Effects of shoelace tightness on lower limb biomechanics and subjective perception during lateral shuffle in basketball.

Purpose: Shoelace tightness is an important factor that may influence basketball players' performance and injury risk during shuttle slip movement. This study aimed to examine the effects of shoelace tightness on shoelace tension, lower limb kinematics and kinetics, and subjective perception in basketball players. Methods: Sixteen male college basketball players performed lateral shuffle movements with their dominant foot landing on a force plate under three shoelace tightness conditions (loose, comfortable and tight). A motion capture system and a force plate were used to measure lower limb kinematics and kinetics, respectively. A customized wireless shoelace tension system was used to measure shoelace tension at three locations on the dorsum of the foot. Visual analogue scales were used to assess perceived comfort, foot pressure and in-shoe displacement. Results: Shoelace tension increased with shoelace tightness (loose: 13.56 ± 6.21 N, comfortable: 16.14 ± 5.35 N, tight: 21.25 ± 6.19 N) and varied with shoelace position (front: 20.19 ± 5.99 N, middle: 13.71 ± 5.59 N, rear: 17.04 ± 6.95 N). Shoelace tightness also affected some of the ankle joint kinematics and kinetics as well as the subjective ratings of foot pressure and in-shoe displacement ( p < 0.05). The loose shoelace increased the ankle inversion angle, while the comfortable shoelace decreased the knee negative power. The tight shoelace increased the perceived foot pressure and reduced the inshoe movement ( p < 0.05). Conclusions: Shoelace tightness could significantly affect lower limb biomechanics and subjective perception during lateral shuffle in basketball. Basketball footwear designers should consider the incorporation of multiple shoelaces or zonal lacing systems to allow athletes to fine-tune the tension across different areas of the foot.