Broctoon

This part at least is true... for those who have not learned how to do a track stand. Everything else in Dvdvija's post is up for debate (as has been happening throughout this long thread). But I think we can all agree that it's usually important to unclip when stopping.

genejockey 

Doubling you power is indeed silly talk. The 'pushing down' muscles are WAY stronger, what with having to oppose gravity and all.

Worth noting, however, in the 'power circle' that Kapusta posted above, that power comes on before TDC and continues past BDC. Not so much "pulling up", of course. More pulling through.

Dvdvija

Hey, how do you figure foot pulling is a myth? Have you tried?

StanJF

Actual studies, not anecdotal arguments, show an improvement in power of 15%-30% for road cyclists and 10% for Mountainbikers using clipless pedals vs flat. It’s most significant in sprints and to a lesser extent on hills. When I said double power (+50%), it was based only on my own experience. The reports are on the web. Data doesn’t lie, only people do.

WhyFi

I just don't know where to start, so I won't bother. Yikes.

genejockey 

How about "+50% isn't doubling"?

WhyFi

J28

Clips allow you to pull up as well as push down which is why they are associated with racing and speed. They allow you to control the pedal position when leaning into a turn. They do prevent slipping off the pedaI. I have always found them much more comfortable than riding unclipped. They look cool. Ordinary pedals look...ordinary.

Broctoon

I feel like we had a whole discussion about this and came to more or less of an agreement, and now some late comers are chiming in without even having read previous posts. Anyone else get that vibe?

J28

Some of us are new to this forum.

stephr1

Not to be a smart ass...well, OK, yes I will....

I prefer to retain my feet. Makes it tough to ride without them (not sure the end of my leg would get along very well with the pedal

genejockey 

(I made that joke two days ago)

stephr1

I guess great Bay Area minds think alike. I never saw yours but am happy to cite you as a source for my material

Cheers....

StanJF

My own experience was more than double power which is more than 50% (+50%). Sheesh. Sensitive.

gregf83 

Please share a study showing the effects of clipless pedals while sprinting. And then explain why track riders are both clipped and strapped in.

PeteHski

Okay let's go through this again one more time. Here is a summary by Dr Andrew Coggan in Training & Racing with a Power Meter (a very credible and reliable source)

"Elite cyclists actually pull up on each upstroke less than non-elite cyclists. Instead of pulling up on the pedals, elite cyclists minimise the power absorbed on the upward stroke (1)"

"Riders who deliberately pull up on the pedal stroke actually use more energy and are less efficient (2)"

"Deliberately modifying your pedal stroke to emphasise pulling up reduces your metabolic efficiency (3)"

References taken from the Journal of Sports Sciences and Medicine & Science in Sports and Excercise:-

1. Coyle, "Physiological and Biomechanical Factors Associated with Elite Endurance-Cycling Performance (1991)
2. Edwards, "Whole Body Efficiency is Negatively Correlated with Minimum Torque per Duty Cycle in Trained Cyclists (2009)
3. Korff, "Effect of Pedaling Technique on Mechanical Effectiveness and Efficiency in Cyclists" (2007)

I also posted quite a few links earlier in this thread. Here's one of them again in case you missed it.

https://www.cyclefit.co.uk/journal/c...ling-technique

A quick summary of the above link:-

"The research says we don’t (pull up on the pedals) – Dr Jeff Broker has done extensive pedalling kinesiology tests on 100 elite and professional cyclists over 10 years and his data shows that not one of them produces a meaningful upstroke."

"You will see that even elites and pros have a negative loading on the pedal during the ‘upstream’ or recovery phase of the pedalling circle. That is to say that even they don’t produce enough force at the pedal to offset the effect of gravity on their uphill-moving leg!"

There are going to be a few edge cases e.g. standing start track sprints, very low cadence climbing in a big gear, where pulling up on the pedals might be of some benefit. Or you may be deliberately pulling up on your pedals because you think that's the most efficient way to pedal. But that's not what scientific studies have shown to be good practice.

I'm also going to clarify one more time that I personally think clipless pedals are great and have been using them since the mid 1980s for all my road riding. I only mentioned this "pulling-up myth" in the first place because of people inevitably claiming that it's a primary benefit and major power advantage over flat pedals. @StanJF deserves a special mention for stating that "data doesn't lie, only people do" after stating that pulling up on your pedals doubles your power output. You just couldn't make this stuff up. It's hilarious!

PeteHski

Funnily enough I haven't looked at track sprinters. I didn't think that was particularly relevant to road cycling. Now I'm sure a track sprinter hauling a massive gear from a standing start will push and pull for maximal attack, but once they get up to a normal cadence and maximal power (not maximal torque) they will not be push/pulling for the same reasons pro road racers don't or are unable to anyway. It's been proven that at high cadence and power it is virtually impossible to pull on the pedal upstroke. It's more a matter of minimising the power absorbed on the upstroke.

I'm not looking for edge cases here, I'm just trying to point out that pedal pulling is not really a fundamental advantage of clipless pedals. They have plenty of other advantages, which is why I use them. But power is not one of them. I wish I could double my power output by pulling as that would increase my sprint power to 2400W and my FTP would be pushing 600W. I'd be happy with that!

PeteHski

Yes I have tried. I do occasionally do single leg cadence drills (although I'm not convinced about their benefits) which always reminds me how weak our hip-flexors really are relative to glutes.
I go with the science and try to pedal smoothly without consciously pulling on the upstroke. I find pedalling at a slightly higher cadence than normal (like +10 rpm) and very high cadence drills are the most effective ways to develop a smoother pedal stroke. That and simply just riding a lot since I was about 5 years old. Which reminds me that Andrew Coggan does actually warn against trying to consciously "modify" your pedal stroke as it can be detrimental to your efficiency.

gregf83 

For many, sprinting is not an edge case and you can put out more power when sprinting clipped in. I've done the comparison myself on my normal route and there are numerous points in the ride where being clipped in results in more power. None of the studies you quoted dispute this.

PeteHski

I'm not going to dispute that either and I never intended to.
I wonder what actually limits your power on flat pedals when sprinting? Are you sure it's your upstroke power (do you get that resolution on your power data?) or simply the fact that you are fixed securely in a more optimum foot position on the pedal? All the studies I have read state or imply that it is impossible to pull up with a positive force on your pedals at a high cadence and power, even if you were trying to. So now it's your turn to show me the peer reviewed studies that demonstrate otherwise.

LarrySellerz

Studies are garbage, what do the pros and pro coaches say

Kapusta

What was that agreement?

You mean that Larry should not be hitting on some dude’s girlfriend?

gregf83 

I can feel it when sprinting up a steep hill. I pull up. I agree, and have confirmed for myself, that for steady state riding clips make no difference to power or efficiency. I haven't seen any studies that look at pedal mechanics while sprinting, they generally are looking at steady state type efforts. But even if you're properly unweighting the pedal while standing and sprinting it's not very comfortable if your feet aren't secured. I didn't notice a huge difference, but something like 100-200W extra when clipped in. Most noticeable going up a short steep hills which we usually see a number of on any given ride.

PeteHski

Most of the studies are with pros and pro coaches.
It's the forum talk that is full of garbage.

boomerbicyclist

I have three bikes, each with a different style pedal. My Colnago has Look clipless (which I am still trying to get used to), my Bianchi has toeclips, and my Bacchetta has Power Grips, which I find to be a nice sort-of halfway point between flats or toeclips and clipless.

If you're not familiar with them, they're a fairly wide (1" or thereabouts) reinforced canvas strap that you put one end on the front of a pedal & the other on the opposite side of the rear of the pedal, such that when you insert your foot it supplies torque, holding the foot to the pedal. I've used 'em for nearly twenty years, and have yet to fall as a result of their use. Also, you can pull on the upstroke with them if you like--I've found it makes a difference when climbing or sprinting--and they're way less expensive than clipless, because you can use any footwear you like.