Onset of exercise training 14 days after uncomplicated myocardial infarction: a randomized controlled trial

BACKGROUND: Exercise training is an important part of cardiac rehabilitation to reduce morbidity and mortality. Low-intensity exercise training can start as soon as the myocardial infarction (MI) patient is stable. Our objective was to evaluate the effect of an early start of exercise training in MI patients. DESIGN: A randomized controlled trial. METHODS: Thirty-nine MI patients were randomized to either an early start of exercise training group (EG) or to a delayed start control group (CG). The EG participated in an outpatient low-intensity EG (phase 2a) two times a week for 4 weeks before entering ordinary exercise training of moderate-to-high intensity (phase 2b). CG entered phase 2b directly after 4 weeks of delay. Primary outcome measure was peak oxygen consumption (VO2peak), measured at baseline, after 4 weeks and after 16 weeks. Secondary outcome measure was health-related quality of life. RESULTS: VO2peak did not change from baseline to 4 weeks, either in EG [30.6+/-6.7 ml/kg/min vs. 30.7+/-6.2 ml/kg/min, not significant (NS)] or CG (29.8+/-6.1 ml/kg/min vs. 30.7+/-6.2 ml/kg/min, NS). After 16 weeks VO2peak increased in both groups to 33.1+/-7.1 ml/kg/min in EG (P<0.005) and 33.0 ml/kg/min+/-8.6 in CG (P<0.005), group differences NSH. Health-related quality of life increased in every domain but physical functioning for both groups (group differences NS). CONCLUSION: An early start of exercise training did not increase VO2peak compared to 4 weeks of delay. For low-risk patients with high motivation for exercise training, home-based walking is an option as a moderate start of cardiac rehabilitation the first weeks after MI.