0 avis
Exploring boundary conditions of sustained physical activity: implications for theory and practice.
Archive ouverte
Edité par CCSD -
Objective: Sustained physical activity is crucial for health and is often referred to as 'physical activity maintenance.' However, this concept lacks consensus, possibly due limited study of the 'boundary conditions' under which this phenomenon occurs. This gap limits both theoretical development and interventional applications. This study examined the boundary conditions of two operational definitions of physical activity maintenance (activity threshold and timescale) and how their formulation impacts the detection of sustained physical activity phenomena. Methods: We analyzed 352 time series (length=182 days) of moderate-to-vigorous physical activity (MVPA) collected daily with Fitbit from participants in a weight loss intervention. Two activity thresholds were defined based on participants’ baseline intentions and physical activity levels: a) 150 minutes of MVPA/week for participants below this threshold at baseline (subsample BL-Inactive; n=101), and b) current level of MVPA/week for those exceeding 150 minutes of MVPA/week at baseline (subsample BL-Active; n=251). Regression trees were used to examine changes in physical activity trajectories using different boundary definitions of timescales (7, 14, 28, and 56 days). Results: At finer-grained timescales (7 days), physical activity exhibited repeated fluctuations, with sustained activity patterns in 27% of BL-Inactive and 5% of BL-Active participants. At coarser-grained timescales (56 days), activity trajectories were more stable, with sustained activity percentages increasing to 71% and 26%. Conclusions: Varying boundary conditions reveal different ways of conceptualizing sustained physical activity phenomena, leading to plausibly distinct conclusions about behavioral maintenance. These results highlight the importance of carefully studying boundary conditions as critical for robust theory and practice development.
Consulter en ligne
Suggestions
Du même auteur
