Ecological Momentary Assessment Is a Feasible and Valid Methodological Tool to Measure Older Adults’ Physical Activity and Sedentary Behavior

Ecological momentary assessment (EMA) has the potential to yield new insights into theprediction and modeling of physical activity (PA) and sedentary behavior (SB). The objective ofthis study was to determine the feasibility and validity of an EMA protocol to assess older adults’PA and SB. Feasibility was determined by examining factors associated with EMA surveycompliance and if PA or SB were impacted by EMA survey compliance. Validity wasdetermined by comparing EMA-reported PA and SB to objectively measured PA and SB at theEMA prompt. Over 10 days, older adults (n = 104; Agerange = 60–98 years) received 6 randomlyprompted EMA questionnaires on a smartphone each day and wore an ActivPAL activitymonitor to provide a device-based measure of PA and SB. Participants reported whether theywere currently engaged in PA or SB. Older adults were compliant with the EMA and ActivPALprotocol on 92% of occasions. Differences in EMA compliance differed by weight status.Among overweight and obese older adults EMA compliance differed by sex (OR = 3.15, 95%CI: 1.43, 6.92) and day of week (OR = 1.79, 95% CI: 1.33, 2.41). Among normal weight olderadults, EMA compliance differed by time of day (OR = 1.52, 95% CI: 1.02, 2.30). EMAcompliance did not differ for device-based PA or SB in the 15 min before versus the 15 min afterthe EMA prompt, suggesting that these behaviors did not influence likelihood of responding andresponding did not influence these behaviors (ps > 0.05). When PA was reported through EMA,participants engaged in less device-based PA in the 15 min after compared to the 15 min beforethe EMA prompt (p = 0.01), suggesting possible reactance or a disruption of PA. EMA-reportedPA and SB were positively associated with higher device-based PA and SB in the ±15 min,respectively, supporting criterion validity (ps < 0.05). The assessment of older adults’ PA and SBthrough EMA is feasible and valid, although there may be PA reactance to EMA prompting.Therefore, EMA represents a significant methodological tool that can aid in our understanding ofthe environmental, social, and psychological processes regulating older adults’ PA and SB in thecontext of everyday life