4 ms·

> The idea that your muscles have enough strength on the upstroke to contribute meaningfully to cycling is actually a bit of a misunderstanding. Absolutely not

> The idea that your muscles have enough strength on the upstroke to contribute meaningfully to cycling is actually a bit of a misunderstanding. Absolutely not, and there are plenty of easy counterexamples. If you've ever raced track, team pursuits start from a dead standstill. You have to expend a ton of force to turn a huge gear, and the contribution of the lifting leg is crucial to getting up to speed. Of course it's not going to contribute as much as your lead leg, but all four of your limbs are at maximum exertion getting the bike up to speed. Even not racing at a track, you can test this on any road bike. Shift into high gear, come to a standstill, and time yourself getting up to speed. Another trivial counterexample that anyone (with clipless pedals) can test is a hill climb. Being able to lift on the upstroke is an enormous additional benefit and the difference can be easily measured and proven. Perform a lengthy climb with and without involving your trailing leg, at a given level of intensity. Repeat this multiple times, and it will be patently obvious that your trailing leg is performing significant useful work. The steeper the climb, the more important this is. Sprint finishes are another place where this is critically important, but it's harder to set up a simple test. What all of these have in common are situations where outputting a higher force is more important than long-term endurance. Lifting on the upstroke is difficult to do at high pedal speeds, but at medium or low pedal speeds, it's a clear differentiator.

rhn_mk1 3y ago
Those are not necessarily examples of lifting. Those could as well be explained by the contribution of not pressing on the opposite pedal (to keep the foot from sliding). And not pressing doesn't shine any light on the force of lifting.
- louthy 3y ago
  > to keep the foot from sliding The foot doesn’t slide with clipless peddles. The foot is locked in position. And you can absolutely use lifting and pushing combined - I have done this many times on long sportives (~100 miles); it can give respite to the ‘pushing’ muscles
- tourist2d 3y ago
  > to keep the foot from sliding So you obviously have never used clip in bike pedals before. Why are you trying to argue this point if you know nothing about what you're talking about?
  - hinkley 3y ago
    We are perhaps not the best group on the internet for discussing biomechanics...
  - rhn_mk1 3y ago
    If you're clipped in, why would you keep feet from sliding? Preventing sliding by pushing is how effort is wasted and is a possible explanation why a cyclist might feel much stronger when clipped in and no longer has to push - while attributing the lower effort to the upstroke pull.
- stouset 3y ago
  > Those are not necessarily examples of lifting. They are, and this is trivially demonstrable by literally just trying it on a bike. Seriously. Go put a road bike in the highest gear and try to get up to speed from a standstill. Not only will you be pulling up on the rear pedal, but you’ll be using your arms to try and wrench the handlebars off the stem too. Go climb a steep hill. Same thing occurs. It’s not like this is subtle. The contribution of your rear leg very clearly contracting will be impossible to miss.
jeffbee 3y ago
We have a large amount of power meter data demonstrating that elite and pro cyclists do not, in fact, exert much force on the rising stroke when in the saddle. They maintain a net downward force on the pedal most of the time. The benefit of clipless pedals is repeatable positioning and the ability to start the downstroke right at top dead center, without slipping off the pedal. The benefit is not from powering the backstroke.
- hinkley 3y ago
  Personally outside of dramatic moments like the Big Hill or the club smartass trying to drop everyone for giggles, driving through the bottom of the stroke was the only thing that felt like it 1) mattered and 2) could be sustained. But I think you have to go to triathletes to really see that effect more pronounced. Since they like to sit tilted a couple degrees farther forward on the bike, the hamstring is more accessible. At the end of the day a pro is 5-10% better than a serious cyclist at five different things. Even before you get to diet and genetics (and doping, sorry) they’re already outputting more watts and getting more of them to the wheels than I could hope to. Technique adds up.
- stouset 3y ago
  Yet cycling events are frequently won out of the saddle on the slopes or out of the saddle in the sprint. And yes, sometimes they’re won by someone time trialing away from the pack while in the saddle. But even then, most of the time it’s a breakaway pack which fights for the podium in an all-out sprint.
  - hinkley 3y ago
    The breakaway pack also typically sprints away from the peloton. Because drafting is 30% easier than riding at the front. If you don’t catch a wheel as it goes past, you’re dropped. I’m looking around at all this ”data that we have about pedal strokes” and nobody mentions sprinters or climbing specialists. If they don’t know it’s important they won’t test for it. Sounds like “science” being done by domain neophytes and called objective. What is interesting though is that one claimed that advanced amateurs have higher peak stroke torque than pros. Pros are spreading more power out over a larger arc of the circle. Now that could still be 130° of the stroke for all I know but that still sounds like circularizing to me. I also haven’t found anyone yet who says LeMond was wrong about driving through the bottom of the stroke, which is how I rode.
hinkley 3y ago
> but all four of your limbs are at maximum exertion getting the bike up to speed. Oh goodness yes. When you’re going full out it’s like you’re trying to wring water out of a steel towel. Pull up on left handlebar while using right arm to prevent oversteer. Another fun failure mode is when you don’t quite trust your handlebars. I’m either not going to pull on these or I’m gonna stop before the Big Hill to find an Allen wrench and tighten these stupid things. I think the new design is meant to prevent a lot of that.
- stouset 3y ago
  > trying to wring water out of a steel towel I’m stealing this! Spot on.
jdietrich 3y ago
>the contribution of the lifting leg is crucial to getting up to speed This might feel true, but it isn't. Buy or borrow a dual-sensing power meter (Garmin Rally, SRM X-Power etc) and you can see for yourself - there's practically no useful power in the upstroke. Toe clips or clipless pedals can extend the power stroke, but only by a few degrees at the bottom of the stroke. https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-upstroke-2 https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-up... The intuition of cyclists is a very bad indicator of actual performance. For decades people thought that hard, narrow tyres were faster, but nobody had actually tested it properly. Narrow tyres have lower rolling resistance on a smooth steel drum in a test lab, but they have much higher rolling resistance on real roads with bumps and ruts. When paired with suitable rims, the reduction in rolling resistance of wider tyres more than compensates for the penalty of increased weight and drag.
- ordu 3y ago
  My cyclist's intuition says that leg clipping allows you to extort greater force on a down stroke. Without clipping the force is limited by your body weight, with it the only limit is your muscles. Thinking about it your hands and a back leg allow you to apply a lot of downward force to your body and your lead leg can add all this force to a stroke. It doesn't matter that your hands or back leg individually are not so strong when pulling, because their efforts are combined. In situations when you need not to extend as much force as you can, probably clips do not add much, though I do not know. I tried at some point to ride a bicycle without clips and nearly failed. My back leg tries to pull and leave a pedal. > https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-upstroke-2 https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-up... They are saying that with high rpm cyclists do not pull. I can believe that, high rpm is beneficial exactly because you need to apply a relatively small force.
- stouset 3y ago
  I strongly encourage you to actually test this yourself. Having personally done so myself, all I can say is that you will be surprised. Time yourself on a max-effort sprint in a high gear from a standstill. Don’t pull up on half your efforts. Pull up on half your efforts. The effect isn’t subtle. I’m not particularly convinced by power meters not showing much here. The biggest reason being that pulling up has the effect of allowing you to push even harder down. Without pulling on the handlebars or pulling up on the rear pedal, the maximum force you can exert on the pedal is a function limited by your weight. By pulling up on those three points, your ability to push down harder is significantly greater. Another simple counterexample is hills. There exist hills in my city that are physically impossible to climb without clipless pedals. You can stand on the pedal all you want, but your body weight is not enough to overcome the downward pull from the slope. On clipless pedals, while pulling up, you can climb the hill.

rhn_mk1 3y ago

Those are not necessarily examples of lifting. Those could as well be explained by the contribution of not pressing on the opposite pedal (to keep the foot from sliding). And not pressing doesn't shine any light on the force of lifting.

louthy 3y ago
> to keep the foot from sliding The foot doesn’t slide with clipless peddles. The foot is locked in position. And you can absolutely use lifting and pushing combined - I have done this many times on long sportives (~100 miles); it can give respite to the ‘pushing’ muscles
tourist2d 3y ago
> to keep the foot from sliding So you obviously have never used clip in bike pedals before. Why are you trying to argue this point if you know nothing about what you're talking about?
- hinkley 3y ago
  We are perhaps not the best group on the internet for discussing biomechanics...
- rhn_mk1 3y ago
  If you're clipped in, why would you keep feet from sliding? Preventing sliding by pushing is how effort is wasted and is a possible explanation why a cyclist might feel much stronger when clipped in and no longer has to push - while attributing the lower effort to the upstroke pull.
stouset 3y ago
> Those are not necessarily examples of lifting. They are, and this is trivially demonstrable by literally just trying it on a bike. Seriously. Go put a road bike in the highest gear and try to get up to speed from a standstill. Not only will you be pulling up on the rear pedal, but you’ll be using your arms to try and wrench the handlebars off the stem too. Go climb a steep hill. Same thing occurs. It’s not like this is subtle. The contribution of your rear leg very clearly contracting will be impossible to miss.

jeffbee 3y ago

We have a large amount of power meter data demonstrating that elite and pro cyclists do not, in fact, exert much force on the rising stroke when in the saddle. They maintain a net downward force on the pedal most of the time. The benefit of clipless pedals is repeatable positioning and the ability to start the downstroke right at top dead center, without slipping off the pedal. The benefit is not from powering the backstroke.

hinkley 3y ago
Personally outside of dramatic moments like the Big Hill or the club smartass trying to drop everyone for giggles, driving through the bottom of the stroke was the only thing that felt like it 1) mattered and 2) could be sustained. But I think you have to go to triathletes to really see that effect more pronounced. Since they like to sit tilted a couple degrees farther forward on the bike, the hamstring is more accessible. At the end of the day a pro is 5-10% better than a serious cyclist at five different things. Even before you get to diet and genetics (and doping, sorry) they’re already outputting more watts and getting more of them to the wheels than I could hope to. Technique adds up.
stouset 3y ago
Yet cycling events are frequently won out of the saddle on the slopes or out of the saddle in the sprint. And yes, sometimes they’re won by someone time trialing away from the pack while in the saddle. But even then, most of the time it’s a breakaway pack which fights for the podium in an all-out sprint.
- hinkley 3y ago
  The breakaway pack also typically sprints away from the peloton. Because drafting is 30% easier than riding at the front. If you don’t catch a wheel as it goes past, you’re dropped. I’m looking around at all this ”data that we have about pedal strokes” and nobody mentions sprinters or climbing specialists. If they don’t know it’s important they won’t test for it. Sounds like “science” being done by domain neophytes and called objective. What is interesting though is that one claimed that advanced amateurs have higher peak stroke torque than pros. Pros are spreading more power out over a larger arc of the circle. Now that could still be 130° of the stroke for all I know but that still sounds like circularizing to me. I also haven’t found anyone yet who says LeMond was wrong about driving through the bottom of the stroke, which is how I rode.

hinkley 3y ago

> but all four of your limbs are at maximum exertion getting the bike up to speed. Oh goodness yes. When you’re going full out it’s like you’re trying to wring water out of a steel towel. Pull up on left handlebar while using right arm to prevent oversteer. Another fun failure mode is when you don’t quite trust your handlebars. I’m either not going to pull on these or I’m gonna stop before the Big Hill to find an Allen wrench and tighten these stupid things. I think the new design is meant to prevent a lot of that.

stouset 3y ago
> trying to wring water out of a steel towel I’m stealing this! Spot on.

jdietrich 3y ago

>the contribution of the lifting leg is crucial to getting up to speed This might feel true, but it isn't. Buy or borrow a dual-sensing power meter (Garmin Rally, SRM X-Power etc) and you can see for yourself - there's practically no useful power in the upstroke. Toe clips or clipless pedals can extend the power stroke, but only by a few degrees at the bottom of the stroke. https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-upstroke-2 https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-up... The intuition of cyclists is a very bad indicator of actual performance. For decades people thought that hard, narrow tyres were faster, but nobody had actually tested it properly. Narrow tyres have lower rolling resistance on a smooth steel drum in a test lab, but they have much higher rolling resistance on real roads with bumps and ruts. When paired with suitable rims, the reduction in rolling resistance of wider tyres more than compensates for the penalty of increased weight and drag.

ordu 3y ago
My cyclist's intuition says that leg clipping allows you to extort greater force on a down stroke. Without clipping the force is limited by your body weight, with it the only limit is your muscles. Thinking about it your hands and a back leg allow you to apply a lot of downward force to your body and your lead leg can add all this force to a stroke. It doesn't matter that your hands or back leg individually are not so strong when pulling, because their efforts are combined. In situations when you need not to extend as much force as you can, probably clips do not add much, though I do not know. I tried at some point to ride a bicycle without clips and nearly failed. My back leg tries to pull and leave a pedal. > https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-upstroke-2 https://bythlon-pedal.myshopify.com/pages/the-myth-of-the-up... They are saying that with high rpm cyclists do not pull. I can believe that, high rpm is beneficial exactly because you need to apply a relatively small force.
stouset 3y ago
I strongly encourage you to actually test this yourself. Having personally done so myself, all I can say is that you will be surprised. Time yourself on a max-effort sprint in a high gear from a standstill. Don’t pull up on half your efforts. Pull up on half your efforts. The effect isn’t subtle. I’m not particularly convinced by power meters not showing much here. The biggest reason being that pulling up has the effect of allowing you to push even harder down. Without pulling on the handlebars or pulling up on the rear pedal, the maximum force you can exert on the pedal is a function limited by your weight. By pulling up on those three points, your ability to push down harder is significantly greater. Another simple counterexample is hills. There exist hills in my city that are physically impossible to climb without clipless pedals. You can stand on the pedal all you want, but your body weight is not enough to overcome the downward pull from the slope. On clipless pedals, while pulling up, you can climb the hill.