Foot speed, foot-strike and footwear: linking gait mechanics and running ground reaction forces.
Running performance, energy requirements and musculoskeletal stresses are directly related to the action-reaction forces between the limb and the ground. For human runners, the force-time patterns from individual footfalls can vary considerably across speed, foot-strike and footwear conditions. Here, we used four human footfalls with distinctly different vertical force-time waveform patterns to evaluate whether a basic mechanical model might explain all of them. Our model partitions the body's total mass (1.0 Mb) into two invariant mass fractions (lower limb=0.08, remaining body mass=0.92) and allows the instantaneous collisional velocities of the former to vary. The best fits achieved (R(2) range=0.95-0.98, mean=0.97 ± 0.01) indicate that the model is capable of accounting for nearly all of the variability observed in the four waveform types tested: barefoot jog, rear-foot strike run, fore-foot strike run and fore-foot strike sprint. We conclude that different running ground reaction force-time patterns may have the same mechanical basis.
['Clark|Kenneth P|KP|', 'Ryan|Laurence J|LJ|', 'Weyand|Peter G|PG|']
D001696:Biomechanical Phenomena D005528:Foot D005684:Gait D006801:Humans D035002:Lower Extremity D008962:Models, Theoretical D012420:Running D012775:Shoes
Running performance Barefoot running Biomechanics Force-motion