A biomechanical approach to understanding deficits in jump performance with aging

Research Objectives: To investigate the effect of aging on jump performance, joint-specific extensor moments and their relationships during counter-movement jump (CMJ).

Design: Cross-sectional study.

Setting: University laboratory.

Participants: Young adults; n = 13. Older adults; n = 10.

Interventions: Not applicable.

Main Outcome Measures: Jump height (JHt) difference between older vs young adults was examined. Lower extremity joint-specific extensor moments during concentric phase and peak JHt of CMJ were calculated and compared between young and older adults. Within and between 2x3 (group x joints) repeated measures ANOVA were used for all the comparative analysis. Group wise (young vs older) relationships between joint-specific extensor moments and JHt were examined. All moments used in the analysis were normalized for body weight.

Results: JHt was lower in older adults versus young adults (p < 0.001). In young adults, the ankle and knee extensor moments were lower than that of the hip (p < 0.001 for both). In older adults, the knee extensor moment was lower than the ankle and hip (p < 0.01 for both). The knee and hip extensor moments were lower in older versus young adults (knee: p = 0.003; hip: p < 0.001), with the hip moment reduced by ~50%. JHt showed positive relationship with the ankle and hip extensor moments in young (p = 0.01 - 0.013) and older adults (p = 0.001 - 0.002).

Conclusions: JHt and extensor moments of the knee and hip lower with aging. Irrespective of age, JHt is influenced by ankle and hip extensor moments. Specifically, critical deficit of the hip extensor moment occurs with aging. It is unclear if the aging-associated deficit in the knee extensor moment affects stabilization or acts a synergist to the hip and ankle extensor moment during CMJ.

Author(s) Disclosures: Not applicable.