Faster top running speeds are achieved with greater ground forces not more rapid leg movements.

@article{Weyand2000FasterTR,
  title={Faster top running speeds are achieved with greater ground forces not more rapid leg movements.},
  author={Peter G. Weyand and Deborah B. Sternlight and Matthew J Bellizzi and Seth Wright},
  journal={Journal of applied physiology},
  year={2000},
  volume={89 5},
  pages={
          1991-9
        }
}
We twice tested the hypothesis that top running speeds are determined by the amount of force applied to the ground rather than how rapidly limbs are repositioned in the air. First, we compared the mechanics of 33 subjects of different sprinting abilities running at their top speeds on a level treadmill. Second, we compared the mechanics of declined (-6 degrees ) and inclined (+9 degrees ) top-speed treadmill running in five subjects. For both tests, we used a treadmill-mounted force plate to… 
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