title: Objective light-intensity physical activity associations with rated health in older adults.
abstract: The extent to which light-intensity physical activity contributes to health in older adults is not well known. The authors examined associations between physical activity across the intensity spectrum (sedentary to vigorous) and health and well-being variables in older adults. Two 7-day assessments of accelerometry from 2005 to 2007 were collected 6 months apart in the observational Senior Neighborhood Quality of Life Study of adults aged >65 years in Baltimore, Maryland, and Seattle, Washington. Self-reported health and psychosocial variables (e.g., lower-extremity function, body weight, rated stress) were also collected. Physical activity based on existing accelerometer thresholds for moderate/vigorous, high-light, low-light, and sedentary categories were examined as correlates of physical health and psychosocial well-being in mixed-effects regression models. Participants (N = 862) were 75.4 (standard deviation, 6.8) years of age, 56% female, 71% white, and 58% overweight/obese. After adjustment for study covariates and time spent in moderate/vigorous physical activity and sedentary behavior, low-light and high-light physical activity were positively related to physical health (all P < 0.0001) and well-being (all P < 0.001). Additionally, replacing 30 minutes/day of sedentary time with equal amounts of low-light or high-light physical activity was associated with better physical health (all P < 0.0001). Objectively measured light-intensity physical activity is associated with physical health and well-being variables in older adults.
authors.affiliation: Stanford Prevention Research Center, Department of Medicine, Stanford University School of Medicine, California 94305-5411, USA. mbuman@stanford.edu
authors.forename: Matthew P
authors.initials: MP
authors.lastname: Buman
authors.forename: Eric B
authors.initials: EB
authors.lastname: Hekler
authors.forename: William L
authors.initials: WL
authors.lastname: Haskell
authors.forename: Leslie
authors.initials: L
authors.lastname: Pruitt
authors.forename: Terry L
authors.initials: TL
authors.lastname: Conway
authors.forename: Kelli L
authors.initials: KL
authors.lastname: Cain
authors.forename: James F
authors.initials: JF
authors.lastname: Sallis
authors.forename: Brian E
authors.initials: BE
authors.lastname: Saelens
authors.forename: Lawrence D
authors.initials: LD
authors.lastname: Frank
authors.forename: Abby C
authors.initials: AC
authors.lastname: King
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006304:Health Status; D006305:Health Status Indicators; D006306:Health Surveys; D006801:Humans; D008297:Male; D008991:Monitoring, Physiologic / Q000295:instrumentation / Q000379:methods; D009043:Motor Activity / Q000502:physiology*; D011788:Quality of Life; D012111:Residence Characteristics; D057185:Sedentary Behavior; D013315:Stress, Psychological; D014504:Urban Health