For a long time I've heard coaches instruct cyclists on the efficiency of keeping your foot level throughout the pedal stroke. For those of you that know me, you know that I rarely accept anything just because someone else says it, and recently this has been on my mind. The more I think about this concept of keeping your foot level throughout the pedal stroke the more it just simply doesn't make any sense.
First, let's think about the pedal stroke for a minute. Basically what you have is a device that can rotate attached to an arm that is attached to a sprocket. I just described a crank set with a pedal for those of you not following. As you push, pull and ideally move that pedal around the circle it turns the sprocket and because of the chain attached to another sprocket on your wheel, you move forward. What makes the pedal stroke slightly more complicated than simply turning the crank is a factor of being attached at a point that is not directly under your own "arm," which in this case is actually your leg.
I found this 3D animation of how a steam engine uses the same process to turn it's wheels as a cyclist does their cranks. Pay attention to the rear wheel.
This is exactly what your pedal stroke would look like if we attached ourselves to the pedals at the ankle. However, we don't. Cleats are generally placed pretty close to the ball of your foot so this adds another pivot point, your ankle, to the equation. If you think of the rod connected to the rear wheel in the video as a very long foot, then the other end, connected to another rod can be thought of as acting as an ankle. Clearly there is a some vertical motion necessary to move the rod or foot around the circle.
The power of you pedal stroke comes from various muscle groups, but none of which are really located in your foot. Your foot is simply the connecting point and transfer of that power to the pedal. Because of this, it doesn't make sense to restrict your foot from being able to move vertically through the circle. It's no question that the closer to an actual circle you pedal the more efficient your stroke. But why does pedaling a circle require a flat foot?
I believe there are two places that it makes the most sense for your foot to be flat in the pedal stroke. Thinking of the pedal stroke as a clock, I think those two points are 3 and 6 o'clock. The only reason I think they should be flat here is because I think these are the two places where your foot would pass through a flat stage in order to continue to deliver the most power to the pedals. At 3 your foot would be leveling as it pushes down and at 6 o'clock it'd pass through level as your heel raises to start to pull.
People have always described the bottom, 6 o'clock as the place where you should "scrap the bubble gum off of the bottom of your shoe." This analogy is great for getting someone to initiate the upstroke required to pedal a full circle, however, it's also impossible to do this both literally and figuratively with a flat foot. Next time you step in gum or dog crap, try scrapping it off your shoe without at least slightly lifting your heel. See how well that works out. I think it's also obvious that if we want to begin to move a point in a vertical fashion and the point can pivot, it makes sense that we'd lift it from a higher point. Nobody picks up a box by laying down next to it and levitating. We pick it up by applying force at a point higher than that in which we make contact. The same physical properties apply to a pedal stroke.
I've also read that the biggest dead spot, meaning we aren't applying direct force, in a pedal stroke isn't the back side where it's assumed that leg takes a break and is simply lifted by the other leg pressing down, but actually at the top between 12 and 2 o'clock because this point requires pushing forward. It would make sense to me that through this place, where you'd generally get yelled at for having anything but a horizontal foot, your heel can be tilted higher than the pedal to help push through and then rotate below the pedal to continue to push to 6.
It's been suggested that if you look at most pro riders they all have level feet throughout the pedal stroke. So, I have been looking at their pedal strokes in both pictures and video and have found the exact opposite to be true. I don't think anyone has a level foot as they pedal because I think your body, as a mechanism that wants to be efficient because it's always trying to save energy, naturally starts to figure out the best way to move your feet around that circle repeatedly. Feel free to youtube or watch the current Giro coverage on Universal Sports and see for yourself.
I guess through all of this pondering it brings me back to the original question of why are coaches constantly telling their athletes to keep their feet level? My only assumption is that it's more of a process of planting a seed so that the cyclist is aware of the pedal stroke. In the base portion of a training plan and even on recovery rides it's valuable to do pedaling technique drills to enforce good habits of muscle memory for later when you're suffering like a dog trying to stay on that wheel. While I am against the idea of forcing your foot to stay level foot during the 360 degree rotation of the pedal stroke, I am also against drastic examples of heels up or down. I'm not saying that when you go through 12 o'clock your heel should be so vertical that your leg, foot and crank arm are all a straight line. That extra effort of motion to get your foot in that position would be an obvious waste of energy and zap efficiency. I don't know what degree range I'd like to see from people. I think in most cases your body figures it out and if I or anybody else looks at your foot and doesn't immediately marvel at the ridiculousness of it, you're probably fine.
I wish I had a lab where I could set up a machine and test a bunch of variables with a fixed axle to simulate keeping your foot level and one that is free to move in what I theorize as more efficient. However, I don't. I also don't have fancy illustrations to show or a lot of videos. This is really just my own hypothesis about something that has never made much sense to me. I welcome any and all comments that may feel I'm totally off.
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