Supervised Exercise in Women With Breast Cancer

Breast cancer survivors frequently experience chronic physical, physiological, and psychological sequelae that affect quality of life, and few meet physical activity recommendations during adjuvant treatment due to fatigue, pain, lack of time, and low motivation. Most prior research on exercise and motivation in this population has drawn on the theory of planned behaviour or social cognitive theory, with fewer studies grounded in Self-Determination Theory (SDT). According to SDT, motivation for physical activity depends on the satisfaction of three basic psychological needs (autonomy, competence, and relatedness), whose fulfilment is associated with more self-determined motivation, greater adherence, and psychological well-being. This single-arm pilot intervention study analysed changes in psychological and motivational variables (exercise behavioural regulation, basic psychological needs, self-esteem), as well as changes in quality of life, well-being, physical abilities, body composition, and physical exercise frequency, in women who had recently undergone breast cancer surgery and were undergoing adjuvant treatment. The 14-week programme consisted of two supervised 1-hour sessions per week plus one additional hour of independent physical activity, addressing joint mobility, flexibility, aerobic exercise, strength, relaxation techniques, and breathing/posture education, while supporting autonomy (choice of exercises), competence (instruction on the purpose/benefits of each activity), and relatedness (group walks and a WhatsApp support group). Assessments were taken before and after the intervention using validated questionnaires and physical/anthropometric tests.