Effects of exercise training on exercise aerobic capacity and quality of life in hemodialysis patients.

BACKGROUND: Physical and aerobic capacity are extremely limited in dialysis patients, but it is uncertain whether or not exercise training is safe or has beneficial effects. This study aimed to assess the effects of exercise training on functional capacity and quality of life of hemodialysis patients.

METHODS: Ten hemodialysis patients (7 men, 3 women, aged 37 +/- 7 years) free from severe comorbidities were recruited. They underwent training sessions (up to 90 minutes of submaximal exercise) twice a week, on nondialysis days, for 12 months. At baseline and after the physical training program, all patients underwent biochemistry, cardiopulmonary exercise test, echocardiography and a self-rated health test (SF-36).

RESULTS: At baseline, dialysis patients showed impaired VO2 uptake (20.6 +/- 5.0 ml/kg/min vs. 34.2 +/- 6.0 ml/kg/min, p<0.001) and peak working capacity (115 +/- 36 W vs. 192 +/- 46.7 W, p<0.001) compared with normal controls. Following the training program, both peak VO2 (20.4 +/- 4.9 ml/kg/min vs. 25.1 +/- 6.5 ml/kg/min, p<0.05), VO2 at anaerobic threshold (12.8 +/- 1.9 ml/kg/min vs. 15.1 +/- 3.8 ml/kg/min, p<0.05), peak working capacity (113 +/- 33 W vs. 134 +/- 37 W, p<0.01) and SF-36 scores improved. No side effects related to intervention occurred.

CONCLUSIONS: Dialysis patients showed impaired muscular exercise capacity, but 12 months of moderate exercise training was able to improve their physical function, aerobic capacity and quality of life. Our study suggests that mild, regular physical activity should be recommended and encouraged as an important aspect of the care of selected dialysis patients.