Feasibility and benefits of exercise training in patients on maintenance dialysis

Fourteen of 174 patients receiving maintenance dialysis volunteered to participate in a 12-week exercise conditioning program. Seven patients attended more than 50% (range, 55 to 75%) of the sessions held three times each week. These seven patients achieved a 42% (P less than 0.05) improvement in work capacity as assessed by maximal oxygen consumption during treadmill testing. No changes occurred in psychologic functioning, blood pressure control, hematocrit, or left ventricular ejection fraction. Seven patients attended fewer than half of the sessions (range, 1 to 38%) and did not demonstrate improved exercise capacity. Psychologic testing at entry revealed that those who did not attend regularly had higher scores for hostility, anxiety, and depression as compared to those patients who completed the program. No other clinical variables distinguished those who had good attendance records from those who did not. We conclude that exercise conditioning can improve physical work capacity in patients with chronic renal failure who are receiving maintenance dialysis treatment. Despite this potential benefit, the impact of exercise conditioning programs such as this may be limited because only a small portion of patients on maintenance dialysis are able or willing to participate to an extent sufficient to induce physiological changes.