Temporal changes in postural control strategy through single-leg stance practice with active restriction of knee movement.

[Purpose] This study aimed to examine and verify temporal changes in lower limb joint action after 2 weeks of single-leg stance training under active restriction of knee movement. [Participants and Methods] The participants included 28 healthy adult females (mean age, 19.6 ± 1.0 years). A stabile meter was used to measure the center of pressure sway as an index of ankle joint action. In addition, a triaxial accelerometer was used to measure pelvic and knee sways as indices of hip and knee joint actions, respectively. We established two experimental groups: an active-restriction group and an unrestricted group. Measurements of lower limb joint actions were recorded thrice during single-leg stance exercises during the first session of practice, the third session 1 week later, and the sixth session 2 weeks later. [Results] Both groups exhibited shorter total trajectory lengths in sessions three and six than in the first session. The active restriction group showed less knee sway in later sessions, whereas the unrestricted group showed reduced pelvic sway in the third session. [Conclusion] Single-leg stance exercises with active restriction of knee movement may alter the strategy of lower limb joint action.