Effect of the dominant side of hand, throwing, and hitting movements on trunk rotation muscle strength

Abstract

Asymmetries in trunk rotation muscle strength can be seen in trunk rotation movements in many sports performance. This present study aimed to investigate the effects of the dominant hand side, throwing and hitting movements on trunk rotational muscle strength with 36 healthy young male subjects, all of whom had played baseball beyond a recreational level. After identifying the dominant hand side for each subject, trunk rotational muscle strength was measured on both left and right sides to compare the dominant side to the non-dominant side for each subject. The results showed that the trunk rotation muscle strength was significantly greater on the non-dominant hand side. These results suggest that the asymmetry of individual former habitual movement experiences might still develop the asymmetry of trunk rotation muscle strength, related to throwing and hitting movements. Another possible mechanism for this might be associated with the neuromuscular control of movement in the non-dominant side trunk rotation, which was on the front side while swinging a baseball bat as well as throwing the ball.