Effects of different training modalities on circulating anabolic/catabolic markers in chronic heart failure.
- Competence Center for Methodology and Statistics
BACKGROUND: Muscle wasting in chronic heart failure (CHF) is a result of increased catabolism induced by proinflammatory cytokines like tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6), and decreased anabolism due to alterations in the insulin-like growth factor 1 (IGF-1)/growth hormone (GH) axis. The goal of this study was to analyze the effects of 3 different training modalities (endurance training, strength training, and combined strength and endurance training [CT]) on circulating cytokines, IGF-1, and GH levels. METHODS: Patients with CHF (N = 45), NYHA class II-III, left ventricular ejection fraction < 35%, were randomly assigned to 1 of 3 training modalities. They trained for 40 sessions, 3 times weekly. Fifteen CHF patients served as a control group. Blood samples were collected at baseline and 48 hours after the last training session. RESULTS: There was a significant decrease in circulating IL-6 with all 3 training modalities. Tumor necrosis factor alpha levels decreased in the training groups and reached statistical significance for the CT group. No change was observed in the control group. There was no difference between the 4 groups. When comparing all trained patients with the control group, the decrease in IL-6 was significant. Concerning IGF-1 and GH, there was no change with training and no change in the control group. CONCLUSION: Exercise training has no effects on circulating IGF-1 and GH. The decreases in cytokines are evident only when all trained patients are compared with the control group, independently of the modality of training intervention.