Motivational processes involved in long-term exercise engagement: A multiple case study testing Self-Determination Theory in a sample of older adults with mild cognitive impairment and early dementia

Exercise and physical activity are thought to confer widespread health benefits such as, slowing cognitive and physical decline and reducing falls in people with mild cognitive impairment (MCI) and early dementia. However, long-term exercise and physical activity engagement in this population is poor. This study aimed to explore the motivational processes involved in long-term engagement to a home-based exercise and activity intervention among people with MCI and early dementia and to test the validity of Self-determination Theory (SDT) propositions. Multiple case studies spanning 24 months were undertaken with a sample of 12 participants and their carers. Qualitative data (face-to-face interviews and telephone calls) and quantitative data (exercise diaries) were collected. Qualitative interviews were transcribed and analysed using thematic analysis. Descriptive statistics were calculated for quantitative data and used to enhance interpretation of case studies. Data analysis was performed using pattern matching logic in which the findings of each case study were compared with the theoretical propositions of SDT. Cross-case synthesis identified four profiles of participants: Long-term engagement - continuation of exercises and physical activities for 24 months; long-term partial engagement - stopped the exercises after 12 months, but continued the physical activities for 24 months; short-term engagement - stopped the exercises and physical activities after 12 months; lack of engagement - exercises and physical activities discontinued by 6 months. SDT could be used to understand the motivational processes involved in long-term engagement. Aligned with SDT, the provision of basic needs support over time and intrinsic motivation were crucial for long-term exercise and physical activity engagement. Implications for researchers, practitioners and policy makers supporting older adults with MCI or dementia to engage in physical activity and/or exercise long-term are discussed.