Greater physical activity of an aerobic nature ( categorized by a variety of methods ) was associated with higher functional status ( expressed by a host of outcome measures ) in older age .
For functional independence , moderate ( and high ) levels of physical activity appeared effective in conferring a reduced risk ( odds ratio ~0.5 ) of functional limitations or disability .
Limitation in higher level performance outcomes was reduced ( odds ratio ~0.5 ) with vigorous ( or high ) activity with an apparent dose-response of moderate through to high activity .
Exercise training interventions ( including aerobic and resistance ) of older adults showed improvement in physiological and functional measures , and suggestion of longer-term reduction in incidence of mobility disability .
A relatively high level of physical activity was related to better cognitive function and reduced risk of developing dementia ; however , there were mixed results of the effects of exercise interventions on cognitive function indices .
Conclusions There is a consistency of findings across studies and a range of outcome measures related to functional independence ; regular aerobic activity and short-term exercise programmes confer a reduced risk of functional limitations and disability in older age .
Although a precise characterization of a minimal or effective physical activity dose to maintain functional independence is difficult , it appears moderate to higher levels of activity are effective and there may be a threshold of at least moderate activity for significant outcomes
Background The purpose was to conduct systematic review s of the relationship between physical activity of healthy community-dwelling older ( > 65 years ) adults and outcomes of  functional limitations , disability , or loss of independence .
Type and intensity of activity and risk of mobility limitation: the mediating role of muscle parameters.
OBJECTIVES To investigate the association between different types of physical activity behavior and  incident mobility limitation in older men and women and to examine whether muscle parameters mediate these associations . DESIGN Cohort study with 4.5-year follow-up . SETTING Metropolitan areas surrounding Pittsburgh , Pennsylvania , and Memphis , Tennessee . A r and om sample of white Medicare beneficiaries and all age-eligible blacks . PARTICIPANTS Three thous and seventy-five black and white men and women aged 70 to 79 with no self-reported difficulty walking one-quarter of a mile or climbing 10 steps , enrolled in the Health , Aging and Body Composition ( Health ABC ) Study . MEASUREMENTS Participants were classified as exercisers ( reporting > or = 1,000 kcal/wk of exercise activity ) , lifestyle active ( reporting < 1,000 kcal/wk of exercise activity and > or = 2,719 kcal/wk of total physical activity ) , or inactive ( reporting < 1,000 kcal/wk of exercise activity and < 2,719 kcal/wk of total physical activity ) . The study outcome , incident mobility limitation , was defined as two consecutive , semiannual self-reports of any difficulty walking one quarter of a mile or climbing 10 steps . Thigh muscle area , thigh muscle attenuation ( a marker of fat infiltration in muscle ) , appendicular lean soft tissue mass , and isokinetic knee extensor strength were examined as potential mediators . RESULTS Over 4.5 years , 34.3 % of men and 47.4 % of women developed mobility limitation . Inactive persons had twice the risk of incident mobility limitation as exercisers ( hazard ratio (HR)=2.08 , 95 % confidence interval (CI)=1.60 - 2.70 , for men , HR=1.98 , 95 % CI=1.51 - 2.60 , for women ) . Lifestyle-active men and women had an intermediate risk ( HR=1.47 and 1.44 , respectively ) . For the lifestyle active and inactive , absence of walking activity conferred an additional risk of mobility limitation . Muscle parameters did not mediate the relationship between physical activity and mobility limitation , except for knee extensor strength in men . CONCLUSION Exercise and an active lifestyle that includes walking protect against mobility loss in older men and women . Activity effects on muscle parameters do not explain this association
Greater physical activity of an aerobic nature ( categorized by a variety of methods ) was associated with higher functional status ( expressed by a host of outcome measures ) in older age .
For functional independence , moderate ( and high ) levels of physical activity appeared effective in conferring a reduced risk ( odds ratio ~0.5 ) of functional limitations or disability .
Limitation in higher level performance outcomes was reduced ( odds ratio ~0.5 ) with vigorous ( or high ) activity with an apparent dose-response of moderate through to high activity .
Exercise training interventions ( including aerobic and resistance ) of older adults showed improvement in physiological and functional measures , and suggestion of longer-term reduction in incidence of mobility disability .
A relatively high level of physical activity was related to better cognitive function and reduced risk of developing dementia ; however , there were mixed results of the effects of exercise interventions on cognitive function indices .
Conclusions There is a consistency of findings across studies and a range of outcome measures related to functional independence ; regular aerobic activity and short-term exercise programmes confer a reduced risk of functional limitations and disability in older age .
Although a precise characterization of a minimal or effective physical activity dose to maintain functional independence is difficult , it appears moderate to higher levels of activity are effective and there may be a threshold of at least moderate activity for significant outcomes
Background The purpose was to conduct systematic review s of the relationship between physical activity of healthy community-dwelling older ( > 65 years ) adults and outcomes of  functional limitations , disability , or loss of independence .