I train runners to run more efficiently, in part by reducing their vertical oscillation (bounce), but I don't know how to figure out how much work they do during a marathon based on the size of their oscillation and their weight. I also want to be able to tell them how much falling force they have to cope with.(adsbygoogle = window.adsbygoogle || []).push({});

I have a runner who weighs 130 lbs. He moves up 3" and down 3" with each stride he takes. During a marathon, he takes 26,200 strides. How do I compute how much work he does during a marathon pushing his body weight up? How much work would he do if he cut his bounce to just one inch? To 1/2"?

At the height of his oscillation (usually when he toes off his rear leg) he then falls back down to earth. How much force does he land with? Years ago I read that with a 2" bounce, a runner lands with 4X his body weight, 3" bounce = 6X body weight and 4" bounce = 8X body wieght. Are these numbers correct?

Thank you in advance for any help you can offer.

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# Homework Help: Work done during running

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