Flexion and extension forces generated by wrist-dedicated muscles over the range of motion

An experiment was performed to evaluate the relationships among active range of motion (ROM), gender, wrist position and direction of force exertion in their effects on the magnitude of static force exerted by the wrist-dedicated muscles in wrist flexion and extension. This study employed 60 right-hand-dominant subjects (30 male, 30 female) between 20 and 30 years of age, all reporting no prior wrist injury and good to excellent overall physical condition. The ROM of each subject was used to determine the number of wrist positions evaluated for static maximal voluntary forces generated in wrist flexion and extension while they were instructed to relax their fingers; thus only the six wrist-dedicated muscles were employed in the exertion. The ANOVA procedure showed gender, wrist position, direction of force exertion, and the wrist position interaction with direction to have significant effects upon maximal force exertion. Females averaged 76.3% of the mean male flexion force and 72.4% for extension. On average, extension forces were found to be 83.4% of those generated by flexing the wrist-dedicated muscles.