A randomized crossover pilot study conducted by researchers at the University of Sherbrooke and the Research Centre on Aging in Quebec, Canada, investigated whether moderate-to-high-intensity aerobic exercise performed the day before chemotherapy could influence cancer-related fatigue and active versus sedentary behaviors in the days following treatment. The study, published in Translational Exercise Biomedicine (ISSN: 2942-6812), an official partner journal of International Federation of Sports Medicine (FIMS) , provides preliminary evidence that pre-chemotherapy exercise is safe and may offer modest benefits for fatigue management.
In this study, 12 patients aged 45-65 years diagnosed with metastatic breast, colorectal, and prostate cancer undergoing chemotherapy were recruited. Using a crossover design, each participant completed three experimental conditions the day before their chemotherapy session: 1) REST (control condition: 40 minutes seated rest), 2) MOD (moderate continuous aerobic exercise: 30 minutes at 50% of submaximal power), and 3) HIIE (high-intensity interval exercise: ten 1-minute intervals at vigorous intensity with active recovery periods). Both exercise sessions were matched for duration and total mechanical work.
Following each condition, researchers monitored participants for five days post-chemotherapy. Cancer-related fatigue and other symptoms including nausea, pain, mood, sleep quality, muscular soreness were assessed three times daily using visual analog scales following the Ecological Momentary Assessment approach. Sedentary behavior, light physical activity (LPA), and moderate-to-vigorous physical activity (MVPA) were objectively measured using accelerometers.
Cancer-related fatigue fluctuated throughout the day, typically increasing toward evening hours. A significant time effect on cancer-related fatigue was observed on Day 1, Day 3, and Day 4, with a trend on Day 2. Notably, the HIIE condition significantly lessened perceived fatigue on Day 5 post-chemotherapy, suggesting a delayed beneficial effect of high-intensity exercise performed before treatment. However, no significant effects of time, condition, or their interaction were observed on sedentary behaviors, LPA, or MVPA over the five-day follow-up period.
Regarding other treatment-related symptoms, the HIIE condition showed trends toward increased nausea on Day 1 and significant increases on Day 3, while the MOD condition was associated with higher nausea on Day 5. Mood and sleep quality remained relatively stable across conditions.
Prof .Eléonor Riesco, corresponding author of the study and researcher at the University of Sherbrooke and the Research Centre on Aging , highlighted the clinical significance of their findings: " Our study demonstrates that moderate to vigorous aerobic exercise performed the day before chemotherapy is safe and does not exacerbate cancer-related fatigue or other treatment-related symptoms. Importantly, we observed that high-intensity interval exercise may help attenuate fatigue in the days following treatment. These preliminary findings suggest that strategic exercise timing could be a valuable component of supportive cancer care ."
From a clinical translational perspective, this study provides important preliminary evidence that exercise can be safely integrated into pre-treatment routines for patients with advanced cancer. The findings support current recommendations from the European Society for Medical Oncology and the American Society for Clinical Oncology advocating physical activity as a non-pharmacological strategy for cancer-related fatigue management . Prof. Eléonor Riesco and her team emphasize that even if the effects on fatigue were modest and observed at a single time point, the absence of harmful effects is clinically meaningful. Patients with metastatic cancer can engage in moderate-to-vigorous exercise close to chemotherapy treatment without fear of worsening their symptoms.
Translational Exercise Biomedicine
News article
Effects of aerobic exercise performed the day before chemotherapy on cancer-related fatigue and active behavior in advanced cancer patients: a randomized crossover pilot study
8-Jan-2026