Purpose The full‐body kinematic chain plays a crucial role in golf swings, and trunk muscle fatigue may significantly affect swing mechanics. This study aimed to investigate how trunk muscle fatigue influences trunk and lower limb kinematics during golf swings. Methods Eleven healthy adult golfers (mean age: 20.3 ± 0.8 years) participated in a pre–post experimental study conducted in a biomechanics laboratory with a grass‐simulated hitting surface. Participants performed golf swings with a 7‐iron before and after undergoing a trunk muscle fatigue protocol involving plank exercises. Three‐dimensional kinematic data of the trunk and lead‐side lower limbs were recorded. Results Following the fatigue protocol, trunk sagittal plane stability significantly decreased (pre: 47.9°, post: 43.4°, p < 0.01). Ankle range of motion also declined in both the sagittal plane (34.5° to 30.0°, p < 0.05) and frontal plane (15.8° to 12.3°, p < 0.01). Although total lower limb joint moments remained unchanged, the relative contribution of frontal‐plane ankle moments significantly decreased (15.6% 12.6%, p < 0.05). Conclusion Trunk muscle fatigue reduces trunk stability and ankle mobility during golf swings. Increased lower limb stiffness may act as a compensatory strategy to maintain swing mechanics under fatigued conditions.
Hakukawa et al. (Thu,) studied this question.