Therapeutic benefits of exercise training for hemodialysis patients

Twenty-five hemodialysis patients were randomized into comparable exercising (E, N = 14) and sedentary control (N = 11) groups. After baseline testing, training was 3 to 5 times weekly for a mean of 12 ± 4 (SD) months. Maximal aerobic capacity increased 21% (P<0.01), and the durations for the graded exercise stress test improved 19% (P<0.01) in E, but did not change in controls (8 ± 4 months). Declining blood pressures in 8 hypertensive E led to reductions in antihypertensive medications; no change occurred in 9 hypertensive controls. Exercise lowered plasma total triglyceride levels 33% (280 ± 258 to 175 ± 95 mg/d;. P<0.01), but no change occurred in total and low-density lipoprotein cholesterol concentrations. High-density lipoprotein cholesterol levels rose 16% in E (31 ± 9 to 36 ± 12 mg/dl; P<0.02), but did not change in controls. An increase in the affinity of insulin for receptors on mononuclear cells was associated with a 20% decrease in fasting plasma insulin levels (24 ± 7 to 19 ± 2 μU/ml, N = 8; P<0.05) and a 42% improvement in glucose disappearance rates (1.9 ± 1.0 to 2.6 ± 1.2% per min, N = 6) in E. There were no changes in the body weights or diets of the patients. A 27% increase in red blood cell mass (P<0.02) with no change in plasma volume resulted in a 27% increase in hematocrit (24 ± 3% to 31 ± 5%, P<0.01) and a 20% increase in hemoglobin (8 ± 1 to 10 ± 2 g/dl;, P<0.01) in E. Reported levels of depression decreased in E, but other psychological parameters did not change. In controls, however, levels of hostility, anxiety, and depression worsened and there was a deterioration in the frequency of pleasurable events. Thus, exercise training seems to have beneficial metabolic and psychologic effects in some hemodialysis patients, and should be considered as a therapeutic modality for their medical management and rehabilitation.