Comparison of intradialytic continuous and interval training on hemodynamics and dialysis adequacy: A crossover randomized controlled trial

Aim: Circulating blood volume (BV) during exercise changes depending on the intensity and duration, and post-exercise hypotension is observed after continuous exercise. We investigated the safety and efficacy of both interval and continuous IDE at anaerobic threshold (AT) levels with respect to hemodynamic stability and dialysis efficiency.Methods: In this crossover randomized controlled trial, 16 patients on haemodialysis were subjected to three trial arms, including non-IDE, interval-IDE, and continuous-IDE arms. Systolic blood pressure (SBP), BV, and ultraviolet absorbance - an indicator of dialysis efficiency - were continuously measured, and each change was compared between the three arms by two-way analysis of variance.Results: Continuous IDE decreased SBP from post-exercise to the end of dialysis compared with baseline (pre 142.8 +/- 19.0 vs. post 127.5 +/- 24.5 mmHg, p = .02), whereas interval IDE maintained better SBP levels post-exercise (pre 139.9 +/- 17.1 vs. post 140.1 +/- 15.8 mmHg, p = 1.0) than continuous IDE (non-IDE 133.2 +/- 19.9 vs. interval 140.1 +/- 15.8 vs. continuous 127.5 +/- 24.5 mmHg, p = .04). Moreover, interval IDE caused less tiredness and few symptoms (p < .05), despite reaching higher intensity than continuous IDE (p = .001). The BV of each IDE arm decreased during exercise and recovered post-exercise to the same level as non-IDE. Ultraviolet absorbance was not different between each arm (p = .16).Conclusion: AT-level interval IDE maintains better hemodynamic stability from post-exercise to the end of dialysis and may represent a novel approach that can be effectively performed with fewer symptoms.