Context: Swimming requires well-balanced scapular-muscle performance. An additional strength-training program for the shoulders is pursued by swimmers, but whether these muscle-training programs need to be generic or specific for endurance or strength is unknown.
Objective: To evaluate isokinetic scapular-muscle performance in a population of adolescent swimmers and to compare the results of training programs designed for strength or muscle endurance.
Design: Controlled laboratory study.
Setting: University human research laboratory.
Patients or other participants: Eighteen adolescent swimmers.
Intervention(s): Each participant pursued a 12-week scapular-training program designed to improve either muscle strength or muscle endurance.
Main outcome measure(s): Bilateral peak force, fatigue index, and protraction/retraction strength ratios before and after the scapular-training program.
Results: Scapular protraction/retraction ratios were slightly higher than 1 (dominant side = 1.08, nondominant side = 1.25, P = .006). Side-to-side differences in retraction strength were apparent both before and after the training program (P = .03 and P = .05, respectively). After the training program, maximal protraction (P < .05) and retraction (P < .01) strength improved on the nondominant side. Peak force and fatigue index were not different between the training groups. The fatigue indexes for protraction on both sides (P < .05) and retraction on the nondominant side (P = .009) were higher after the training program.
Conclusions: We describe the scapular-muscle characteristics of a group of adolescent swimmers. Both muscle-strength and muscle-endurance programs improved absolute muscle strength. Neither of the strength programs had a positive effect on scapular-muscle endurance. Our results may be valuable for coaches and physiotherapists when they are designing exercise programs for swimmers.