The Shoe, Pedal, Cleat Connection — A Circular Relationship
Over the course of human evolution the body’s made dramatic adaptations as we’ve evolved from creatures that rarely stood upright to ones who nearly always stand that way. Much of that adaptation is in the foot. Most of these changes help us walk and run. Around 87% of us have a varus foot. That is, as we stride forward the foot strikes on its outer edge. Then as the body moves over the foot in its forward motion we roll toward the inner edge. As we continue the stride we roll off the big toe. At the same time as the foot rolls from outside to inside the arch collapses, absorbing energy, then, as the weight moves toward the other foot it opens back up, releasing that stored energy. Essentially the foot acts as a spring. It cushions the knee, hips, and spine as well as itself. All that works great for walking and running, it’s worse than useless on a bike.
Yet the feet are the only place we are mechanically attached to the bike. The foot/shoe/pedal interface is the only way we transmit our power directly to the machine. So, it seems, any rider seeking optimum power would pay close attention to his or her feet and shoes. But how many times have you heard riders complain about pain in their feet, knees and or hips? Complain about lacking power even though they just had a bike fit? How about the times you’ve watched someone’s knees, maybe your own, making weird patterns side to side as they, or you, pedal?
On the bike when your leg rises on the backstroke there is no weight on the foot so the arch fully opens. Then, as you kick forward and weight the foot, the arch collapses.
Since bio-mechanically our bodies strive for a straight line from knee through ankle the knee tracks the arch. That is, as the knee comes up on the backstroke it moves outward as the arch opens then inward as it collapses. All the while the heel mirrors the knee which is where pedal float comes into play. Not only does such movement rob you of power but can lead to knee pain or worse for those who try and override it. Your shoe fit should keep you tracking in a flat plane, not your conscious effort.
While this is a complex challenge let’s look at the three major components of a well set-up foot/shoe/pedal interface: Shoe fit, arch support with varus correction, and cleat position.
Most bike shoes are neutral in relation to the pedal. They make no allowance for the foot’s tendency for a varus movement. Usually the shoe comes with a paper-thin insole as well, offering no support for the arch and, thus, allowing significant collapse of that arch in the power producing downstroke.
Bike shoes are made with a rigid sole, the better for power transfer. Nearly all modern shoes have distinct curves which roughly match the foot, at least the shoe is deeper where the ball of the foot, the metatarsal heads, rest.
It’s logical one should buy a shoe that fits closely so the metatarsals fit into that spot built for them. Unfortunately many riders buy a shoe that’s too big as they feel the correct size shoe is too small side-to-side. Usually they simply need more arch support. Their arch collapses as they stand on it and impart that feeling of shoe tightness.
Assume we need no more than a little fingers width between the longest toe on your largest foot and the end of the shoe. If you can wiggle your toes freely with that fit you are good.
Arch support with varus correction.
So, what can you do if the shoe you favor has a poor insole and you, like the great majority of us have a varus foot? Change the insole and add either internal or external varus correction.
You must use a cycling specific insole as those of a more general design correct the rear two thirds of the arch while cycling is a forefoot exercise. Good cycling specific insoles emphasize the forward portion of the arch. Various companies make these insoles. They range from ones you pop in the shoe without modification to fully customized versions. Most of the non-modifiable ones come in a range of different arch supports, allowing you the option of less or more support and accommodating different arches; those that are flatter and/or more rigid to those with high, supple arches.
You must try the different versions while on your trainer-mounted bike. Don’t settle for the pair that feels OK while you simply stand in them!
As you pedal under a reasonable load, say 60%, watch your knees (in a mirror if possible). Do they move in a straight line relative to the top tube? Are they equidistant from that top tube? If yes on both counts you’re set. However, if one or both of these are still problems you need further correction.
Often that is varus correction. Different companies make canted inshoe wedges which offer, usually, about 1.5 degrees of cant. That gives you the equivalent of about 4 degrees of forefoot cant, the nominative amount in our species.
Stick one under the insole of both shoes unless one of your legs tracked dead straight. The thicker side is toward the big toe and is at the front of the shoe. Try it on the bike. Do you see a difference? Experiment until you have a smooth spin with both legs tracking uniformly distant from the top tube with no discernable side-to-side knee movement. You should have very little or no side-to-side heel movement as well.
Never use more than two wedges inside the shoe. If you need more, use one of the various under cleat types available. Those tilt the whole foot while the under insole ones primarily tilt the forefoot.
Finally, but perhaps most importantly, cleat position.
Recent research suggests proper cleat orientation locates the center line of the cleat roughly equal to the center of the third metatarsal. Doing so produces some important benefits including more power, better use of the muscles of the foot and leg and greater comfort.
Set the lateral adjustment so that as close as possible you have hips over knees, over ankles
We produce more power not by stomping down on the pedal but by kicking over the top of the stroke, thus applying more force to a greater segment of the chain ring. Think of a weight on the end of a string. If you rotate your wrist outward as you spin the weight over your head centrifugal force contributes to a good, round circle. If you yank down on the string, however, it simply falls.
Since as you pedal over the top of the stroke you are in effect pushing forward, you need the cleat behind the center line of the pedal spindle. Otherwise you have the interesting task of pushing from in front.
As well, if we locate the cleat further back on the shoe we reduce the demands on the fine muscles of the foot and lower leg as there is less call for utilizing those in simply maintaining balance.
Finally, with less pressure on the ball of the foot we increase comfort.
As limitations on space here prevent a real in-depth discussion of shoe/foot issues let me leave you with the thought that you can solve numerous problems with proper support and proper placement. Generally the approach suggested in this article will lead to a smooth, powerful pedal stroke and years of injury-free riding. If you follow the advice and you end up with any new pains you did not have before, immediately undo the adjustments and talk to your coach. If you cannot resolve your particular issues on your own, consult a fit specialist. This holds true as well for those few with a neutral foot or a valgus foot. The fit specialist may further suggest someone trained in producing custom orthotics. Rest assured, however, you can ride with more power and comfort with just a bit of work.
Associate Coach John Forbes coaches all levels of road and track racers and triathletes, and particularly enjoys working with master age athletes. He is a professional bike fitter in Portland, Oregon.
Thanks for posting, John; this is useful information.