Effects of exercise training on aerobic and functional capacity of end-stage renal disease patients

Abstract

The aim was to assess the effects of exercise training on aerobic and functional capacity of patients with end-stage renal disease (ESRD). Patients completed an incremental exercise test on a cycle ergometer to determine VO2 peak and VO2 at ventilatory threshold (VT; V-slope). On a separate day they performed two constant load exercise tests on a cycle ergometer at 90% of VT and at a workload of 33 W, to determine VO2 kinetics. Functional capacity was assessed using measurements of sit-to-stands (STS-5, STS-60) and a walk test. Dialysis patients were randomly allocated to an exercise (ET: n=18, age=573 years) or control (C: n=15, age=505 years) group. The ET group participated in an exercise training programme involving cycling for 3 months. Repeated measures ANOVA revealed significant time by group interactions (P < 005) following training for VO2 peak (ET: 17 61 versus 199 63, C: 195 47 versus 188 49 ml kg min-1) and VO2-VT (ET: 107 35 versus 118 33, C:129 32 versus 119 35 ml kg min-1). VO2 kinetics remained unchanged in both groups at 90% -VT, but a trend (P=0059) towards faster kinetics at the 33 W was observed (ET: 496 195 versus 378 127, C: 428 13 versus 494 202 s). Significant time by group interactions (P < 005) were also observed for STS-5 (ET: 147 62 versus 110 33, C: 128 44 versus 127 48 s) and STS-60 measurements (ET: 212 72 versus 269 62, C: 237 68 versus 241 72). Three months of exercise rehabilitation significantly improves peak exercise capacity of patients with ESRD. Measurements of VO2 kinetics and functional capacity suggest that longer time might be needed to induce peripheral adaptations.