## Torque, Cranks and FTP

A light bike doesn't replace good fitness.

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Rick
Posts: 2001
Joined: Sat Aug 29, 2009 4:30 pm
MTBers pedal slower, torque goes up, cadence goes down, power is unchanged.

Actually, I saw some references claiming that MTBers typically spin faster than road bikers, but of course they had selected a smaller gear. I can't remember where I saw it, but I noted that it was the opposite of what I had assumed and expected. When I tried mtb biking after years of road biking, I also noticed that higher RPMs in a lower gear where better at keeping my rear wheel from breaking traction.

But your point remains valid: torque and RPM always multiply to create power. One goes up the other goes down.

STARNUT
Posts: 3424
Joined: Sun Jun 19, 2005 6:43 am
Location: Hilly, Hot, and Windy
first off

a watt is a unit of work......

Watt = Force x Velocity. For us (bike geeks) its actually W= J/s = N • m / s = kg • m^2 / s^3. Or simply, Force in Newton Meters x Velocity in Meters per second.

"Torque" includes the length of the lever arm while the above removes that from the equation as it directly impacts both force and velocity simultaneously and inversely.

There has been a few studies, recently, that delt with crank arm length and peak power production in trained cyclist and power cranks (ie pedaling mechanics).

Id like to point out a person having a mass of 100 kilograms who climbs a 3 meter high ladder in 5 seconds is doing work at a rate of about 600 watts. It's more "effort" or "work" to get your ass off the couch than it does to ride a bike "hard" for the same amount of time. Granted, getting off the couch is a .5 second deal but still.

The short of the long is crank length means jack when it comes to power production.

Starnut
"Don't pedal harder, pedal faster!"
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LouisRooney
Posts: 55
Joined: Tue Jun 30, 2009 8:51 pm
All of this seems to fly in the face of my experience when cycling.

I don't have problems breathing hard or feeling my heart hammering away, I just can't turn the pedals fast enough/hard enough to make the bike go quickly.

To me this implies that my problem is muscular fatigue rather than lack of ability to pump the blood around my body. (Though possibly the main issue is lack of ability to deliver oxygen to my muscles rather than breathe it in.)

Nevertheless, there are no published studies that I am aware of that show one way or another if weights are beneficial or detrimental to cycling - there just isn't any proof one way or another.

Well we couldn't argue about it otherwise I guess -

Back OT - Torque/pedal force clearly is important, otherwise we wouldn't ride variable gear bicycles.

Tapeworm
Posts: 2585
Joined: Thu May 03, 2007 10:39 am
LouisRooney wrote:...I don't have problems breathing hard or feeling my heart hammering away, I just can't turn the pedals fast enough/hard enough to make the bike go quickly.

To me this implies that my problem is muscular fatigue rather than lack of ability to pump the blood around my body. (Though possibly the main issue is lack of ability to deliver oxygen to my muscles rather than breathe it in.)...

Indeed. Oxygen delivery for aerobic exercise is rarely the issue, at VO2max it is one factor. But what do you think is causing the muscular fatigue? And when you say you can't turn the pedals fast enough/hard enough why do you think causes this? Can you sprint? Can you "dance on the pedals" to get up a hill? If yes, then think why you can't sustain it.

LouisRooney wrote:Nevertheless, there are no published studies that I am aware of that show one way or another if weights are beneficial or detrimental to cycling - there just isn't any proof one way or another...

Actually there are a few which show a clear detrimental effect. There are some which show a possible benefit. However the question is: why indulge in a form of training which may or may not be of benefit when there are far more clearly demonstrated ways that DO work?
"Physiology is all just propaganda and lies... all waiting to be disproven by the next study."
"I'm not a real doctor; But I am a real worm; I am an actual worm." - TMBG

Rick
Posts: 2001
Joined: Sat Aug 29, 2009 4:30 pm
a watt is a unit of work.....

Actually, a Watt is a RATE of doing work.
A Joule is a unit of work: 1 Joule = 1 N * 1 meter
Rate of doing work is Power: 1W = 1 Joule/second

But I get your point. I am just trying to keep the terminology accurate.

Indeed. Oxygen delivery for aerobic exercise is rarely the issue, at VO2max it is one factor. But what do you think is causing the muscular fatigue? And when you say you can't turn the pedals fast enough/hard enough why do you think causes this? Can you sprint? Can you "dance on the pedals" to get up a hill? If yes, then think why you can't sustain it.

I agree that the "lack of strength" is often just an illusion. You don't have the "strength" because your cardiovascular system is exhausted (or limited).
But at least in my own case, I can't sprint either. In numerous interval sessions against other riders I just can't generate even the shortest bursts of enough power (force ?) to be competitive. Yet I have very good "relative" endurance and do well in extremely long races.

So it seems like each person has to assess his own weak points and strong points. In his "training Bible" Joe Friel said that he sees the greatest improvement in "power to the pedals" by weight training. It is hard to believe that he would be 100% wrong, even if it is not as important as he might think.

I am just discussing this; not 'arguing" any strongly held opinion. It does seem like the illusion of wanting a bit more leg strength is just too powerfull to relinquish.

Tapeworm
Posts: 2585
Joined: Thu May 03, 2007 10:39 am
Rick wrote:...In his "training Bible" Joe Friel said that he sees the greatest improvement in "power to the pedals" by weight training. It is hard to believe that he would be 100% wrong, even if it is not as important as he might think...

Unfortunately Friel is wrong quite a lot of the time. Proof that people can improve in spite of their training not because of it.

And its not usually the cardiovascular system that is the weak link, there are a whole host of other things which limit aerobic performance - mitochondrial density, ability to process metabolites, thermal regulation, delivery of energy/oxygen etc etc

Because the reasons WHY weight training may or may not be of benefit are still too murky to understand unless you really are trying to eek out that last 0.5% improvement there are many other ways that are clearly understood to improve aerobic performance. It is even argued by some that track sprinters don't need to go to the weight room. If this is true then comparing the forces per pedal stroke being used by a track sprinter (especially in the first ~5sec) vs a road time trial and there is quite a disparity ie: if a trackkie don't need then a roadie sure as hell don't.

For work I have to be able to move heavy things hence I spend a decent amount of time with weights. I wish they helped my FTP kick along but as to date it hasn't helped a bit. And they haven't helped my sprint either. (I will note that in a n=1 study of myself I was able to maintain Vo2max power by doing short anaerobic runs [Tabata protocol] and high rep weights for about 4 weeks, however, note it did not improve either, FTP went down and I was heavier.)

As mentioned, the reasons why it might be possible for weight training to improve aerobic performance have been greatly debated, everything from type IIa and/or IIx fibre conversion, hormone response, dis-inhibition of the golgi tendon organ, hyperplasia of type I fibres etc etc.

The fact that it is so debated, when compared to riding the bike a lot (one way or another), no one debates that this will improve your aerobic performance. So you can do one exercise which may, just a tiny bit, improve your performance, or you can do the one exercise which will see vast improvement. Of course there are many ways to "skin the FTP cat" but just about all will yield far greater improvements than weight ever can.
"Physiology is all just propaganda and lies... all waiting to be disproven by the next study."
"I'm not a real doctor; But I am a real worm; I am an actual worm." - TMBG

naisan
Posts: 216
Joined: Thu Oct 22, 2009 9:28 pm
kevinkalis wrote:So,
Would improving torque be something to train specifically to help increase power output without extra strain on the cardiovascular system? . . .
Any thoughts?

This whole question makes no sense. Just think about it - how are you going to increase torque?

With muscular work.

Can you work harder and not increase strain on your cardio system?

No.

naisan
Posts: 216
Joined: Thu Oct 22, 2009 9:28 pm
Rick wrote:But at least in my own case, I can't sprint either. In numerous interval sessions against other riders I just can't generate even the shortest bursts of enough power (force ?) to be competitive. Yet I have very good "relative" endurance and do well in extremely long races.

Rick, you seem to fit the classic picture of somebody with high endurance capacity but low absolute power. If you want it to change, train for durations and items you want to change.

Maybe you can improve those areas a little, maybe a lot depending on many factors. As we all get older, most of us also lose absolute power while not losing threshold power nearly as fast, so I don't want to ask you age, but it may be relevant.

Examine your goals, be realistic about where you're at (do some tests using a protocol such as what's presented by Friel, or in "training and racing with a power meter", and then build a training program.

naisan
Posts: 216
Joined: Thu Oct 22, 2009 9:28 pm
Listen to the tapeworm, skip the wights. He knows.

About the only exception I can think of is those who are getting over 40, and need weight work to keep muscle mass on their bodies as they age, and perhaps to keep bone density. These are general health concerns, and will not improve your cycling performance, rather they will likely hurt performance, but it may be better all around for fitness in the general sense.

an anecdote: my brother in law has great fitness, but not top high end power. He can lift more weight than me in squats, and does weight work, but I still have almost double the top wattage he does, and in all the riding and training we've done in the last few years, it's been about the same. I see huge gains in our fitness (FTP, let's say) from one time to another, but very little change in top end power.

Case in point - about 10 years ago I hadn't ridden a bike in over 10 years but hopped on one with a power meter at a fair, and produced about the same peak wattage I do now after almost ~2 years of regular riding.

Go ride your bike and enjoy.

Rick
Posts: 2001
Joined: Sat Aug 29, 2009 4:30 pm
Maybe you can improve those areas a little, maybe a lot depending on many factors. As we all get older, most of us also lose absolute power while not losing threshold power nearly as fast, so I don't want to ask you age, but it may be relevant.

Ha ha ! I am 60
It probably is relevant to my current situation, but it didn't seem much different even when I was younger.
Since I have been training for a long time, I feel like I know what actually works (for me), and it often seems to fly in the face of theory.
If I weight train, my short-term sprinting ability does go up, but my weight also goes up and my endurance and climbing go down. If I simply put on piles of miles, my endurance and climbing ability go up, but I believe it is primarily due to weight loss. My sprint deteriorates to nothing. In many races I felt like I was in an all-out sprint starting 30 seconds after the start, but luckily I could hold it till the end of the race. So if the race was very long and consistently hard, I could do "well", but still always miss the final break or am nowhere in the sprint. If the races is tactical, with lots of surging and gaps, I will be off the back quickly.
So I have always been very mediocre in racing (Cat 3). Even though I think I know what works best for me, it still doesn't really work well enough for great success, so I am always changing things a little and trying new programs.
What has always worked the best is the old "piles of miles" dictum. But of course right now it is winter and so I can't be on the road a lot. Another thing is that the "piles of miles" simply requires SOOOOOO much time that you can't do much of anything else but train, so I am always looking for a time-compressing shortcut. As soon as the weather gets a bit better, I will taper off the weights and substitute hill intervals. Windtrainer and/or roller intervals just don't seem to cut it.
Of course maybe there are just genetic and age limitations that can't be defeated.

naisan
Posts: 216
Joined: Thu Oct 22, 2009 9:28 pm
Rick wrote:Ha ha ! I am 60

When I get to 60, I will give you some advice.

In the meantime, sounds like you have a handle on the compromises you have to make, and now you have to choose!

I'm 20 years behind you, and even at this age already gave up on racing - been there, and now like to ride for pure enjoyment.

Have a blast, whichever methods you use.

BTW: for best results in shorter time, there have been some great threads on this board describing what weekly regimens people use, and that might be very helpful as well, as there are a great number of interval sessions described therein which might compress your training time. Many folks get by on 5-8 hours a week.

airwise
Posts: 1049
Joined: Tue Jul 27, 2010 8:31 pm
I hope no one minds me re visiting this but it's a question that is currently on my mind a lot.

At the moment I'm following the Giro and riding in the Dolomites and Austrian Alps. All climbs involve long (5-10km) stretches of 10% + gradients. After an hour or so I simply cannot generate normal power levels - nor can I stress my cardiovascular system as per normal.

For instance a couple of weeks ago I climbed Alpe d'Huez (ave c.8%) at 4.3 w'kg with ave HR of 163bpm. Yesterday I climbed Monte Crostis (ave 10.1%) at 3.2 w/kg with ave HR of 148 bpm. On both occasions I could not have gone harder. The difference was the cadence - substantially lower on the Crostis. But I could not sustain I higher power level as this would have required higher torque which was simply beyond me for 90 minutes.

So how does one gain the leg strength to maintain the levels I know I can climb at? People here seem to suggest it's not an issue but from my point of view in the real world it sure can be!

Tapeworm
Posts: 2585
Joined: Thu May 03, 2007 10:39 am
The answer lies in your question, you can generate the power but not sustain it. The reason for it can be a number of factors, production of metabolites (and their subsequent clearing), glycogen stores, thermal stress etc. If you could not sustain this kind of power for 10sec then I would say that strength is an issue. Anything else is because your body's systems for aerobic power cannot produce that power for any longer. This is more biochemical than biomechanical.

So the reason why your power was flagging on one climb was not because you lack an inherent strength.
"Physiology is all just propaganda and lies... all waiting to be disproven by the next study."
"I'm not a real doctor; But I am a real worm; I am an actual worm." - TMBG

airwise
Posts: 1049
Joined: Tue Jul 27, 2010 8:31 pm
But I can generate the power and sustain it for hours on a gradient of less than 9% - just not on those that require greater torque (ie. 10% +)

All other variables appear the same. Same bike. Same temperatures. Same fitness levels. The limiting factor appears to be my ability to sustain toerque levels in excess of 20 nm for long periods - ie 30 minutes plus.

So I'm none the wiser. The issue is a progressive loss of watts when the cadence drops below 70 rpm - this must surely be linked to torque? My HR is just 80% of MHR on these extreme gradients, but my legs can deliver no more. Is this what Sassi was talking about when recommending muscle building intervals?

Tapeworm
Posts: 2585
Joined: Thu May 03, 2007 10:39 am
Do you train at 70rpm? If not this can be an issue, maybe better gearing would be of use. What gearing are using?

I would like to see the power file when your power drops off.

It is possible that the contractile forces are so great that you are recruiting too many fast twitc muscle fibers but at 70rpm at threshold this would be unlikely.

So without more data I would say that simply your gearing is not sufficient for your level of fitness at these target gradients.
"Physiology is all just propaganda and lies... all waiting to be disproven by the next study."
"I'm not a real doctor; But I am a real worm; I am an actual worm." - TMBG

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