Comparative analysis of cardiopulmonary responses of healthy sedentary men and men after acute myocardial infarction

The aim of this study was to assess the aerobic capacity of men after acute myocardial infarction (G-AMI) and of healthy sedentary men (G-C) at the anaerobic threshold (AT) and at the peak of the exercise (up to physical exhaustion) during a ramp-type ergospirometric test (R-ET). Methods: 22 volunteers divided into two groups: G-AMI (n=10), 55.6 c 9.7 years old, undergoing b-blocking therapy (atenolol, dosage 46 c 9.4 mg/day), Killip classification grade I, and G-C (n=12), 53.3 c 3.2 years old. The G-C subjects took no type of medication. Experimental protocol: R-ET, with power increments of 10W/min for the G-AMI and of 15W/min for the G-C. The evaluated variables were: heart rate (HR), ventilatory and metabolic, recorded breath-by-breath using an ergospirometer (CPX/D MedGrafics - Breeze, St Paul, Minnesota, USA). Statistical Analysis: Mann-Whitney tests a = 5%. The power, cardiovascular, ventilatory and metabolic variables obtained from the R-ET at the peak of the exercise, for G-AMI and G-C, presented a statistically significant difference (p0.05). Conclusion: The lower aerobic capacity at the peak of the exercise can be attributed to the use of b-blocking therapy and to prolonged bed rest.