Power Meters and Pedaling Effectiveness

[RapDaddyo]

as far as i'm aware the Polar left right balance doesn't *measure* this as you'd need force instrumented pedals to capture such data accurately.

I assumed that the Polar was measuring this, through an interpolation software algorithm. They interpolate power through chain tension and they know the position of the crank through the cadence magnet. Why can't they compute an interpolated force being applied to the crank throughout the stroke?

where have you been for the other five TdF's ;-)

I just didn't notice it.

and other riders who have won 5 TdF or other races may or may not pedal at super high cadences

I'm not implying that his is the best technique for all riders, only that he must have seen a benefit to have worked hard to develop his technique.

bike position is something else, and wasn't what any of us were including while talking about pedalling

To me, bike position is just a part of technique. Maybe more important than others, but just one of the variables I have control over and therefore something to try to optimize.

 

[ric_stern/RST]

To me, bike position is just a part of technique. Maybe more important than others, but just one of the variables I have control over and therefore something to try to optimize.

Not "maybe" - definitely more important. Possibly the most important variable. I don't think anyone would disagree that it isn't something to optimise.

 

[RapDaddyo]

Not "maybe" - definitely more important. Possibly the most important variable. I don't think anyone would disagree that it isn't something to optimise.

Okay, but the brain is a pretty powerful computer -- the first parallel processing supercomputer ever built. Maybe it's arrogance, but I feel like I can think about more than one thing at a time, even work on more than one thing on a ride. Surely you aren't saying that none of the rest of what I called "technique" matters, are you?

 

[ric_stern/RST]

Okay, but the brain is a pretty powerful computer -- the first parallel processing supercomputer ever built. Maybe it's arrogance, but I feel like I can think about more than one thing at a time, even work on more than one thing on a ride. Surely you aren't saying that none of the rest of what I called "technique" matters, are you?

I believe i've responded to all the "technique" issues you've mentioned.

Ric

 

[acoggan]

If you have a power meter, then yes, i feel that HR and cadence info isn't that useful. I'd take a HR monitor for training prescription versus nothing at all (i think, and i hate to speak for others, that this maybe different to AC...?). Hopefully, AC will chime in on that aspect and maybe about EB.

I think it depends in part on whether you're the coach or the coachee...if I were coaching somebody else, then I might want them to use a heart rate monitor vs. nothing at all (i.e., going by perceived exertion). OTOH, I don't see heart rate as a substitute for perceived exertion, and for inexperienced athletes use of a heart rate monitor seems to often get in the way of developing/honing perceived exertion. The same, I think, can be said for monitoring of cadence: useful in some situations/individuals, but detrimental if people become overly focussed on it.

 

[ric_stern/RST]

I think it depends in part on whether you're the coach or the coachee...if I were coaching somebody else, then I might want them to use a heart rate monitor vs. nothing at all (i.e., going by perceived exertion). OTOH, I don't see heart rate as a substitute for perceived exertion, and for inexperienced athletes use of a heart rate monitor seems to often get in the way of developing/honing perceived exertion. The same, I think, can be said for monitoring of cadence: useful in some situations/individuals, but detrimental if people become overly focussed on it.

Right, so, i was wrong in what I thought you'd prescribe, but 'correct' in that we both do the same thing (or you would do)!

 

[squidwranglr]

Now that's funny! I hear golf is a no brainer too.

Boy, if you think cycling technique can be a complex issue, wait till you hear about swimming...

Berend

 

[RapDaddyo]

Boy, if you think cycling technique can be a complex issue, wait till you hear about swimming...

Berend

Actually, I know. My daughter raced (specialties fly and free) for 10 years. My comment was made tongue-in-cheek.

 

[squidwranglr]

Actually, I know. My daughter raced (specialties fly and free) for 10 years. My comment was made tongue-in-cheek.

Mine was quite tongue-in-cheek, too! I figured the "boy, ..." prose would have given it away, but maybe I should have added a smiley.

Berend

 

[RapDaddyo]

I think it depends in part on whether you're the coach or the coachee...if I were coaching somebody else, then I might want them to use a heart rate monitor vs. nothing at all (i.e., going by perceived exertion). OTOH, I don't see heart rate as a substitute for perceived exertion, and for inexperienced athletes use of a heart rate monitor seems to often get in the way of developing/honing perceived exertion. The same, I think, can be said for monitoring of cadence: useful in some situations/individuals, but detrimental if people become overly focussed on it.

I understand and accept what you are saying about HR. It's better than nothing. But, on the cadence issue, it still flies in the face of my own experience. Granted, I did my serious cycling before the availability of power meters, but I distinctly recall that other than just spending a lot of time on the bike, there were three things that were hard to learn to do and two of them were technique issues. One was spinning smoothly and with little effort at a high cadence (100+). Two was long climbs on the saddle. Three was sprinting, again largely because of the high cadence because you just run out of gears. I clearly remember working on these techniques until I wanted to puke, but they made me a competitive rider. They were absolutely not natural nor did I feel comfortable doing them initially. They were learned, or so it seemed to my naive mind.

 

[ric_stern/RST]

I understand and accept what you are saying about HR. It's better than nothing. But, on the cadence issue, it still flies in the face of my own experience. Granted, I did my serious cycling before the availability of power meters, but I distinctly recall that other than just spending a lot of time on the bike, there were three things that were hard to learn to do and two of them were technique issues. One was spinning smoothly and with little effort at a high cadence (100+). Two was long climbs on the saddle. Three was sprinting. I clearly remember working on these techniques until I wanted to puke, but they made me a competitive rider. They were absolutely not natural nor did I feel comfortable doing them initially. They were learned, or so it seemed to my naive mind.

perhaps the extra training promoted an increase in fitness which accounted for your change in performance, rather than some change in 'technique'?

 

[RapDaddyo]

perhaps the extra training promoted an increase in fitness which accounted for your change in performance, rather than some change in 'technique'?

Maybe so. But, I sure recall that each one got easier when I discovered a technique that allowed me to do each with somewhat less exertion. Technique development didn't enable me to do them, but it did enable me to survive them. I think I can say that with certainty about spinning. I don't think it was fitness that got me to be smooth in my saddle at 125-140 cadences, which was one of my drills. I know that it was when I learned to stop pushing through the bottom. Low cadence work wouldn't have ever taught me to do that, because I didn't bounce at cadences below 100.

 

[RapDaddyo]

Mine was quite tongue-in-cheek, too! I figured the "boy, ..." prose would have given it away, but maybe I should have added a smiley.

Berend

No problem. By the way, I agree with you. My daughter doesn't know it but I tried and tried to learn the porpoise kick in the fly and never did get it. I decided one is born with that or not -- I wasn't.

 

[beerco]

I understand and accept what you are saying about HR. It's better than nothing. But, on the cadence issue, it still flies in the face of my own experience. .

That's 'cause you don't have a powemeter yet. I'm no ex-phys or anything but I have been training with a PM for about 4 years now. The most striking thing I've learned is that really it's only the power that maters. I don't wear an HR strap anymore and I haven't checked my cadence in a long time...in spite of that I'm still able to go faster than many on less hours than my peers who worry about spin, base miles etc.

p.s. Andy C - you never let me know if you received my NP "busting" file or not.

 

[RapDaddyo]

That's 'cause you don't have a powemeter yet. I'm no ex-phys or anything but I have been training with a PM for about 4 years now. The most striking thing I've learned is that really it's only the power that maters. I don't wear an HR strap anymore and I haven't checked my cadence in a long time...in spite of that I'm still able to go faster than many on less hours than my peers who worry about spin, base miles etc.

Great. I look forward to finding out what it's like to train with a PM. And, thanks for taking the time to share your insights. By the way, which PM do you use? I haven't seen many comments about the SRM Amateur model. Most people who have the SRM seem to have the Pro model. I wonder why?

 

[beerco]

Great. I look forward to finding out what it's like to train with a PM. And, thanks for taking the time to share your insights. By the way, which PM do you use? I haven't seen many comments about the SRM Amateur model. Most people who have the SRM seem to have the Pro model. I wonder why?

I use a power tap. I used to have a polar but found the reading unreliable at times...not something I like to have.

The SRM amateur is only slightly better than the polar in terms of accuracy and precision - that unit only uses two strain gauges and often times has non-linearities in its torque response. (I should say that it may be inaccurate - some are good and some are bad. Some amature users have reported contacting SRM and getting a "well, what did you expect?" as their response)

The pro on the other hand has eight gauges, just like the powertap and seems to work pretty well. Most pro users who know what they're doing calibrate them often though as sometimes they drift too. (powertaps are not calibratable by the user so....we just pray that they stay accurate!).

When people ask me I usually recommend the powertap as it seems to be a no-muss no-fuss solution at a reasonable price. I'd stay away from the new PT-SLs for a while though until they get the manufacturing bugs worked out of them. If you've got money to burn, go ahead with the SRM pro.

 

[squidwranglr]

No problem. By the way, I agree with you. My daughter doesn't know it but I tried and tried to learn the porpoise kick in the fly and never did get it. I decided one is born with that or not -- I wasn't.

You know what they say about the fly? There's no such thing as recreational fly swimming! I'd be happy if I got my freestyle technique down.

I've been doing triathlons for about a year and a half now and without any doubt, swimming is where improvement has come the slowest. Technique is so fundamental to swimming efficiently when compared to cycling or running. This is where Ric's argument about restricted axes of movement in cycling come into play. In swimming (freestyle), so many parts of your body have to move in synchronicity and there's absolutely no external structure that couples their movement (like, say, the opposing crank arms on a bike) and every little bit of dead spot in the motion can add to your drag in the water. Your torso rotation, elbow angle, wrist angle, ankle flexion all have tremendous impact on your net efficiency.

Yeah, I think my passion will stick with cycling. Swimming will keep being that thing I "have to do" before cycling and running.

Berend

 

[RapDaddyo]

You know what they say about the fly? There's no such thing as recreational fly swimming! I'd be happy if I got my freestyle technique down.

I've been doing triathlons for about a year and a half now and without any doubt, swimming is where improvement has come the slowest. Technique is so fundamental to swimming efficiently when compared to cycling or running. This is where Ric's argument about restricted axes of movement in cycling come into play. In swimming (freestyle), so many parts of your body have to move in synchronicity and there's absolutely no external structure that couples their movement (like, say, the opposing crank arms on a bike) and every little bit of dead spot in the motion can add to your drag in the water. Your torso rotation, elbow angle, wrist angle, ankle flexion all have tremendous impact on your net efficiency.

Yeah, I think my passion will stick with cycling. Swimming will keep being that thing I "have to do" before cycling and running.

Berend

I hadn't heard that about the fly, but it's true. And I agree with you about cycling vs. swimming. Anyway, I'd rather come in from my workout smelling like diesel fuel rather than chlorine.

Paul

 

[RapDaddyo]

I use a power tap. I used to have a polar but found the reading unreliable at times...not something I like to have.

The SRM amateur is only slightly better than the polar in terms of accuracy and precision - that unit only uses two strain gauges and often times has non-linearities in its torque response. (I should say that it may be inaccurate - some are good and some are bad. Some amature users have reported contacting SRM and getting a "well, what did you expect?" as their response)

The pro on the other hand has eight gauges, just like the powertap and seems to work pretty well. Most pro users who know what they're doing calibrate them often though as sometimes they drift too. (powertaps are not calibratable by the user so....we just pray that they stay accurate!).

When people ask me I usually recommend the powertap as it seems to be a no-muss no-fuss solution at a reasonable price. I'd stay away from the new PT-SLs for a while though until they get the manufacturing bugs worked out of them. If you've got money to burn, go ahead with the SRM pro.

Actually, I was considering the SL. Are you saying that you know there are manufacturing bugs in the SL, or are you saying there "must be" manufacturing bugs because every new product has them? What are the bugs?

 

[beerco]

Actually, I was considering the SL. Are you saying that you know there are manufacturing bugs in the SL, or are you saying there "must be" manufacturing bugs because every new product has them? What are the bugs?

Yes to both. The SLs seem to have started out o.k. and then it seems some parts came in out of spec and many had to be recalled. I can't afford an SL right now so haven't been following very closely on what the current **** is. Call 'em up and find out.