BACKGROUND Intradialytic exercise has been poorly investigated in pediatric patients on chronic hemodialysis (HD). The aim of this study was to assess the acceptability, safety and efficacy of intradialytic exercise in children and young adults on HD. METHODS The intradialytic exercise program consisted of 30-min sessions of intra-HD exercise using a cycloergometer two to three times a week for 3 months. Study endpoints were the 6-min walking test (6MWT) distances, lung function, number of stands in the chair test, lower extremity strength (LES), anthropometry, dietary intake, dialysis adequacy, incidence of symptomatic sessions, biochemistry and left ventricular mass index. RESULTS Ten pediatric patients with a median age of 15.3 (range 9.1-24.2) years were enrolled. Two of these underwent kidney transplantation; the remaining eight completed the study and adapted well to the exercise program. At the end of the 3-month study period, all patients had significantly improved results for the 6MWT (+4.9 %; p < 0.05), chair test (+19 %; p < 0.05) and LES (+29.3 %; p < 0.05). Pre-HD albumin, creatinine and total protein levels and post-HD creatinine levels had also significantly improved. The incidence of symptomatic sessions did not increase during the study period. No adverse events occurred. CONCLUSIONS Based on our results, we conclude that a 30-min exercise program of intradialytic cycling is feasible for the majority of pediatric patients on chronic HD and will be well accepted. Such an exercise program can lead to a significant improvement in the exercise capacity of this patient population.