Some factors modifying the expression of human strength

Abstract

The maximal pull of forearm flexors was increased and, in some instances, decreased in predictable fashion by a loud noise, by the subject's own outcry, by certain pharmacologic agents (alcohol, adrenaline, and amphetamine), and by hypnosis. Significant average changes ranging from +26.5% to –31% were observed. An analysis of these data and that of others leads us to regard all performances short of the maximum limit, which is always imposed by the structure and prevailing physiologic state of the performing muscles, to be manifestations of acquired inhibitions that in turn are subject to disinhibition by pure Pavlovian procedures, by anesthetization of inhibitory mechanisms, or by pharmacologically induced symptoms serving as stimuli for disinhibition. Submitted on June 20, 1960