Changes in strength over the course of a swim season could predispose the shoulder to strength imbalances and lead to injury.
To examine isometric shoulder internal- (IR) and external-rotator (ER) strength in high school swimmers over a 12-week competitive season.
Three 3 × 2 × 2 ANOVAs with repeated measures were used to determine significant main effects for IR, ER, and IR:ER strength ratio.
27 (14 female, 13 male) high school varsity swimmers.
Main Outcome Measures:
IR and ER strength during preseason, midseason, and postseason.
Significant increases in IR strength in both groups were revealed for all test sessions. ER strength significantly improved in both males and females from preseason to midseason and from preseason to postseason. IR:ER ratio revealed a significant increase from preseason to postseason.
Increases in IR strength without equal gains in ER strength were revealed and could contribute to future shoulder pathologies in competitive swimmers