Chronic kidney disease (CKD) is directly influenced by the deleterious effects of systemic inflammation and oxidative stress. The vascular endothelium may transiently respond to aerobic exercise and improve post-exercise vascular renal function in moderate stages of CKD. Brachial artery flow-mediated dilation (FMD) is a nitric-oxide-dependent measure of endothelial function that is transiently potentiated by exercise. The purpose of the study was to determine the acute influence of a single bout of high-intensity interval exercise (HIIE) or steady-state moderate-intensity exercise (SSE) on endothelial dysfunction in moderate stages of CKD. Twenty participants (n = 6 men; n = 14 women) completed 30 min of SSE (65%) and HIIE (90:20%) of VO2reserve in a randomized crossover design. FMD measurements and blood samples were obtained before, 1 h, and 24 h post-exercise. FMD responses were augmented 1 h post-exercise in both conditions (p < 0.005). Relative to pre-exercise measures, total antioxidant capacity increased by 4.3% 24 h post-exercise (p = 0.012), while paraoxonase-1 was maintained 1 h and elevated by 6.1% 24 h after SSE, but not HIIE (p = 0.035). In summary, FMD can be augmented by a single episode of either HIIE or SSE in moderate stages of CKD. Modest improvements were observed in antioxidant analytes, and markers of oxidative stress were blunted in response to either SSE or HIIE.
Keywords: antioxidants; flow-mediated dilation; high-intensity interval exercise; steady-state exercise.