Pilot study of fitness training and exercise testing in polyarticular childhood arthritis

Objective. To 1) assess the safety and feasibility of laboratory-based exercise testing in juvenile idiopathic arthritis (JIA), 2) test the safety and feasibility of a 3-month exercise program in JIA, 3) assess pain during exercise in JIA, 4) compare ratings of perceived effort (RPE) with heart rate (HR) achieved, and 5) estimate the training effect on metabolic efficiency of gait as measured by submaximal exercise testing. Methods. Nine children with JIA were enrolled in a 12-week circuit training program involving pool, stationary bicycle, treadmill, and Fitball. They underwent formal exercise testing before and after the program, underwent a full joint assessment, were administered the Childhood Health Assessment Questionnaire and juvenile Arthritis Functional Status Index, and were assessed for overall quality of life and health-related quality of life. A visual analog scale was used to assess pain during testing and training, and the Borg scale was used to measure RPE. Results. Children with JIA were able to participate in exercise testing without any significant problems. Children with severe hip disease dropped out of the exercise program due to pain during the exercise sessions and worsened arthritis symptoms. Target HR was achieved and correlated with RPE in the bicycle and treadmill sessions. Submaximal exercise testing showed an improvement with a small to moderate effect size. Conclusion. This study suggests that it is safe, feasible, and acceptable for children with arthritis, in the absence of severe hip involvement, to participate in formal exercise testing and structured fitness programs.