Background: Prescription of endurance training and documentation of its efficacy in patients with chronic heart failure (CHF) is usually done with reference to maximal ergometric measurements which are subject to form on the day changes and motivational influences. However, the use of submaximal parameters might represent an alternative approach.
Methods: This was tested in 54 patients with CHF (57 +/- 10 years, NYHA II: n = 40; NYHA III: n = 14) who were randomized into training (T; n = 26) or control group (CO; n = 28). Training consisted of 45 minutes cycling at an intensity corresponding to the anaerobic threshold (AT) and was conducted for 12 weeks, 4 to 5 times per week. Cardiorespiratory exercise testing was done before and after the experimental phase. Changes in well-being were investigated using a 5-point Likert scale.
Results: A significant rightward shift in the heart rate curve was demonstrated in T compared with CO (P = .01; T: decrease in resting heart rate by 8 per minute, during exercise by 7 to 11/min; CO: -1 and -1 to -3 per minute, respectively). Anaerobic threshold increased significantly by 11.6% in T (+0.11 +/- 0.11 L min(-1) oxygen uptake) compared with CO (-0.02 +/- 0.10 L min(-1)). Positive changes in well-being were significantly larger in T (P < .01).
Conclusions: In patients with CHF, training can be prescribed and its efficacy can be evaluated by the exclusive use of submaximal parameters. Anaerobic threshold represents an appropriate training intensity in this population.