The Effect of Corrective Exercises on Ground Reaction Forces in Male Students With Upper Crossed Syndrome During Throwing

Purpose: Poor posture has a negative impact on physical capability and is associated with changes in biomechanics and motor control. The purpose of this study was to assess the effect of corrective exercises on ground reaction forces (GRFs) in male student handball players with upper crossed syndrome (UCS) during throwing.

Methods: Thirty male handball students with UCS participated in this single-blind randomized controlled trial (IRCT20200622047888N2; IR.HUMS.REC.1402.135). Fifteen received an 8-week corrective exercise intervention (exercise-intervention group [EG]), consisting of exercise targeting muscles involved in the UCS, and 15 served as the control group (CG). During handball throwing, GRF was measured by force plate. The forward head and rounded shoulder angles were measured with a photogrammetric method. All measurements were repeated 8 weeks later.

Results: Significant interactions for virtually all parameters indicated that changes over 8 weeks differed between the CG and EG. A reduction in GRFs and a delayed occurrence of peak GRFs were observed in the EG, but not in the CG (P < .05). This was accompanied by a significant reduction in forward head (P < .03; effect size: 0.87; 95% confidence interval, -2.34 to 0.13), rounded shoulder (P < .05; effect size: 0.68; 95% confidence interval, 0.32 to 1.22) and thoracic kyphosis (P < .02; effect size: 0.64; 95% confidence interval, 0.54 to 1.25) angles in the EG (P < .05) with no significant change over 8 weeks in the CG.

Conclusion: Corrective exercises targeting muscles directly involved in UCS induces functional and postural improvements in male student handball players with UCS.