Are you sure that (a typical commercial) power meter could detect that difference?

As the metabolic cost is a function of power output and speed of muscle shortening, then if the crank length does not change and the power remains the same, a higher cadence causes faster muscle contraction for the same power, thus a higher metabolic cost for the same power.

Is this correct?

It's not a linear function. It's a function of speed and force.

No, but if it can't that's informative too.

Tuesday:

Avg watts: 125, cadence 106, HR 105


Last Thursday, did not feel like it helped recovery:

Avg watts: 141, cadence 90, Hr 112.




difference of 16 in cadence, and 16 in watts. felt far better after the high cadence day. Of note my typical rest day looks like the Tuesday, no the Thursday.

spinning at 120 vs a soft pedal at 70 will recruit different motor neurons at the same wattage. however the consequence has no bearing on what happens to the CV. Aside from _very_ high output situations your CV is going to be able to cover whatever the work demands of it. You are over thinking it at this point.

Self selection* :)



ETA: *within reasonable bounds!

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36 kona qualifiers 2006-'23 - 3 Kona Podiums - 4 OA IM AG wins - 5 IM AG wins - 18 70.3 AG wins
I ka nana no a 'ike -- by observing, one learns | Kulia i ka nu'u -- strive for excellence
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You keep talking about CV, but I'm talking about metabolic cost. I did mention heart rate earlier. But only to illustrate the greater metabolic cost for the same power of a higher cadence.

You agree the metabolic cost is greater at a higher than a lower cadence for a given power?

Or are you saying that the increased metabolic cost does not increase heart rate? Or are you saying the increased metabolic cost does not matter because there is enough ceiling in heart rate to easily absorb it?

Power is a function of speed and force and metabolic cost is a function of power and speed of muscle shortening / contracting, so I'm not sure what your point is.

Point is metabolic cost is not a linear function and doesn't just go up with increasing speed, so it's not correct that metabolic cost goes up with increasing cadence. There is an optimal cadence. Pedal faster or slower than optimal and metabolic cost increases.

Yes with you now. This might be of interest. Can't speak for the accuracy of the article, and I don't agree with pulling up on the pedals.

http://athletic-education.co.uk/...mal-cycling-cadence/


I'm not sure I want the discussion to shift to deliberate sessions in too big a gear.

But looking at the graph in the above article it does look as if 300 watts on a fixed gear, which necessitates being in too high or too low a gear most of the time, exept on the flat in the optimum gear, will 'feel' harder and require more energy. Yet it would score the same TSS as if an optimum gear were used on a geared bike.

Again for commuting, where speed may be limited, it may well be worth using a fixed gear to generate more training stress. Although it may not reflect in the TSS, you will have worked a little harder.

I would not recommend commuting in a gear which limits cadence though, better use a gear which encourages faster pedalling. Particularly if there are several stops, as excessive force will be needed to get up to speed and unless you are training for track starts in a kilo it wouldn't be worth the risk to muscles and tendons.

Again the old tradition of riding a fixed gear, which encourages fast spinning, through winter may have more merit than commonly thought.

 
Another article. http://burnhamcoaching.com/efficiency-and-cadence/


I'm not saying people should do their serious training in the wrong gear at less than optimal cadence or self selected cadence. Only at times where speed is limited, such as in a bunch or commuting, or training outdoors where conditions limit speed for safety reasons.

If you ride to work and home 5 days a week, over the year that is a lot of hours so all those extra turns of the pedals add up. Same watts, but a bit more metabolic stress and a bit more training benefit.

This confuses me - who are the 70+ athletes that don't use gears?

Why would there be a difference in 20 RPM between easy and hard cycling?
In my experience (analytical WRT myself and observational WRT to everyone I cycle with) cadence does not correlate with effort.

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People tend to self select a higher cadence for a higher power even if they are using gears. Optimal cadence tends to increase with power output.

I don't think adjusting cadence is a worthwhile method of varying training stress. I commute 10-11 hrs/wk and my daily TSS while commuting will vary from around 110 to 175 depending on how I feel and how hard I ride. Changing cadence up or down makes a very small change to training stress; it's much easier to vary power if you want to increase stress.

Yes which is why I mentioned when speed is limited for whatever reason, like safety commuting, riding in a group, at night, or when you want to keep power within certain limits. But there may well be other training advantages in using a higher cadence.

I just read this from Mark Allen. I'm not saying I agree with all he says here but I post it as some of what he says is interesting.

http://www.xtri.com/...temId.511708601.html


"Let's talk cadence. This has become a very hot topic and one that is worth exploring in your own training. If you watched the Tour de France for the past few years it would have been impossible to not notice a dramatic difference in the cadence (pedal turnover rate) between the eventual winner and that of the rest of the riders. As a triathlete your race demands are going to be different than for a stage cyclist, but nevertheless there is a lot you can gain from this technique that will help you out in a sport requiring three disciplines.

The theory behind higher cadence riding is that the length of muscle contraction is too short to build up as much lactic acid as in lower cadence riding. It is also suggested to facilitate the flushing of lactate better than a low cadence where the load on the leg muscle can be more constant. Low cadence in theory has less time during which the muscle relaxes and let's the flushing action take over. During the rest moments in the pedal stroke where one set of muscles relaxes and another takes over (normally around the bottom and top of the peddle stroke) is when the muscles can flush out lactate, and as a result keep up the power output.

Some people are suggesting however that not everyone is built to take advantage of this technique. Jan Ulrich, for example, said it didn't work for him because of his body type. I am not one to say whether this is true or not. But even if you are a person who for some strange reason cannot gain benefit from a higher cadence on the bike (and also running) of 90-95 revolutions per minute (rpm) it is a physiology worth attempting in your training. Here are some of the reasons…

First and foremost, your workouts should be designed around making race day seem like just another day of training. The closer your race can feel to a training day, something you have done thousands of times before, the less your body will perceive your race effort as a high stress situation. And one of the absolute keys to having your best race performance is to keep the stress level (perceived or real) as low as possible.

So how does this relate to high cadence training? To answer that let's think about how one feels during a normal aerobic training ride. Usually the cadence is relaxed (for most triathletes this means a cadence on the flats of around 80-85). However, when you get into a race, especially if it is an event shorter than an Ironman, cadence rates are elevated (85-90 and higher). This is one of the reasons training at a higher cadence can help you in your race. If you have trained at 90-95 rpms, this will eventually become your relaxed aerobic training cadence. Then when you are in your big race and still at a cadence of 90-95, it will feel just like another day training, which is a low stress signal to your body.

If you never do higher cadence training try this out. First purchase a cyclometer for your bike that can give you cadence feedback. Now go out and ride for 1-2 hours at a cadence of 90-95 rpms on a rolling course and keep your heart rate in the upper 10 beats of your aerobic training zone (the heart rate zone that you have for your long endurance workouts in each sport). If you are used to training at a lower cadence, the pacing of this turnover will feel exactly like the franticness of a race. Do this for a week straight and see if the higher cadence starts to feel more normal. Also, monitor how your runs feel each day after you ride like this. Almost immediately you should find that your turnover running will increase also. This is a good thing to have happen. World-class endurance runners usually have a cadence rate of 90-95 foot strikes counted on one foot per minute.

The end result is that you will start to ride at a higher cadence, and also you will be able to run at a higher cadence. This will help you out immensely in your races. It may get you to the finish line faster because of the lactate clearing effect. It will also get you to the finish quicker because it will train the neural pathways from your brain to the muscles that cause muscle contraction. And just like training your fat and carb metabolic pathways, one needs to build efficiency between the brain and the muscle. And the best way to do this is through higher cadence training. In fact, a lot of the fatigue that one feels in long events such as an Ironman is a tiring of those exact pathways. You may have all the calories you need, but the link between the gray matter and the red matter is fatiguing. The more this is trained, the less it will fatigue when it counts.

This type of training is especially important during your base period when workouts are done at lower speeds than they will be done at during your interval sessions near the races. As I have said many times over the years, just because you are training slower does not mean you need to look like you are training slower. So even at very easy training paces, if you keep your cadence rate up, the timing of muscle firing will give you the neural fitness you need to transition into speed work without a hitch. If you train at 75-85 rpms in your base but then suddenly try to up it to 95 during speed work, your body will have a tough time responding because you are asking it to do two things: go faster and go at a higher cadence. But if you lay the foundation needed to make higher cadence seem normal during your base work, then the only thing that will change in the speed phase is an increase in speed during your interval sessions.

I hope this is food for thought. "

My cadence is always much higher in a crit than just noodling around. I'm presuming because there are many Supra Threshold efforts where it's just more comfortable to ride at a higher cadence than increasing force on the pedals. 600W @ 90 RPM requires a peak force of around 170lbs on the pedals. Increasing cadence to 100-110 reduces that force.

This I get and agree with.
I've done a few cirts lately and see my cadence vary from 85-105 RPM - this positively correlates to power but only because of the nature of the accelerations; there is no time to change gears sprinting out of a corner.

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Fast pedalling might also make you more efficient.

http://www.active.com/...lists-more-efficient

self optimized to even the torque

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36 kona qualifiers 2006-'23 - 3 Kona Podiums - 4 OA IM AG wins - 5 IM AG wins - 18 70.3 AG wins
I ka nana no a 'ike -- by observing, one learns | Kulia i ka nu'u -- strive for excellence
Garmin Glycogen Use App | Garmin Fat Use App