The Impact of Physical Exercise on Posttransplant Outcomes in Kidney Transplant Recipients: A Systematic Review and Meta-analysis

Kidney transplantation is the preferred treatment for end-stage renal disease. However, recipients remain at risk for cardiovascular complications, allograft rejection, and delayed graft function. Physical inactivity contributes to reduced quality of life, increased cardiovascular risk, and higher mortality. This systematic review and meta-analysis aimed to evaluate the effects of exercise interventions on kidney transplant recipients, focusing on outcomes such as peak oxygen uptake (VO₂ peak), six-minute walk test (6MWT) or six-minute walk distance (6MWD), creatinine, estimated glomerular filtration rate (eGFR), urea, interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α). A systematic search was conducted on PubMed, Scopus, Web of Science, and Cochrane for randomized controlled trials (RCTs) published between January 2015 and January 2025 that evaluated the effects of exercise interventions in kidney transplant recipients. Eligibility was determined using a modified PICO framework, and risk of bias was assessed with the RoB-2 tool. Eleven studies comprising 628 adult participants met the inclusion criteria and were included in the meta-analysis. Exercise significantly improved 6MWT/6MWD (mean difference [MD]: 68.71; P = 0.003) and VO₂ peak (MD: 2.64; P = 0.0010), and reduced levels of TNF-α (MD: −5.33; P = 0.02), creatinine (MD: −0.25; P = 0.0010), and urea (MD: −24.54; P = 0.0008). No significant changes were found for IL-6 and eGFR. These findings suggest that exercise after kidney transplantation improves cardiovascular performance and some aspects of renal function, as reflected by better 6MWT, VO₂ peak, and reduced creatinine and urea. It also lowers TNF-α, indicating reduced inflammation. However, the effects on IL-6 and eGFR remain inconclusive.