Effects of footwear collar height on lower-limb biomechanics during running and change-of-direction tasks in court-sport athletes.

Collar height is a distinctive feature of court-sport footwear, yet its biomechanical effects remain underexplored. This study compared the effect of low-cut and high-cut footwear on lower-limb biomechanics during straight-line running and change-of-direction tasks in court-sport athletes (11 females, 11 males). During straight-line running, reduced ankle dorsiflexion (32-77% of gait cycle, mean difference [MD]: 2.6°) and toe-out angles (46-76%, MD: 2°), and increased knee abduction angles (14-20%, MD: 0.9°) were observed in high-cut footwear. During the change-of-direction task, reduced ankle dorsiflexion (28-64%, MD: 2.8°) and rearfoot inversion angles (72-87%, MD: 2.6°) were observed in high-cut footwear. Independent of collar height, female participants exhibited greater knee abduction angles during running (79-100%, MD: 5°), while they exhibited smaller knee flexion (38-49%, MD: 7.3°; and, 65-82%, MD: 9.6°), hip abduction angles (36-97%, MD: 8.6°), reduced knee extension moments (54-82%, MD: 0.8 Nm/kg), and greater hip abduction moments (33-40%, MD: 0.9 Nm/kg) during the change-of-direction task. Overall, our findings indicate that low-cut footwear allowed greater ankle mobility, while high-cut designs limited rearfoot inversion during lateral movements. Hip and knee biomechanics were similar across collar heights, but sex-based differences existed. Footwear collar selection should reflect common playing demands and individual biomechanics.