"Finding my own motivation" - A Mixed Methods Study of Exercise and Behaviour Change Support During Oncological Treatment.

Background: Exercising during oncological treatment is beneficial but challenging for persons with cancer and may require strategies to increase motivation. Behaviour change support, including specific behaviour change techniques (BCTs), have been used to facilitate exercise in persons undergoing oncological treatment, but more detailed knowledge from an individual perspective is needed to inform clinical practice. The aims were to explore the motivational experiences of exercise combined with behaviour change support, and to describe how specific BCTs were valued among persons exercising during oncological treatment.

Methods: A mixed-methods study was conducted using semi-structured interviews (n = 18) and a questionnaire (n = 229). Participants with breast, colorectal or prostate cancer who completed or dropped out of a six-month exercise programme during oncological treatment were included. The interviews were analysed with thematic analysis and the questionnaire with descriptive statistics (median and interquartile range).

Results: The participants underwent a motivational process through the exercise programme. By experiencing 'Health gains and mastery', 'Learning', 'Affinity', 'Commitment', and 'Managing challenges', they found incentives that fostered feelings of autonomy, competence and relatedness, leading to an increased motivation to exercise. Social support from coaches, structuring the physical environment with scheduled sessions, self-monitoring with resistance training log, and feedback based on heart rate monitor and fitness tests were the most valued BCTs.

Conclusions: The results indicate the importance of finding incentives and creating an environment that fosters autonomy, competence and relatedness to motivate persons to exercise during oncological treatment. Some BCTs appear particularly useful and may be used by health professionals to increase patients' motivation to exercise.