A randomized trial on the feasibility of high-intensity interval training during chemotherapy in young breast cancer patients.

Chemotherapy used to treat breast cancer (BC) in young women often results in significant side effects, among others myelotoxicity, nausea, neurotoxicity, ataxia, and fatigue. These negative effects can be offset by physical activity employed concurrently with the treatment. One of the training modalities - high-intensity interval training (HIIT) - has been the subject of many studies showing significant health benefits, with the advantage of being time-efficient. The aim of this study was to investigate whether HIIT can be successfully employed for young BC patients undergoing chemotherapy. Forty young (18-40 years old) BC patients scheduled for chemotherapy were randomized to undergo supervised HIIT concurrently with chemotherapy or instructed to perform World Health Organization-recommended volume of daily physical activity (control group). Measurements included retention, adherence to training, and body composition parameters (BMI, muscle mass, fat mass, handgrip strength on affected and unaffected side) measured before and after therapy. HIIT scheduled concurrently with chemotherapy was a feasible approach for young BC patients (retention: 94.74%, adherence: 100%). Employment of HIIT also resulted in higher handgrip strength compared to no supervised training (1.2 kg between-group difference). This study shows that HIIT introduced and conducted along the chemotherapy is feasible for young BC patients. This approach can offset the negative effects of chemotherapy on physical fitness.Trial registrationThe study was registered in the clinicaltrials.gov registry (#NCT06190600) on 05/01/2024, retrospectively registered.