Background Early exercise after coronary stenting is considered to have a risk of stent thrombosis (ST). We investigate the safety of submaximal exercise training based on the Borg scale from the next day after coronary stenting. Methods We enrolled 2351 patients who underwent successful coronary stenting. They were divided into early exercise training (EET) group (n=865) and control group (n=1486). Submaximal exercise training based on the Borg scale was performed on the next day after coronary stenting and same degree exercise was continued more than two times a week after discharge. Primary endpoint was the incidence of ST. Secondary endpoint was major adverse cardiovascular event (death, myocardial infarction, and stroke), incidence of postoperative complications, and rate of exercise continuation. Results Exercise training was performed in 800 (92.5%) patients. No serious complication developed during and after exercise. Clinical follow-up data were obtained in 99% patients. At 30 days, there was no significant difference in the incidence of ST (0.58 vs. 0.47%, P=0.73), major adverse cardiovascular event (1.4 vs. 1.3%, P=0.72), and complication rate (6.9 vs. 7.3%, P=0.72). No exercise-related ST was found in either group. The rate of exercise continuation was significantly higher in the EET group (49.3 vs. 28.3%, P < 0.001). Conclusion EET up to submaximal level based on the Borg scale from the day after elective coronary stenting does not increase the incidence of ST or postoperative complications. Eur J Cardiovasc Prev Rehabil 17: 230-234 (C) 2010 The European Society of Cardiology