A qualitative longitudinal study of motivation in the REtirement in ACTion (REACT) physical activity intervention for older adults with mobility limitations.

BACKGROUND: Physical activity (PA) is beneficial for older adults' health, however they remain the least active age group in the UK. This qualitative longitudinal study aims to understand motivations in older adults receiving the REACT physical activity intervention, through the lens of self-determination theory. METHODS: Participants were older adults randomised to the intervention arm of the Retirement in ACTion (REACT) Study, a group-based physical activity and behaviour maintenance intervention to prevent decline of physical functioning in older adults (≥ 65 years). Stratified purposive sampling by physical functioning (Short Physical Performance Battery scores) and 3-month attendance was employed. Fifty-one semi-structured interviews were conducted at 6, 12 and 24-months with twenty-nine older adults (Mean age (baseline) = 77.9 years, SD 6.86, 69% female) and at 24-months with twelve session leaders and two service managers. Interviews were audio recorded, transcribed verbatim and analysed using Framework Analysis. RESULTS: Perceptions of autonomy, competence and relatedness were associated with adherence to the REACT programme and maintenance of an active lifestyle. Motivational processes and participants' support needs, changed during the 12-month REACT intervention and across the 12-months post-intervention. Group interactions were an important source of motivation during the first six months but increased competence and mobility drove motivation at the later stages (12 months) and post-intervention (24 months). CONCLUSIONS: Motivational support needs vary in different stages of a 12-month group-based programme (adoption and adherence) and post-intervention (long-term maintenance). Strategies to accommodate those needs include, (a) making exercise social and enjoyable, (b) understanding participants' capabilities and tailoring the programme accordingly, (c) capitalising on group support to motivate participants to try other activities and prepare sustainable active living plans. TRIAL REGISTRATION: The REACT study was a pragmatic multi-centre, two-arm, single-blind, parallel-group, RCT (ISRCTN registration number 45627165).