Age-related changes in maximal hip strength and movement speed.

BACKGROUND We quantified age-related decreases in the ability of female participants to generate whole leg movements about the hip. METHODS We measured maximum hip strength and hip velocity in 12 young and 12 older healthy women. Both capabilities could help fall prevention by contributing to fast leg movements. We also measured maximum velocities as a function of isotonic load. RESULTS Young participants produced 107.6 +/- 25.4 N-m (mean +/- SD) isometric torque in flexion and 109.3 +/- 22.3 N-m in extension. Older participants produced 22% and 31% lower torques, respectively (p<.001). Young participants generated maximum velocities of 362.8 +/- 51.5 degrees/s in flexion and 371.5 +/- 54.2 degrees/s in extension. Older participants produced 16% lower velocities in both directions (p<.001). Older participants also produced lower velocities as a function of load (p<.001), and lower maximum power (p<.001). CONCLUSION Both maximum strength and velocity contribute to reduced ability to move the leg quickly with age.