ABSTRACT OBJECTIVE: To compare the efficacy of a cycle ergometer-based exercise program to a standard protocol on the increment of the maximum distance walked during the six-minute walk test in the postoperative rehabilitation of patients submitted to coronary artery bypass grafting. METHODS: A controlled clinical trial pilot, blinded to the outcome, enrolled subjects who underwent coronary artery bypass grafting in a hospital from Southern Brazil. Subjects were designated for the standard physical rehabilitation protocol or to an alternative cycle ergometer-based protocol through simple random sampling. The primary outcome was the difference in the maximum distance walked in the six-minute walk test before and after the allocated intervention. RESULTS: Twenty-four patients were included in the analysis, 10 in the standard protocol and 14 in the alternative protocol group. There was an increment in the maximum distance walked in both groups, and borderline superiority in the intervention group comparing to the control group (312.2vs. 249.7; P=0.06). CONCLUSION: There was an increase in the maximum distance walked in the alternative protocol compared to the standard protocol. Thus, it is postulated that the use of a cycle ergometer can be included in physical rehabilitation in the hospital phase of postoperative coronary artery bypass grafting. However, randomized studies with larger sample size should be conducted to assess the significance of these findings.