UC San Diego

Background: This dissertation aimed to add to the limited body of research on the subjects of PA maintenance, lapses in PA, and relapse into inactivity among Latina participants in PA interventions.

Methods: Study 1 used survival analysis methods to determine the probability of lapses in PA and to identify predictors of time until lapse, among Latina participants in two PA interventions. Study 2 used qualitative methods (i.e., semi-structured individual interviews with 21 Latina women) to (1) identify facilitators and barriers to PA maintenance; (2) examine similarities and differences between those who maintained PA and those who did not; and (3) create a conceptual model to understand determinants of PA maintenance. Study 3 was a pilot randomized controlled trial (N=27) that used a nested analysis of quantitative and qualitative data to (1) assess maintenance of PA among Latina women who completed a PA intervention; (2) understand whether participants were satisfied or dissatisfied with their maintenance; (3) evaluate the feasibility and preliminary efficacy of smartphone apps for PA maintenance; and (4), explore the role that smartphone apps played in PA maintenance (if any).

Results: Study 1 revealed predictors of earlier lapse, including 2-month scores of Self-Efficacy and various Processes of Change. With one exception, environmental and individual factors were not predictive of earlier lapse. Study 2 identified potential facilitators of PA maintenance: habit, ability to overcome obstacles, specific sources of motivation, having knowledge and skills to maintain PA, and a supportive social and built environment. In study 3, mean minutes/week of self-reported moderate to vigorous PA (MVPA) was 16.85 (SD=24.73) before the intervention, 230.50 (SD=199.29) immediately after the intervention, and 163.10 (SD=125.49) after the maintenance period. There were significant effects of time, but not of group assignment, on self-reported PA. Nine (64%) enhanced maintenance participants reported using apps for PA maintenance. Reasons for not using apps included not finding them appealing or necessary.

Conclusions: Lapse and relapse into inactivity were not pre-determined by individual or environmental factors; skills needed to prevent such events and achieve long-term maintenance of PA outcomes may be taught and need to be incorporated into future PA interventions.