ENERGETCS OF BIPEDAL RUNNING 1. METABOLIC COST OF GENERATING FORCE Similarly sized bipeds and quadrupeds use nearly the same amount of metabolic energy to run, despite dramatic differences in morphology and running mechanics. It has been shown that the rate of metabolic energy use in quadrupedal runners and bipedal hoppers can be predicted from just body weight and time available to generate force as indicated by the foot ground contact. We tested whether this link between running mechanics and energetics also applied to running bipeds. We measured rates of energy consumption and times of foot contact for humans (mean body mass 78.88kg) and five