Associations between behavioral regulations and sedentary behavior among older adults

Levels of sedentary behavior increase across the lifespan, making older adults the most sedentary segment of the population. Sedentary behavior is associated with many chronic health conditions including diabetes, cardiovascular disease, and all-cause mortality. Though attempts have been made to reduce or limit sedentary behavior through intervention, little is known about the motivational processes that may be contributing to sedentary time in older adults. It is important to recognize that although physical activity motivation has been extensively researched, physical activity and sedentary behavior are considered independent health behaviors and the same motivational processes that contribute to the upregulation of physical activity may not adequately explain the downregulation (i.e., limiting or reducing) of sedentary behavior. Therefore, the purpose of this thesis is to capture behavioral regulations (specified within Self-Determination Theory) to engage in physical activity and limiting sedentary behavior and examine associations between these behavioral regulations and average daily sedentary time in older adults. Older adults, age 60+ years, completed a baseline questionnaire indicating their behavioral regulations to limit sedentary behavior and to engage in physical activity, then wore an activity monitor for the following two weeks to collect their average daily sedentary time. Results regarding behavioral regulations to limit sedentary behavior indicated that only integrated (ß = -.203, p = .006) and intrinsic regulations (ß = -.185, p = .012) significantly and negatively predicted average daily sedentary time. When all behavioral regulations to limit sedentary behavior were included in the same model, no behavioral regulation significantly predicted average daily sedentary time. Results regarding behavioral regulations to engage in physical activity revealed that only integrated regulation significantly and negatively predicted average daily sedentary time (ß = -.205, p = .007). This negative association remained significant when all behavioral regulations to engage in physical activity were included in the same model (ß = .240, p = .032). This is one of the first studies to assess associations between behavioral regulations to limit sedentary behavior and to engage in physical activity and test their associations with average daily sedentary time among older adults. Results indicate distinct differences between behavioral regulations for limiting sedentary behavior and engaging in physical activity in predicting subsequent average daily sedentary time. Though across both sets of behavioral regulations more autonomous, self-determined behavioral regulations appeared to be associated with average daily behavior compared to more controlling behavioral regulations. Ultimately, this study fills an important knowledge gap by exploring associations between behavioral regulations to limit sedentary behavior and engage in physical activity and subsequent average daily device-based sedentary time. This work is an essential first step in developing effective interventions designed to limit or reduce sedentary behavior among older adults