This is the thread that Berkeley Mike was referring to. It's worth a quick read through:Berkeley Mike said:There has been an extensive discussion about this issue in the Passion forum very recently.
However I have imported a graph that I thought was really interesting describing the muscle groups that provide power in certain parts of the pedal stroke. I have no idea how accurate it is and it certainly is not gospel. However, it fits the way I think about peddling.
One thing to consider with flat pedals when compared to clipless pedals is that your foot isn't restricted to one position. With clipless pedals a typical MTB shoe and clipless pedal design means that you pedal using the ball of your foot.
Using a flat pedal your foot can choose its own natural position on the pedal. You'll often end up pedalling using the midfoot instead of the ball of the foot. There's been quite a bit of discussion over the last few years as to whether pedalling using the midfoot can be better than pedalling using the ball of the foot, both in terms of improved torque but also for reducing injuries.
(see posts by "Biomac" and "Steve Hogg" in particular)
"Though unusual, the idea behind Heine's mid-foot or 'arch' cleat position is logical. He and other mid-foot proponents such as renowned coach Joe Friel and Cyclingnews fitness panelist Steve Hogg surmise that the majority of a rider's power is produced by the quadriceps, glutes and hamstrings while the lower leg only serves to stabilise the efforts of what happens above. As such, the lower leg is merely a conduit and doesn't produce enough effective power to justify the metabolic cost.
Moving the cleats back to the arch - a location Heine defines as optimal - thus substantially reduces the workload on the calves and leaves more oxygen and energy remaining for those larger muscle groups to produce more total power before fatigue and exhaustion can set in. In other words, you can go faster for longer with no additional training required aside from adjusting to the new position.
"Compare it to doing push-ups," says Heine. "One time on your fingertips, second time on the palms of your hands. Total [lactic acid production and oxygen consumption] will be equal but the fingertip exercise will exhaust you sooner."
Interesting enough, but does it work? The mid-foot cleat position feels weird at first but it only took a couple of rides to adapt and dare we admit it, we actually like it - at least most of the time. Most mountain bike riders on platform pedals naturally adopt this position already.
With the relatively flexible lower leg system taken out of the equation, power transmission is noticeably more direct and the power stroke is effectively lengthened. As promised, almost all stress on the calves is relieved - virtually eliminating cramps there - and we really did find ourselves motoring along on flats and extended climbs better than usual. Bikeradar.com
It's something to think about.
Pictured below: Biomac midfoot cleat position is very close to the midfoot position your foot can end up in naturally when pedalling on flat pedals.
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