6 patients with end-stage renal disease, hypertension and anemia were studied to determine the effect of endurance exercise training on their blood pressure. Initial exercise capacities were low (VO2 max = 18 +/- 2 ml/kg/min); however, their capacities increased (17 +/- 9%, p less than 0.05) after 14 +/- 5 months of training. This was associated with reductions in the antihypertensive medications in the 5 patients initially requiring them, and decreases in both predialysis systolic and diastolic blood pressures. There were significant increases in hemoglobin concentrations (7.3 +/- 0.4 to 9.8 +/- 0.9 g%) and hematocrit levels (23 +/- 2 to 30 +/- 3%) during training with no changes in body weights, interdialysis weight gains or serum albumin concentrations. 6 nonexercising dialysis patients had no changes in these same variables over the same period of time. These results suggest that endurance exercise training will reduce blood pressure and improve anemia in some hemodialysis patients.