Energetically optimal stride frequency in running: the effects of incline and decline

SUMMARY At a given running speed, humans strongly prefer to use a stride frequency near their ‘optimal’ stride frequency that minimizes metabolic cost. Although there is no definitive explanation for why an optimal stride frequency exists, elastic energy usage has been implicated. Because the possibility for elastic energy storage and return may be impaired on slopes, we investigated whether and how the optimal stride frequency changes during...