Reduced exercise capacity can predispose solid organ transplant (SOT) recipients to higher risk of diabetes, cardiovascular complications, and mortality and impact their quality of life. This systematic review and meta-analysis investigated the effects of exercise training (versus no training) in adult SOT recipients. We conducted an electronic search of randomized controlled trials reporting on exercise interventions in SOT recipients. Primary outcomes were exercise capacity, quadriceps muscle strength, and health-related quality of life (HRQoL). Twenty-nine articles met the inclusion criteria. In 24 studies, there were either high risk of bias or some concerns about the potential risk of bias. There was an increase in exercise capacity (VO2 peak) (SMD: 0.40; 95%CI 0.22–0.57; P = 0.0) and quadriceps muscle strength (SMD: 0.38; 95%CI 0.16–0.60; P = 0.001) in the exercise vs control groups. There were also improvements in several domains of the SF-36. Diastolic blood pressure improved in the exercise group compared to controls (SMD:
0.22; 95%CI
0.41–0.03; P = 0.02). Despite the considerable variation in exercise training characteristics and high risk of bias in the included studies, exercise training improved maximal exercise capacity, quadriceps muscle strength, HRQoL, and diastolic blood pressure and should be an essential part of the post-transplant care.