Testing motivational and self-regulatory mechanisms of action on device-measured physical activity in the context of a weight loss maintenance digital intervention ; A secondary analysis of the NoHoW trial

Funding Information: This project has received funding from the European Union's Horizon 2020 research and innovation program under grant agreement No 643309. The material presented and views expressed here are the responsibility of the author(s) only. The EU Commission takes no responsibility for any use made of the information set out. Funding Information: The NoHoW Trial was funded by the European Union’s Horizon 2020 Research and Innovation Programme (grant agreement number 643309). A detailed description of the NoHoW trial procedures can be found elsewhere ( Marques et al., 2021 ; Scott et al., 2019 ). The trial was registered with the ISRCTN registry (ISRCTN88405328). Ethical approval was granted by all local institutional ethics committees at the Universities of Lisbon (17/2016; 20-Feb-2017), Leeds (17–0082; 27-Feb-2017), and the Capital Region of Denmark (H-16030495; 8-Mar-2017). Participants were assigned to one of four intervention conditions that have access to different theory-based digitally delivered content: Publisher Copyright: © 2022 The Authors ; Background: To date, few digital behavior change interventions for weight loss maintenance focusing on long-term physical activity promotion have used a sound intervention design grounded on a logic model underpinned by behavior change theories. The current study is a secondary analysis of the weight loss maintenance NoHoW trial and investigated putative mediators of device-measured long-term physical activity levels (six to 12 months) in the context of a digital intervention. Methods: A subsample of 766 participants (Age = 46.2 ± 11.4 years; 69.1% female; original NoHoW sample: 1627 participants) completed all questionnaires on motivational and self-regulatory variables and had all device-measured physical activity data available for zero, six and 12 months. We examined the direct and indirect effects of Virtual Care Climate on post intervention changes in moderate-to-vigorous physical activity and number of steps (six to 12 months) through changes in ...