Effect of mental practice on isometric muscular strength

The purpose of this study was to see if mental practice (MP) would increase voluntary isometric muscle strength in normal individuals. Twenty-four female subjects were randomly assigned to either a control group or a MP group. The study was conducted over a four-day period using a pretest, posttest, and control group design. The MP group participated in four, 30-minute covert practice sessions. During these sessions, subjects were instructed to cognitively practice isometric contractions of their right quadriceps muscle. Surface electromyography was applied during each practice session to ensure that subjects were not physically contracting their muscles. The data were analyzed using a two-way analysis of variance with repeated measures on one of the factors. The results of this study showed that the MP group significantly (p < .05) increased (12.6%) their quadriceps muscle strength compared to the control group.