The effect of intradialytic combined exercise on hemodialysis efficiency in end-stage renal disease patients: a randomized-controlled trial

Purpose Insufficient dialysis is a difficult problem for patients undergoing hemodialysis, and causes cardiovascular complications and increases mortality. Increasing aerobic exercise and resistance exercise have been shown to be beneficial to physical fitness of patients undergoing hemodialysis, but a few studies have focused on combined exercise (combination of aerobic and resistance exercise training) and the interaction effect of combined exercise and intervention duration on hemodialysis efficiency. This study aimed to investigate the effects of 24-week combined exercise on hemodialysis efficiency, blood pressure, exercise capacity, and quality of life in patients undergoing hemodialysis. Methods In total, 47 eligible subjects were randomly allocated to exercise group and control group. The intervention group performed a 24-week, three times weekly, and moderate-intensity intradialytic combined exercise. Patients in the control group received usual care. The primary outcome was hemodialysis efficiency, which recorded every 4 weeks. Secondary outcomes included blood pressure, exercise capacity, and quality of life, measured at baseline and after 24 weeks of intervention. Results In intervention group, sp Kt/V significantly improved by 13.2%, and systolic blood pressure and diastolic blood pressure significantly decreased by 8.5 mmHg and 6.5 mmHg, respectively. The 6-min walking distance increased significantly by 43 m (9.8%), but there was no significant change in quality of life. Conclusion Combined exercise and intervention duration had an interaction effect on hemodialysis efficiency. Combined exercise improved blood pressure and physical fitness for patients undergoing hemodialysis, but did not affect quality of life. The extensive benefits of combined exercise provide evidence for the exercise development for patients undergoing hemodialysis.