From adoption to adherence: the processes impacting physical activity engagement

Objective: Adherence to physical activity interventions is poorly understood. Using Self-Determination Theory as an organising framework, this study explored the processes of physical activity adoption through to adherence of sedentary University employees participating in a 16-week lunchtime walking programme (‘Step by Step’). Design: An interpretative phenomenological approach was used to answer three inter-related questions: How do sedentary adults experience the transition from a sedentary to the commencement of a physically active lifestyle? How do adults cope with temptations of returning to a sedentary lifestyle? What are the main factors affecting relapse and drop-out from a physical activity programme? Method: 17 participants were interviewed one-to-one on three separate occasions (prior, at mid-term and immediately post) during the 16-week intervention (10-week group led followed by six-week independent phase). Interviews explored motivations for engagement and adherence to the walking programme, satisfaction of the three basic psychological needs within the activity, challenges regarding handling barriers, and perceived social/autonomy support throughout the programme. Results: Introjected reasons (guilt) for engagement was a prominent theme during the adoption stage of the intervention. As the programme continued, temptations of returning to a sedentary lifestyle were reduced in individuals who demonstrated more internalised and integrated motivations for engagement (enjoyment of the activity). Adhering individuals experienced increases in competence, relatedness and to some extent autonomy. Conclusions: Findings support the hypothesised inter-relationships between need satisfaction, self-regulation and positive behavioural aspects towards physical activity and offers additional in-depth and longitudinal detail to complement existing cross-sectional and qualitative research.