REVERSAL OF ANTAGONISTS - EFFECT ON ELBOW EXTENSION STRENGTH AND ENDURANCE

Objective: To evaluate the reversal of elbow antagonists designed to f acilitate the extensors relative to agonist-only contractions of the e xtensors, while using a protocol previously demonstrated to result in an increase in strength through motor learning. Design: Two-group conv enience sample composed of healthy subjects. Setting: Clinic research laboratory. Subjects: Twenty-eight healthy women without a history of upper extremity injury or neurologic disorder. Measurements: Elbow ext ension strength and endurance were measured during maximal effort isom etric reversal of the elbow antagonists (experimental group) and elbow extension only (control group) resistance exercise. Biceps brachii sh ort head (BBS), triceps brachii lateral head (TLAT), and triceps brach ii long head (TLNG) electromyographic (EMG) activity was measured conc urrently. Results: There were no significant differences between group s for either elbow extension strength, BBS, TLAT, or TLNG EMG activity . The experimental and control groups exhibited a significant linear ( p < .01) and quadratic (p < .01) increase in baseline strength of 5.2N .m (30.5%). EMG activity from each muscle group increased linearly (p < .01) across all rest sessions, Similar results were observed for elb ow extension strength and biceps and triceps EMG activity during fatig ue testing. Conclusions: The reversal of antagonists technique was not superior to agonist-only resistance exercise, nor did it interfere wi th the acquisition of muscular strength or endurance through motor lea rning. (C) 1997 by the American Congress of Rehabilitation Medicine an d the American Academy of Physical Medicine and Rehabilitation.