Speed dependant influence of attentional focusing instructions on force production and muscular activity during isokinetic elbow flexions

This experiment assessed the influence of internal (movement) or external (outcome) attentional focusing instructions on force production and muscular activity at different movement speeds. Twenty five participants completed 10 reps of single arm elbow flexions on an isokinetic dynamometer at speeds of 60°, 180° and 300° s−1 under three conditions (control trial, followed by counterbalanced internal and external focus trials). EMG activity of the biceps brachii and net joint elbow flexor torque were measured. An external focus was associated with significantly lower EMG at all speeds when compared to an internal focus. However, an external focus resulted in greater torque production only at 60° s−1 when compared to an internal focus. These findings suggest that movement speed may influence the efficacy of different attentional focusing instructions, with implications for the instruction of movements in sport, exercise and rehabilitation settings.