Injury prevention

Document Type



This study compared time-varying measures of trunk muscle activation and lateral flexion between planned (PSS) and unplanned sidesteps (UPSS) in seven male participants. Fine-wire and surface electromyography signals from nine muscles characterised trunk muscle activation. Greater trunk activation was observed in UPSS during the penultimate stance and action-stance, but not during flight phase preceding the action-stance. Significant differences were observed in flight phase trunk lateral flexion angle between tasks. No differences were found in lateral contraction ratios between movement conditions. These preliminary results indicate that trunk muscle activation differences between PSS and UPSS are not sufficient to account for the increased lateral forces experienced during UPSS. Thereby, resulting in the higher trunk lateral flexion observed during UPSS.