A randomized dose-response trial of aerobic exercise and health-related quality of life in colon cancer survivors

Objective: To examine the dose-response effects of aerobic exercise on health-related quality of life (HRQoL) among colon cancer survivors. Methods: Thirty-nine stage I to III colon cancer survivors were randomized to 1 of 3 groups: usual-care control, 150 min·wk ⁻¹ of aerobic exercise (low-dose) and 300 min·wk ⁻¹ of aerobic exercise (high-dose) for 6 months. HRQoL outcomes included the Short Form (SF)-36 physical and mental component summary, Functional Assessment of Cancer Therapy-Colorectal, Pittsburgh Sleep Quality Index, Fear of Cancer Recurrence Inventory, Fatigue Symptom Inventory, and North Central Cancer Treatment Group bowel function questionnaire, assessed at baseline and post intervention. The primary hypothesis was that exercise would improve HRQoL outcomes in a dose-response fashion, such that high-dose aerobic exercise would yield the largest improvements in HRQoL outcomes. Results: Over 6 months, the low-dose group completed 141 ± 10 min·wk ⁻¹ of aerobic exercise, and the high-dose group completed 247 ± 11 min·wk ⁻¹ of aerobic exercise. Over 6 months, exercise improved the physical component summary score of the SF-36 (P _trend  = 0.002), the Functional Assessment of Cancer Therapy-Colorectal (P _trend  = 0.025), the Pittsburgh Sleep Quality Index (P _trend  = 0.049), and the Fatigue Symptom Inventory (P _trend  = 0.045) in a dose-response fashion. Between-group standardized mean difference effects sizes for the above-described findings were small to moderate in magnitude (0.35–0.75). No dose-response effects were observed for the mental component summary score of the SF-36, the Fear of Cancer Recurrence Inventory, or bowel function. Conclusion: Higher doses of aerobic exercise, up to 300 min·wk ⁻¹ , improve multiple HRQoL outcomes among stage I to III colon cancer survivors. These findings provide evidence that aerobic exercise may provide multiple health benefits for colon cancer survivors.