Sex differences in the importance of lower extremity strength and velocity on walking speed.

Research Objectives: To investigate the sex differences in the relative importance of strength and velocity of knee extension and ankle plantar flexion on walking speed in older adults.

Design: This was a cross-sectional observational study.

Setting: Community-based.

Participants: This study included 228 community-dwelling older adults (74.1±5.4 years, 84 males and 144 females).

Interventions: Not applicable.

Main Outcome Measures: Maximum walking speed, muscle strength, and movement velocity were measured in random order on the same day. Knee extension and plantar flexion isometric strength were measured using a handheld dynamometer. Movement velocity was measured using a gyroscope as the maximum angular velocity when the participant performed knee extension and plantar flexion as quickly as possible under a no-load condition.

Results: The mean walking speed was 1.84±0.29 m/s for males and 1.73±0.26 m/s for females. For each sex group, a multiple regression analysis was performed with walking speed as the dependent variable and age, body mass index, strength, and velocity as the independent variables. In males, knee extension velocity (standardized β=0.32, p< 0.01) and plantar flexion velocity (standardized β=0.20, p< 0.05) were identified as significant predictors of walking speed (adjusted R²=0.38, p< 0.01). In females, plantar flexion strength (standardized β=0.21, p< 0.05) and plantar flexion velocity (standardized β = 0.19, p< 0.05) were significant predictors (adjusted R²=0.22, p< 0.01).

Conclusions: The results indicated that the relative importance of knee and ankle muscle strength and movement velocity in determining walking speed varied by sex.

Author(s) Disclosures: The authors have no financial or non-financial conflicts to disclose.