title: Intensity of physical activity in the energy expenditure of older adults.
abstract: This study examined the intensity of activity contributing to physical activity energy expenditure in older adults. In 57 men and women aged ≥ 65, total energy expenditure (TEE) was measured using doubly labeled water and resting metabolic rate was measured using indirect calorimetry to calculate a physical activity index (PAI). Sedentary time and physical activity of light and moderate to vigorous (mod/vig) intensity was measured using an accelerometer. The subjects were 75 ± 7 yrs (mean ± SD) of age and 79% female. Subjects spent 66 ± 8, 25 ± 5, and 9 ± 4% of monitor wear time in sedentary, light, and mod/vig activity per day, respectively. In a mixture regression model, both light (β = 29.6 [15.6-43.6, 95% CI]), p < .001) and mod/vig intensity activity (β = 28.7 [7.4-50.0, 95% CI]), p = .01) were strongly associated with PAI, suggesting that both light and mod/vig intensity activities are major determinants of their physical activity energy expenditure.
authors.affiliation: Department of Kinesiology, University of Wisconsin, Madison, WI.
authors.forename: Lisa H
authors.initials: LH
authors.lastname: Colbert
authors.forename: Charles E
authors.initials: CE
authors.lastname: Matthews
authors.forename: Dale A
authors.initials: DA
authors.lastname: Schoeller
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Havighurst
authors.forename: KyungMann
authors.initials: K
authors.lastname: Kim
mesh_terms: D061725:Accelerometry / Q000379:methods; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000502:physiology / Q000523:psychology; D002153:Calorimetry, Indirect / Q000379:methods; D004734:Energy Metabolism / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D009043:Motor Activity / Q000502:physiology*; D057185:Sedentary Behavior