A clinical evaluation of VO2 kinetics in kidney transplant recipients

Purpose Aerobic exercise capacity is reduced in patients with chronic kidney disease, partly due to alterations at the muscular and microvascular level. This study evaluated oxygen uptake (VO 2 ) kinetics as indicator of muscular oxidative metabolism in a population of Kidney Transplant Recipients (KTRs). Methods Two groups of KTRs enrolled 3 ( n = 21) and 12 months ( n = 14) after transplantation and a control group of healthy young adults ( n = 16) underwent cardiopulmonary exercise testing on cycle-ergometer. The protocol consisted in two subsequent constant, moderate-load exercise phases with a final incremental test until exhaustion. Results The time constant of VO 2 kinetics was slower in KTRs at 3 and 12 months after transplantation compared to controls (50.4 ± 13.1 s and 43.8 ± 11.6 s vs 28.9 ± 8.4 s, respectively; P