THE EFFECT OF HIP AND ANKLE FLEXIBILITY TRAINING ON OLDER ADULT GAIT.

Abstract

Purpose/Hypothesis: The purpose of this study was to examine effects of a hip and ankle stretching intervention on flexibility and gait biomechanics of older adults not previously active in exercise participation. It was hypothesized that increases in hip extension and ankle plantar flexion range of motion (ROM) would occur from the intervention. Accompanying the flexibility increases were expected increases in freely chosen gait speed (FCGS), stride length (SL), and joint angular displacement. Subjects: 37. Materials/Methods: Healthy older adults 62 to 82 years of age participated. Assessment of each participant was made before and after an 8 week period. The experimental (EXP) group participated in home flexibility training for the 8 weeks while the control (CON) group made no changes to their physical activity routine. Both groups had weekly visits with the primary investigator to encourage compliance and receive exercise training as needed. Hip extensor flexibility was measured with participants in the Thomas Test position and ankle plantar flexor flexibility was measured as dorsiflexion ROM with the knee extended. Gait variables were measured during both FCGS and set gait speed (SGS) (1.5 m/s) trials. Data were captured for gait variables using a video motion analysis system. Results: Hip extensor flexibility increased as measured by combined passive ROM of hip extension and knee flexion in the Thomas Test position from 59.7 deg pre- to 66.5 deg post-assessment in the EXP group (p = 0.002). Ankle plantar flexor flexibility increased from 7.8 deg pre- to 11.3 deg post-assessment in the EXP group (p = 0.001). Freely chosen walking speed increased from 1.23 m/s pre- to 1.30 m/s post-assessment in the EXP group (p < 0.001). During gait, increasing trends were noted in hip angular displacement and SL from pre- to post-assessment in the EXP group at both FCGS and SGS, but increases were not statistically significant compared to the CON group. No trends of change were noted in ankle angular displacement at either gait speed. Conclusions: Healthy, previously non-exercising older adults demonstrate functional benefit from 8 weeks of flexibility training. The implication is that joint ROM is a specific age-associated impairment that can be modified to enhance older adult gait function. The promotion of routine stretching exercise for healthy individuals has been criticized due to insufficient evidence of benefit. Based on results of this study, recommendations for routine hip extensor and ankle plantar flexor stretching appear reasonable for healthy older adults. Clinical Relevance: The findings of this study are clinically significant. For a person to functionally ambulate in the community, a minimum level of gait speed is required. Decline in gait speed is directly related to age-associated disability. This study supports previous suggestions that joint ROM may be a key impairment dictating gait change in older adults. Application of such a flexibility program for older adults with conditions that exacerbate ROM impairment may result in even greater improvements.