Abstract

Beta-receptor antagonists lower exercise heart rate and cardiac output, and can thus be expected to interfere with oxygen transport, and hence physical performance, particularly at higher levels of activity. Therefore, the effects of a 4-week and 15-month treatment period with the beta 1-selective receptor blocker acebutolol (500 mg daily) on oxygen uptake and plasma catecholamines during submaximal steady-state and maximal exercise and on maximal work load were studied in eight WHO stage 1 hypertensive men (mean age 36.4 years). Oxygen uptake, ventilation, and plasma noradrenaline, adrenaline, and dopamine concentrations during steady-state exercise were not significantly different from control conditions either after 4 weeks or after 15 months of receptor blockade, although heart rates were significantly. Since beta 1selective receptor blockers do not affect maximal oxygen uptake and maximal work capacity after long-term treatment, they appear preferable for patients taking part in preventive and rehabilitative training programs. Verf.-Referat