EFFECT OF ANTIHYPERTENSIVE MEDICATION ON ENDURANCE EXERCISE CAPACITY IN HYPERTENSIVE SPORTSMEN

Beta-adrenoceptor blockade can influence exercise capacity negatively, but data on the effect of converting enzyme inhibition and of calcium entry blockade on exercise capacity in hypertensive sportsmen are scarce. This report deals with the effect of the various types of antihypertensive medication on endurance exercise capacity in 14 hypertensive sportsmen, aged 39 +/- 3 years and weighing 73 +/- 2 kg (mean +/- s.e.m.). The patients were treated for 3 weeks with either placebo, atenolol (50 mg/day) enalapril (10 mg/day) or verapamil (240 mg/day) following a double-blind randomized cross-over design. At the end of each treatment period, they performed an endurance exercise test on the bicycle until exhaustion at 70% of their previously determined exercise capacity. Venous blood was sampled before and after exercise. In comparison with placebo, total exercise duration was not affected by enalapril (-3 +/- 7%) or verapamil (-7 +/- 11%). During treatment with atenolol, two patients had to interrupt their intake of the beta-blocker because of side effects. In the 12 remaining subjects, exercise duration was significantly decreased by 38 +/- 12% (P < 0.01). Atenolol also induced decreases in plasma-free fatty acid concentration before and after exercise and an increase in potassium concentration after exercise, whereas enalapril and verapamil did not induce metabolic changes. During exercise, systolic blood pressure was decreased by atenolol (P < 0.001) and enalapril (P < 0.01) and diastolic blood pressure by enalapril (P < 0.001), verapamil (P < 0.05) and atenolol(P = 0.06). These data suggest that, in contrast to beta-adrenoceptor blockade, converting enzyme inhibition and calcium entry blockade do not affect endurance exercise capacity in hypertensive sportsmen.