Muscular Inefficiency and Possible Speeds of Walking

IN walking over a level surface, were there no muscular loss or imperfect elasticity in the ground, the only work to be done would be that required to start the body and limbs at the walking speed, which work might be recovered when stopping. Thus any energy expended in walking on the level is due either to work taken up by the ground, or lost by muscular inefficiency. (Air resistance may be neglected at walking speeds.)