This study aims to investigate sex differences in knee biomechanics during unexpected cutting and their correlation with sensorimotor function. Sixteen male and 16 female athletes were recruited. Participants were asked to complete six unexpected cutting tasks on their dominant side. Peak muscle force, position sense, and force sense of the dominant knee were measured using a CON-TREX isokinetic dynamometer. Results suggested that female athletes demonstrated a higher knee valgus angle at initial contact (p = 0.004) and peak knee valgus angle (p = 0.027) than males. Females also had a lower peak knee flexion angle (p = 0.001) and knee flexion moment (p = 0.002) than males. Quadriceps force sense errors were correlated with peak knee valgus angle in female (r = 0.558, p = 0.025) and male (r = 0.550, p = 0.027) athletes. In addition, in female athletes, higher quadriceps strength was related to a greater peak knee flexion angle (r = 0.525, p = 0.037). In summary, female athletes exhibit knee biomechanical characteristics associated with a higher risk of anterior cruciate ligament injury compared with male athletes. Insufficient quadriceps strength and larger force sense error are associated with the knee biomechanical characteristics.
This study examined how different hand positions influence key biomechanical characteristics of elbow joint loading and performance during the forward handspring. Nine adolescent male gymnasts performed five trials using parallel (PHP) and outward (OHP) hand positions. Kinematic and kinetic data were collected using eight infrared cameras (250 Hz) and two force plates (1,000 Hz), with analysis conducted on the arm in contact with the force plate. The OHP produced greater maximum vertical and resultant ground reaction forces and net vertical impulse than the PHP, while exhibiting a shorter contact time. As a result, vertical velocity at take-off, change in centre of mass height, and flight time increased, indicating mechanical characteristics favourable for forward handspring performance. Meanwhile, the OHP exhibited greater elbow adduction moments, suggesting higher elbow joint loading. In contrast, the PHP attenuated elbow joint loading through greater flexion and internal rotation, facilitating shock absorption and propulsion over a longer contact time. This was reflected in greater negative and positive elbow joint work in the PHP than in the OHP, despite similar net joint work. These findings suggest that hand position selection may involve a balance between performance and elbow joint loading, highlighting its importance during the forward handspring.
