Using cardiopulmonary stress testing in 76 lean and 99 obese coronary patients, we demonstrated significant improvements in both groups for anaerobic threshold, peak aerobic capacity (VO2), peak VO2 corrected for lean body mass, and work efficiency. Although anaerobic threshold and peak VO2 are adequate to describe exercise capacity in lean patients, baseline and post-training data are best exemplified by peak VO2 corrected for lean body mass and work efficiency in obese coronary patients.