Development of a training-oriented wearable knee joint exoskeleton for forming a scientific force application pattern in squat tasks

Background Squat training enhances athletic performance but poses knee injury risks when the technique is poor. Objective Develop a resistance-type wearable knee exoskeleton to cultivate a hip-dominant, knee-safe squat pattern. Methods Fifteen healthy men performed squats with either the exoskeleton or with barbells at three matched loads. Three-dimensional motion, ground-reaction force, and electromyography data were processed in OpenSim and MATLAB to quantify joint kinematics, power share, and muscle contribution. Results The exoskeleton significantly reduced average angular velocity at the hip, knee, and ankle (p < 0.05), increasing hip power contribution by 20%–40% while decreasing knee contribution by 20%–30%, confirming a hip-driven pattern. However, knee and ankle ranges of motion decreased by 7°–9°, and vastus medialis activation dropped by ∼50% (p < 0.05). Conclusion The device effectively standardizes squat mechanics and off-loads the knee, yet individualized tuning and auxiliary mobility work are recommended to optimize training transfer and preserve functional range of motion.