Background: Short-term prospective studies have shown physical activity to be related to functional status. To our knowledge, the association between physical activity levels and functional status over a longer period has not been established.
Methods: Two hundred twenty-nine older women (mean age, 74.2 years) who were involved in a randomized controlled walking intervention from 1982 to 1985 were subsequently followed up until December 1999. Physical activity was assessed in 1985, 1995, and 1999 using a physical activity questionnaire and a physical activity monitor. In 1999, functional status was assessed by self-report and performance-based measures.
Results: Subjective and objective measures of physical activity in 1985 independently predicted gait speed in 1999 after controlling for age, chronic conditions, and activity limitation (subjective model-adjusted R2 = 0.09 [P=.03]; and objective model-adjusted R2 = 0.13 [P=.008]). The consistency of physical activity participation from 1985 to 1995 was also related to functional status in 1999. Women who were always active had the best functional status and women who were always inactive had the worst functional status. For difficulty with activities of daily living: those always active, 17 (37.8%) of 45 women; those inconsistently active, 24 (40.0%) of 60 women; and those always inactive, 39 (59.1%) of 66 women (chi2 for trend P=.02). For score on the Physical Performance Test: those always active, 24.9; those inconsistently active, 24.5; and those always inactive, 23.8 (analysis of variance with linear contrasts P=.04). For gait speed: those always active, 1.17 m/s; those inconsistently active, 1.15 m/s; and those always inactive, 1.03 m/s (analysis of variance with linear contrasts P=.002).
Conclusion: We demonstrated a significant relation between physical activity during a 14-year period and current functional status in older women, thus suggesting that physical activity plays a role in maintaining functional ability later in life.