Early programmes of high and low intensity exercise and quality of life after acute myocardial infarction

OBJECTIVE--To determine whether a group programme of light exercise could improve quality of life in patients after acute myocardial infarction to the same extent as a high intensity exercise training programme. SETTING--Australian teaching hospital. PATIENTS--224 men from a consecutive series of 339 men under 70 admitted to a coronary care unit with transmural acute myocardial infarction. INTERVENTION--Patients were randomly allocated in hospital to a group programme lasting eight weeks of either high intensity exercise training or light exercise. MAIN OUTCOME MEASURES--Physical working capacity based on metabolic equivalents achieved from treadmill exercise tests at entry, after 11 weeks, and after one year. Quality of life based on self report scores of anxiety, depression, denial, and wellbeing and interview assessments of activities and psychosocial adjustment at entry, after four months, and after one year. RESULTS--The two groups were well matched at entry. At 11 weeks the mean results of treadmill testing were 10.7 (95% confidence interval 10.20 to 11.20) metabolic equivalents for exercise training and 9.7 (9.26 to 10.14) for light exercise (t = 2.85, df = 181, p = 0.005). Apart from this small temporary benefit in mean physical working capacity, there were no significant differences between groups. Improvement in occupational adjustment score from baseline to four months was greater after exercise training than after light exercise, but at one year repeated measures analysis of variance showed no significant effects of treatment or interaction between treatment and time point. CONCLUSION--The effects on quality of life of a low cost programme of light exercise are similar to those obtained from a high intensity exercise training programme.