title: Dose-response walking activity and physical function in older adults.
abstract: The aim of this study was to examine the dose-response relationship between walking activity and physical function (PF) in community-dwelling older adults. Physical activity (PA, pedometry) and PF (self-report [SF-36] and 6-minute walk test [6MWT]) were assessed in 836 individuals. Accumulated PA was categorized into four groups (1 = ≤ 2,500; 2 = 2,501-5,000; 3 = 5,001-7,500; and 4 = ≥ 7,501 steps/day). Across individual groups 1-4, SF-36 scores increased from 66.9 ± 25.0% to 73.5 ± 23.2% to 78.8 ± 19.7% to 81.3 ± 20.6%, and 6MWT increased from 941.7 ± 265.4 ft to 1,154.1 ± 248.2 ft to 1,260.1 ± 226.3 ft to 1,294.0 ± 257.9 ft. Both SF-36 and 6MWT scores were statistically different across all groups, apart from groups 3 and 4. PA and ranks of groups were highly significant predictors (p < .0001) for both SF-36 and 6MWT. There was a positive dose-response relationship evident for both SF-36 and 6MWT with increasing levels of PA. Low levels of PA appear to be an important indicator of poor functionality in older adults.
authors.affiliation: Department of Health, Exercise, and Sport Science, The Citadel, Charleston, SC.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Dondzila
authors.forename: Keith P
authors.initials: KP
authors.lastname: Gennuso
authors.forename: Ann M
authors.initials: AM
authors.lastname: Swartz
authors.forename: Sergey
authors.initials: S
authors.lastname: Tarima
authors.forename: Elizabeth K
authors.initials: EK
authors.lastname: Lenz
authors.forename: Stephanie S
authors.initials: SS
authors.lastname: Stein
authors.forename: Randal J
authors.initials: RJ
authors.lastname: Kohl
authors.forename: Scott J
authors.initials: SJ
authors.lastname: Strath
mesh_terms: D000054:Acceleration; D000368:Aged; D000704:Analysis of Variance; D000886:Anthropometry; D003430:Cross-Sectional Studies; D005080:Exercise Test / Q000379:methods*; D017079:Exercise Tolerance / Q000502:physiology*; D005260:Female; D015577:Geriatric Assessment / Q000379:methods; D006801:Humans; D057187:Independent Living; D008297:Male; D008875:Middle Aged; D010809:Physical Fitness / Q000502:physiology*; D013997:Time Factors; D016138:Walking / Q000502:physiology*