RESUMEN
OBJECTIVES: This study examined whether exercise beliefs and illness perceptions were associated with changes in exercise behaviour following a cancer diagnosis. DESIGN: This study uses a cross-sectional survey of 366 adults with a diagnosis of cancer, who were currently receiving treatment. MAIN OUTCOME MEASURES: The main outcome measures are symptom severity, pre- and post-morbid exercise levels, exercise beliefs, and illness perceptions. RESULTS: The majority of participants decreased their level of exercise after diagnosis (Decreasers; 58.1%). Approximately a third increased participation (Increasers; 30.4%) and a small group maintained (Maintainers; 9.2%) their pre-diagnosis exercise levels. After controlling for symptom severity and time since cancer diagnosis, Decreasers reported lower Self-Efficacy for exercise, higher levels of belief in the Negative Impact on Cancer of exercise, lower levels of Personal Control, and less Emotional Representation of their illness, than Increasers. Decreasers also reported lower levels of Self-Efficacy for exercise than Maintainers. CONCLUSION: The results suggest that identifying unhelpful beliefs about the relationship between exercise and illness during cancer treatment and improving confidence and control of exercise through psycho-educational intervention could be an effective strategy for preventing cancer patients decreasing exercise following their diagnosis.