The effect of physical training on hormonal status and exertional hormonal response in patients with chronic congestive heart failure.

BACKGROUND Physical training improves exercise capacity in patients with chronic heart failure. It decreases plasma noradrenaline at rest, which may be prognostically favourable. The effect on atrial natriuretic peptide, another prognostic factor, and on catabolic and anabolic hormones remains unknown. Furthermore, to our knowledge, the contribution of exertional hormonal responses to the improved exercise capacity has not been evaluated. METHODS 27 patients with stable chronic heart failure (New York Heart Association class II-III) were randomized to training (n=12) and control (n=15) groups. The training group exercised on a bicycle ergometer for 30 min three times a week for 3 months. The load corresponded to 50-60% of their peak oxygen consumption. For the next 3 months they exercised at home according to personal instructions. The control group did not change its physical activities. The levels of hormones regulating the cardiovascular system and metabolism were determined at rest and after graded maximal exercise and during exercise with constant submaximal workload. RESULTS Submaximal exercise capacity increased significantly and peak oxygen consumption tended to improve by 12% in the training group. The plasma noradrenaline at rest tended to decrease by 19%. The plasma level of N-terminal pro atrial natriuretic peptide did not change. Serum cortisol, a catabolic hormone, was normal at baseline and remained unchanged. The serum levels of anabolic hormones, growth hormone and insulin, as well as dehydroepiandrosteronesulfate and free testosterone were within a normal range at baseline. They were not altered by training. The dehydroepiandrosteronesulfate/cortisol, and the free testosterone/cortisol ratios, reflecting anabolic/catabolic balance, did not change, either. Training resulted in a higher peak noradrenaline response during graded maximal exercise. The rise in serum cortisol during exercise tended to attenuate. CONCLUSION Physical training, which improves exercise capacity, does not have an unfavourable effect on anabolic/catabolic balance or neurohumoral activation in patients with congestive heart failure. It decreases plasma noradrenaline at rest. Minor changes in hormonal responses during exercise emerged after physical training which unlikely contribute to the improved exercise capacity.