The Effect of Interdialytic Combined Resistance and Aerobic Exercise Training on Health Related Outcomes in Chronic Hemodialysis Patients: The Tunisian Randomized Controlled Study

Abstract

Background: Tunisia has the highest prevalence of hemodialysis patients compared to the other countries in North Africa. Dialysis centers rarely offer an exercise program to prevent physiological and psychological dialysis therapy-related alterations in chronic hemodialysis patients. Aim: To examine the effect of combined endurance-resistance training program on physiological and psychological outcomes in patients undergoing hemodialysis. Methods: We designed a single blinded, randomized, controlled study for a period of 4 months. Patients were randomized to intervention group or control group. Intervention group patients received 4 training sessions per week, held on non-hemodialysis days for a period of 4 months, whereas control group patients continued their regular lifestyle practice without direct intervention from the personnel of this investigation. Patients were evaluated at baseline (initial assessment) and after the four-month study period (final assessment) by the same investigator blinded to treatment group assignment using physical, physiological, and psychological measurements. Results: Compared with control group, intervention group showed significant improvement in physical performance during the sit-to-stand-to-sit tests (STS-10: -16.2%, ES = -1.65; STS-60: +23.43%, ES = 1.18), handgrip force task (+23.54%, ES = 1.16), timed up and go test (-13.86%, ES = -1.13), and 6-min walk test (+15.94%, ES = 2.09). Likewise, mini nutritional assessment long form scores after intervention period were significantly higher in the intervention group compared to the control group (ES = 1.43). Physical and mental component scores of SF-36 questionnaire increased significantly in the intervention group (ES = 1.10 and ES = 2.06, respectively), whereas hospital anxiety and depression scale scores decreased significantly (ES = -1.65 and ES = -2.72, respectively). Regarding biological parameters, intervention group displayed improvement in systolic and diastolic blood pressures (ES = -2.77 and ES = -0.87, respectively), HDL-cholesterol, LDL-cholesterol, and triglycerides systematic levels (ES = 1.15, ES = -0.98, and ES = -1.01, respectively); however no significant effect of intervention period was observed on C-reactive protein, hemoglobin, albumin, and total cholesterol levels (P > 0.05). Conclusion: The current study showed that combined endurance-resistance training program had a beneficial effect on physical capacity and quality of life in chronic hemodialysis patients.

Keywords: exercise; hemodialysis; physical capacity; physiological responses; psychological responses.

Figure 1

Flow diagram of the progress through the study phases.

Figure 2

Relative differences between the intervention group and the control group for the 6-min walk test (6MWT), timed up and go test (TUG), handgrip force, and sit-to-stand-to-sit tests (STS-10 and STS-60). Bars indicate uncertainty in the true mean changes with 95% confidence intervals. Trivial areas were calculated based on the smallest worthwhile change (SWC).

Figure 3

Physical component scores (A), mental component scores (B), anxiety scores (C) and depression scores (D) at initial and final assessments in both groups. ^*Significantly different from initial assessment (P < 0.01). ^§Significantly different from control group (P < 0.01). Values are means ± SD.