. That is, that 11ring were inter-mingling the two terms as jws suggested.

Bah! Maybe I'm the one that's confused.

 

[11ring]

I am referring to gross efficiency, power at crank/energy consumed. Or watts/kilojoules burnt per second. Under aerobic metabolism the ratio of kilojoules burnt to oxygen utilised should be constant between and across individuals. Hence more joules burnt = greater cardiovascular demand.

Ok, I thought the opposite. That is, that 11ring were inter-mingling the two terms as jws suggested.

Bah! Maybe I'm the one that's confused.

 

[11ring]

mistake again should be watts / joules per sec.

 

[11ring]

As in

"Two cyclists enter a hill climb or time trial. Both have the same VO2 max, but Cyclist A is more economical. They both ride at the same high speed. However, to reach and maintain this speed, Cyclist B must ride at a pace equal to 95% of his max VO2. Cyclist A, on the other hand, can ride the same speed, yet only be at 90% of his max. Should he pick up effort to 95%, he would out ride Athlete B and win."

"http://www.sharondonnelly.com/running/rw_news_frameset.html?http://www.sharondonnelly.com/running/news/rw_CTS_20040903_Burke.html


And "[font=&quot][/font]If you sit on a bicycle ergometer with the load set at zero and pedal at 80 rpms, you will discover that even though you are not doing any measurable mechanical work, your are still WORKING. It costs energy to just move your limbs, support your body, hold your balance, etc. The same is of course true for ANY movement, like running or skiing, or rowing. When this “unloaded cost of movement” is included in our measure of the mechanical work to energy expenditure ratio, then we get the GROSS Efficiency. Here, the word “gross” means “overall”, not “icky”. One factor that impacts gross efficiency is movement frequency. That can be cycling cadence, or rowing stroke rate, or stride frequency in XC skiing. Higher cadences tend to cost more energy in general. And heavier limbs have been shown to be less efficient to move. However, there is a balance such that trained athletes tend to zero in on an optimal cadence for their body type and anatomy. When they are pushed away from that cadence, they use more energy to do the same work. Therefore, it is important to realize that the ideal movement frequency is not a universal, but varies from individual to individual. So, you should not try automatically to mimic your training partner’s cadence if they are much taller or shorter, or more or less muscular than you. "

and

"If we take a group of cyclists, or a group of rowers and perform sub maximal testing on them to determine how much energy they consume when performing a standard sub maximal workload, we find that overall work efficiency will range between about 17 and 26%, with an average somewhere in the middle of that range. In other words for every 100 Calories of energy burned, we manage to convert 20 Calories of that energy to useful work on the pedals of the ergometer, or as pulling power on the rowing machine. Now, if your goal is to lose body fat during exercise, then I suppose it pays to be inefficient, since it is Calories burned that matter. However, if your goal is to move your body faster than the other guy, than being 25% efficient is way better than 18%! So, what are the sources of inefficiency and what, if anything can we do about them?"

http://home.hia.no/~stephens/effiperf.htm

 

[Alex Simmons]

Just for fun - indulge me....

See attached chart of a MAP test - which of the three cadence lines best approximates what actually happened?

 

[11ring]

I guess ... .the blue line rising.

Just for fun - indulge me....

See attached chart of a MAP test - which of the three cadence lines best approximates what actually happened?

 

[mikesbytes]

I guess ... .the blue line rising.

If that is the case, then higher cadence = higher wattage output.

Having said that I know that I can sprint faster in higher gears, ie with less cadence than I can in lower gears, ie with higher cadence.

 

[doctorSpoc]

If that is the case, then higher cadence = higher wattage output.

Having said that I know that I can sprint faster in higher gears, ie with less cadence than I can in lower gears, ie with higher cadence.

lower cadence than what?

i ride around at 100 rpms but for my max 5s power my rpms top out at ~140rpms in a ~53x15-16... you have to use a bigger gear or your cadence will be rediculously high...

what is your actual cadence when you are doing a maximal 10-15s sprint? just the mere fact that you are in a higher gear doesn't mean you cadence is low or high compared to say what you would normally be riding around at.. remember you are in a bigger gear but also going faster so you cadence could well be higher than your cadence you use for steady state..