The development, delivery and evaluation of a physical activity maintenance intervention.

The number of adults living with chronic health conditions and co-morbidities (e.g., diabetes and depression) is expected to rise by 2035 resulting in significant health and social care challenges (Department of Health, 2012). Supporting people with long-term conditions into better physical and mental health is a public health priority (NICE, 2009). One common approach used to manage or prevent a range of chronic health conditions is physical activity (PA). Evidence supports the short-term effects of PA interventions but a decline in PA levels occurs after an intervention ends (Foster, et al., 2012). Considering the lack of long-term effectiveness of interventions, this thesis explored the active ingredients of PA maintenance (e.g., determinants and behaviour change techniques [BCTs]) through the development, delivery and evaluation of a theory-based PA maintenance intervention. The intervention was developed using intervention mapping principles (Bartholomew, Parcel, Kok, & Gottlieb, 2006). A scoping review explored the intervention components, theories, determinants and BCTs for PA maintenance across at least six months in clinical populations. Multiple theories, determinants and BCTs were found meaning the important components for intervention development were inconclusive. Research gaps were identified, which was addressed through a qualitative study (Study 1). Study 1 investigated the determinants and strategies for successful and unsuccessful maintenance in completers of physical activity referral schemes (PARS). Determinants included: congruence between outcome expectations, experiences and values; social support; and, overcoming barriers. Multiple cognitive-behavioural strategies for PA, condition management and coping were identified, including self-monitoring and pacing. Recommendations included interventions to adopt a person-centred integrative approach, such as motivational interviewing (Miller & Rollnick, 2013) and cognitive-behavioural techniques (MI-CB; Naar-King et al., 2013; Hogden et al., 2012).A RCT pilot study was conducted (Study 2a) to test the efficacy and feasibility of the MI-CB intervention within a PARS setting. The MI-CB group maintained PA at six months post-PARS and enhanced barrier self-efficacy and physical outcome experiences but not social support, coping strategies or BMI compared to usual care. The intervention was largely feasible and generated excellent adherence rates (95%). A treatment fidelity (TF) framework was adopted (Study 2b) assessing fidelity of design, training, delivery, receipt and enactment (Bellg et al., 2004). Results indicated that the intervention provider was not proficient in delivering all MI-CB components (e.g., complex reflections). The findings suggested that on-going supervision was needed to ensure practitioner competence. The contrast between low fidelity to MI-CB delivery and intervention efficacy suggested other variables influenced intervention effectiveness, such as therapeutic alliance, intervention receipt and enactment. Outcomes from this thesis confirm that PA maintenance is a complex process in adults with chronic health conditions, involving multiple theoretical determinants and strategies. A large scale trial is warranted to compare the efficacy of MI-CB to single approaches, such as MI and CBT.