E-25 Free Communication/Poster - Correlates and Behavioral Aspects of Physical Activity Friday, June 3, 2016, 7: 30 AM - 12: 30 PM Room: Exhibit Hall A/B
PURPOSE: This 14-day daily diary study tested a dual-process model of motivation to determine the between-person (time-invariant) and within-person (time-varying) processes associated with older adults’ daily sedentary behavior.
METHODS: Older adults (n=100) used tablet computers to rate their motivation and sedentary behavior at the beginning and end of each day, respectively. Participants also wore ActivPAL3 activity monitors throughout the study to objectively-measure sedentary behavior. A series of multilevel models were estimated to predict daily sedentary behavior, action planning, and intention formation.
RESULTS: Both self-reported and objectively-measured sedentary behavior were (1) negatively associated with planning at the within-person level (self-reported behavior: γ10 = -0.79, p < .05; monitored behavior: γ10 = -0.51, p < .05), but not the between-person level, and (2) positively associated with habit strength for sedentary behavior (self-reported behavior: γ02 = 36.32, p < .05; monitored behavior: γ02 = 19.97, p < .05). Daily action plans to limit sedentary behavior were (1) positively associated with task self-efficacy at the within-person level, but negatively associated at the between-person level (γ10 = 0.14, p < .05, γ01 = -0.59, p < .05, respectively), and (2) positively associated with intentions at the between- and within-person level (γ02 = 1.17, p < .05, γ20 = 0.20, p < .05, respectively). Intentions to limit sedentary behavior were (1) positively associated with task self-efficacy at the between and within-person level (γ01 = 0.96, p < .05, γ10 = 0.61, p < .05, respectively), but (2) not associated with light-intensity physical activity outcome expectations, sedentary behavior risk perceptions, or sedentary behavior habit strength.
CONCLUSIONS: This study was the first to systematically identify a set of controlled and automatic processes associated with older adults’ daily sedentary behavior. Interventions aiming to reduce sedentary behavior in older adults should interrupt established sedentary habits and promote counterhabitual daily intentions and action plans. This research was supported by the Paffenbarger-Blair Fund for Epidemiological Research on Physical Activity from the American College of Sports Medicine Foundation.