OBJECTIVE To investigate the feasibility of a pragmatic lifestyle intervention in patients who had recently completed surgery and chemotherapy for colon cancer and to obtain preliminary data of its impact on important health outcomes. DESIGN A prospective, randomized, controlled pilot trial. SETTING University rehabilitation facility. PARTICIPANTS Eighteen (N=18) colon cancer survivors (mean age=69y; range, 52-80y), Dukes stage A to C. INTERVENTIONS Participants were randomized 6 to 24 months postoperatively to either a 12-week program of combined exercise and dietary advice or standard treatment. MAIN OUTCOME MEASURES Exercise and dietary behavior, fatigue, health-related quality of life (QOL), aerobic exercise tolerance, functional capacity, muscle strength, and anthropometery were assessed at baseline and immediately after the intervention. RESULTS Adherences to supervised and independent exercise during the intervention were 90% and 94%, respectively, and there was low attrition (6%). The lifestyle intervention elicited improvements in exercise behavior (P=.068), fatigue (P=.005), aerobic exercise tolerance (P=.010), chair sit-to-stand performance (P=.003), and waist-to-hip ratio (P=.002). A positive change in dietary fiber intake (P=.044) was also observed in the intervention group. No change in QOL was observed (P=.795). CONCLUSIONS These preliminary results suggest that a pragmatic lifestyle intervention implemented 6 to 24 months after primary treatment for colon cancer was feasible. We observed a significant impact on dietary behavior, fatigue, aerobic exercise tolerance, functional capacity, and waist-to-hip ratio. These findings need to be confirmed with a larger-scale definitive randomized controlled trial.