TY  - JOUR
AU  - Maes, Iris
AU  - Mertens, Lieze
AU  - Poppe, Louise
AU  - Vetrovsky, Tomas
AU  - Crombez, Geert
AU  - De Backere, Femke
AU  - Brondeel, Ruben
AU  - Van Dyck, Delfien
PY  - 2023
DA  - 2023/11/23
TI  - Within-Person Associations of Accelerometer-Assessed Physical Activity With Time-Varying Determinants in Older Adults: Time-Based Ecological Momentary Assessment Study
JO  - JMIR Aging
SP  - e44425
VL  - 6
KW  - ecological momentary assessment
KW  - EMA
KW  - associations
KW  - emotions
KW  - physical concerns
KW  - intention
KW  - self-efficacy
KW  - older adult
KW  - mobile phone
AB  - Background: Despite the availability of physical activity (PA) interventions, many older adults are still not active enough. This might be partially explained by the often-limited effects of PA interventions. In general, health behavior change interventions often do not focus on contextual and time-varying determinants, which may limit their effectiveness. However, before the dynamic tailoring of interventions can be developed, one should know which time-dependent determinants are associated with PA and how strong these associations are. Objective: The aim of this study was to examine within-person associations between multiple determinants of the capability, opportunity, motivation, and behavior framework assessed using Ecological Momentary Assessment (EMA) and accelerometer-assessed light PA, moderate to vigorous PA, and total PA performed at 15, 30, 60, and 120 minutes after the EMA trigger. Methods: Observational data were collected from 64 healthy older adults (36/64, 56% men; mean age 72.1, SD 5.6 y). Participants were asked to answer a time-based EMA questionnaire 6 times per day that assessed emotions (ie, relaxation, satisfaction, irritation, and feeling down), the physical complaint fatigue, intention, intention, and self-efficacy. An Axivity AX3 was wrist worn to capture the participants’ PA. Multilevel regression analyses in R were performed to examine these within-person associations. Results: Irritation, feeling down, intention, and self-efficacy were positively associated with subsequent light PA or moderate to vigorous PA at 15, 30, 60, or 120 minutes after the trigger, whereas relaxation, satisfaction, and fatigue were negatively associated. Conclusions: Multiple associations were observed in this study. This knowledge in combination with the time dependency of the determinants is valuable information for future interventions so that suggestions to be active can be provided when the older adult is most receptive. 
SN  - 2561-7605
UR  - https://aging.jmir.org/2023/1/e44425
UR  - https://doi.org/10.2196/44425
UR  - http://www.ncbi.nlm.nih.gov/pubmed/37995131
DO  - 10.2196/44425
ID  - info:doi/10.2196/44425
ER  -