Sounds like this is the same thing for running.
The main advantage of the clips is to keep your leg in contact with the pedal throughout the cycle and make sure the ball of your foot is optimally placed on the pedal. With a traditional pedal you have to keep some downward force on the pedal to create friction to avoid slipping off, so even when that leg is rising up, you can't completely unload the pedal. With clips you can completely unload the pedal.
Additionally, the goal isn't to double your power output. It is to be better than the other cyclist. Even by just a tiny bit.
I personally think that clipping the feet helps more with left right stability. Also, if you are pulling with one leg, you can potentially push more with the other. Normally you can only push as much as you weight, but with the other leg clipped you can push your weight plus the force you use to pull the other pedal.
On a bike, if you want to put up more power you have options to push harder or spin faster. If you had to push harder than your weight, you could always change your gears to rather spin faster.
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.
And not pressing doesn't shine any light on the force of lifting.
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
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?
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.
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.
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.
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.
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.
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.
I’m stealing this! Spot on.
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-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.
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-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.
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.
I would also say that as a former cyclist and bike mechanic, there were thresholds of pedal adjustment where your foot would stay on the pedal if you only applied downforce, but not sufficient for any other force. It was a common enough problem that there were articles written about it.
Early Look models had this problem, but not as substantially as most of their copycats. There’s a reason they had little competition for most of a decade. I think the Shimano MTB pedals (with the little countersunk cleats) sometime around 2nd Gen, were the first time Look got properly nervous.
There were some people for whom you had to dial the tension to the edge of “annoying” for clipping in in order to keep them from accidentally clipping out at speed or on hills, both if which can be dangerous.
Even when I had mine dialed in “right”, I ended up pulling one shoe vertically out of the pedal when I came to a stop without disengaging first. Adrenaline is a hell of a drug.
I know them as 'Tretkorb'. How do you call them, toe clips?
After about 20 years pause, only using an antique 'citybike' with three-spead gear hub and coaster brake.
It feels like I can fly again! :-)
I'd guess the highest power and torque outputs in cycling are from track sprinters. If you look at what they use it's both cleated pedals and straps.
No matter how they're generating that torque they definitely don't want to slip off a pedal going full tilt.
Riding a hardtail I always want clipless pedals because I don't want to have have my ankles at a weird angle just to grip pedals when I go over something rooty.
> When paired with suitable rims, the reduction in rolling resistance of wider tyres more than compensates for the penalty of increased weight and drag.
Unless you include specific conditions you can't really say that a hard, narrow tyre won't be faster with any confidence.
At some point having even wider tyres will only slow you down because the surface bumps don't get any bigger but the cda of your front tyre and rolling resistance due to hysteresis keep increasing.
e.g. a 4" fat bike tyre at 0.5bar is not going to be faster in a velodrome than a 23mm tub at 7bar just because they're wider. If you were riding on snow or cobblestones however...
Similarly there as a few different muscles that can bring your knee up if it’s pinned between your hip and a pedal. The hamstring being one of them. Though personally (as an enthusiast rather than a pro) I always felt like I had more stamina from just driving through the bottom of the stroke. I only pulled up on hills and when someone tried to drop us.
And yet Thai boxers appear to be able to generate at least as much force using upward knee strikes as push kicks.
Not necessarily :-)
See https://www.eurosport.com/cycling/famenne-ardenne-classic/20... for an example where that happened and the sprinter still won.
Well momentum can be your friend or your enemy.
It looks like not only did he pull his foot out, he also clipped his chain or front derailleur with his foot and popped himself down into the small chainring.
How do you explain the effect in OP’s device if this is “disproven”? Nobody seems to have offered an alternative theory.
I don't think I ever got around to trying one. I was the youngest regular member of our club. Power output was not my primary problem.
Anyway, I can't find any of these so-called studies that admits to knowing what a sprinter is let alone a green jersey, so I'm going to keep my eye out for less flawed studies.
In fact, get me one by a team medic or physiologist, and then we can talk. Until then it's nerds in coats coatsplaining things to people actually doing the work.