Background Squatting is essential for daily activities but may risk knee injury due to excessive loads. Tai Chi squatting (TCS), characterized by slow, controlled movements, is hypothesized to reduce joint load compared to standard squatting (SS), though biomechanical comparisons remain scarce. This study aimed to biomechanically compare TCS and SS, with a focus on knee joint kinematics, kinetics, muscle activation, and internal stress distribution. Methods Twelve experienced Tai Chi practitione