This study was designed to examine the moderating influence of habit strength on daily action planning effects on physical activity and sedentary behavior. A 2 by 2 design was used with experimental factors corresponding to action planning interventions for (a) engaging in physical activity and (b) limiting or interrupting sedentary behavior. At the end of each day for 1 week, university students (n = 195) completed (a) a questionnaire about their behavior during the day and behavioral intentions for the following day and (b) a planning intervention(s) corresponding to their randomly assigned experimental condition. Action planning increased physical activity in those with weak habits but decreased physical activity in those with strong habits compared with those who did not create action plans. Action planning did not impact sedentary behavior. Action planning was a useful behavior change technique for increasing physical activity in people with weak habits, but may be iatrogenic for those with strong habits.
Jaclyn P. Maher and David E. Conroy
Jaclyn P. Maher and David E. Conroy
This study evaluated how older adults’ daily physical activity covaries with naturally occurring variation in both the duration and patterning of daily sedentary behavior. Older adults (n = 95) wore activPAL3 monitors for 15 consecutive days. Multilevel modeling regressed daily step counts on the frequency of sit-to-stand transitions and the duration of sedentary behavior. At the person-level, older adults who sat less (b = −14.31, p < .001) and stood up more frequently (b = 41.08, p = .01) took more steps on average. At the within-person level, older adults took more steps on days when they sat less than usual (b = −8.29, p < .001) and stood up more frequently than usual (b = 52.75, p < .001). Older adults’ daily physical activity may be influenced by interrupting sedentary behavior more frequently as well as reducing total sedentary behavior. It may be easier to monitor the frequency of discrete behaviors, like standing up, than it is to monitor the duration of continuous behaviors (e.g., walking, sitting).
David E. Conroy, Steriani Elavsky, Shawna E. Doerksen and Jaclyn P. Maher
Social-cognitive theories, such as the theory of planned behavior, posit intentions as proximal influences on physical activity (PA). This paper extends those theories by examining within-person variation in intentions and moderate-to-vigorous physical activity (MVPA) as a function of the unfolding constraints in people’s daily lives (e.g., perceived time availability, fatigue, soreness, weather, overeating). College students (N = 63) completed a 14-day diary study over the Internet that rated daily motivation, contextual constraints, and MVPA. Key findings from multilevel analyses were that (1) between-person differences represented 46% and 33% of the variability in daily MVPA intentions and behavior, respectively; (2) attitudes, injunctive norms, self-efficacy, perceptions of limited time availability, and weekend status predicted daily changes in intention strength; and (3) daily changes in intentions, perceptions of limited time availability, and weekend status predicted day-to-day changes in MVPA. Embedding future motivation and PA research in the context of people’s daily lives will advance understanding of individual PA change processes.
Amanda L. Rebar, Steriani Elavsky, Jaclyn P. Maher, Shawna E. Doerksen and David E. Conroy
Physical activity is regulated by controlled processes, such as intentions, and automatic processes, such as habits. Intentions relate to physical activity more strongly for people with weak habits than for people with strong habits, but people’s intentions vary day by day. Physical activity may be regulated by habits unless daily physical activity intentions are strong. University students (N = 128) self-reported their physical activity habit strength and subsequently self-reported daily physical activity intentions and wore an accelerometer for 14 days. On days when people had intentions that were weaker than typical for them, habit strength was positively related to physical activity, but on days when people had typical or stronger intentions than was typical for them, habit strength was unrelated to daily physical activity. Efforts to promote physical activity may need to account for habits and the dynamics of intentions.
Jaclyn P. Maher, Shawna E. Doerksen, Steriani Elavsky and David E. Conroy
Recent research revealed that on days when college students engage in more physical activity than is typical for them, they also experience greater satisfaction with life (SWL). That work relied on self-reported physical activity and did not differentiate between low levels of physical activity and sedentary behavior. This study was designed to (1) determine if the association between self-reported physical activity and SWL would exist when physical activity was monitored objectively and (2) examine the between- and within-person associations among physical activity, sedentary behavior, and SWL. During a 14-day ecological momentary assessment study, college students (N = 128) wore an accelerometer to objectively measure physical activity and sedentary behavior, and they self-reported their physical activity, sedentary behavior, and SWL at the end of each day. Physical activity and sedentary behavior had additive, within-person associations with SWL across self-reported and objective-measures of behavior. Strategies to promote daily well-being should encourage college students to incorporate greater amounts of physical activity as well as limit their sedentary behavior.
Jaclyn P. Maher, Eldin Dzubur, Jimi Huh, Stephen Intille and Genevieve F. Dunton
This study used time-varying effect modeling to examine time-of-day differences in how behavioral cognitions predict subsequent physical activity (PA). Adults (N = 116) participated in three 4-day “bursts” of ecological momentary assessment (EMA). Participants were prompted with eight EMA questionnaires per day assessing behavioral cognitions (i.e., intentions, self-efficacy, outcome expectations) and wore an accelerometer during waking hours. Subsequent PA was operationalized as accelerometer-derived minutes of moderate- or vigorousintensity PA in the 2 hr following the EMA prompt. On weekdays, intentions positively predicted subsequent PA in the morning (9:25 a.m.–11:45 a.m.) and in the evening (8:15 p.m.–10:00 p.m.). Self-efficacy positively predicted subsequent PA on weekday evenings (7:35 p.m.–10:00 p.m.). Outcome expectations were unrelated to subsequent PA on weekdays. On weekend days, behavior cognitions and subsequent PA were unrelated regardless of time of day. This study identifies windows of opportunity and vulnerability for motivation-based PA interventions aiming to deliver intervention content within the context of adults’ daily lives.