Association between physical function and the load pattern during stepping-up motion in community-dwelling elderly women.

Objective: Stepping-up motion is challenging task for elderly people in daily life. The present study investigated the relationship between the load pattern during stepping-up motion at maximum speed and physical function in elderly women.

Methods: The subjects comprised 109 community-dwelling elderly women (age 72.5±5.3years). The load pattern (maximum load, rate of load production, and stepping-up time) during ascending a 30cm step at maximum speed was measured, using a step up platform that measures the load at the lower and upper level. Physical function, including hip and knee extensor strength and performance on the vertical jump test, one-legged stance test, timed "Up & Go" (TUG) test, and stepping test were measured.

Results: Pearson's correlation analysis showed that stepping-up time was correlated with the maximum load at the lower level (r=-0.51), but not with the maximum load at the upper level. A multiple regression analysis showed that hip extensor strength and performance on the vertical jump, TUG, and stepping tests were significant determinants of the load pattern during stepping-up motion in the elderly women.

Conclusions: Our study revealed that rapid stepping-up ability was more closely related to the maximum load during push-off at the lower level rather than that during weight loading on the upper level, and that the load pattern during stepping-up motion in elderly women was associated with various physical functions such as the hip extensor strength, leg muscle power, dynamic balance function, and agility.