Intradialytic Cardiovascular Exercise Training Alters Redox Status, Reduces Inflammation and Improves Physical Performance in End Stage Renal Disease Patients under Hemodialysis

Introduction: Redox status (RS) perturbations and inflammation are fundamental features of chronic kidney disease (CKD) that are substantially exacerbated in end-stage renal disease (ESRD). Aim: This study aimed at investigating the efficacy of a 6-month intradialytic exercise training program on RS, inflammation and physical performance in patients with ESRD. Materials and Methods: Twenty hemodialysis (HD) patients (17 males, 3 females) were randomly assigned to either an intradialytic training (bedside cycling) group (TR; n = 10) or a control group (CON; n = 10) for 6 months. Anthropometrics [body mass and height, body mass index (BMI), body composition], physical performance (VO2peak), functional capacity [North Staffordshire Royal Infirmary (NSRI) walk test, sit-to-stand test (STS-60)], quality of life [(short form-36 (SF-36)] as well as RS [thiobarbituric acid reactive substances (TBARS), protein carbonyls (PC), reduced (GSH) and oxidized (GSSG) glutathione, GSH/GSSG ratio, total antioxidant capacity (TAC), catalase activity (CAT)] and high-sensitivity C-reactive protein (hs-CRP) were assessed at baseline and after the 6-month intervention. Results: Peak oxygen consumption (VO2peak) increased by 15% only in TR (p < 0.01). Performance in NSRI, STS-60 and SF-36 improved by 4–13% only in TR (p < 0.01). Exercise training reduced TBARS (by 28%), PC (by 31%) and hs-CRP (by 15%), and elevated GSH (by 52%), GSH/GSSG ratio (by 51%), TAC (by 59%) and CAT (by 15%) (p < 0.01). Conclusion: These findings suggest that engagement in chronic intradialytic cardiovascular exercise alters RS, reduces inflammation and improves performance in patients with ESRD. Future studies are required to examine this scenario using a larger sample size, to allow for the extraction of safe conclusions.