Effects of Clubbell and Stepbox Training on Range of Motion, Isometric Rotation Strength, and Stability of Shoulder in Badminton Club Members

This study was designed to examine the effects of a 12-week clubbell-stepbox training on range of motion (ROM), isometric rotation strength, and stability of shoulder in badminton club members. Thirty male participants, aged 20-30s and grade A badminton club members, were randomly assigned to either a training group (TR: n=15) or a control group (CON: n=15). The TR performed a circuit training 3 sessions/wk and 50–55 min/session, combining clubbell exercises (maximum 8–12 reps) and stepbox exercises (at ≥77% of HRmax) for 12 weeks, whereas CON maintained their usual lifestyle without any interventions. Dependent variables including ROM, isometric rotation strength, and stability of shoulder were measured, and a two-way repeated measures ANOVA was conducted to analyze the effects of the intervention. Regarding shoulder ROM, flexion (non-dominant side: ND), external rotation (dominant side: D), and total rotation (D) increased significantly in the TR. Regarding isometric rotation strength, internal rotation (D and ND) increased significantly in the TR, while external/internal rotator ratio (ND) decreased significantly. Regarding stability, both groups showed a significant increase in closed kinetic chain upper extremity stability test (CKUEST), but TR showed a larger increase. It was concluded that the 12-week clubbell-stepbox training had positive effects on ROM and stability of shoulder in male badminton club members aged 20-30s. However, it had a negative effect on isometric rotation strength. Therefore, future studies would be warranted to explore training methods that maintain a balance between external and internal rotation strength.