ObjectiveTo develop a systematic review of physical activity benefits for children and adolescents with intellectual and developmental disabilities and the PICO framework based on the International Classification of Functioning, Disability and Health (ICF), and to explore the health benefits of physical activity for children and adolescents with intellectual and developmental disabilities. MethodsA systematic analysis of health and functional status, physical activity interventions, and physical activity benefits in children and adolescents with intellectual and developmental disabilities was conducted using ICF. Databases such as PubMed, Embase, Web of Scienc, and CNKI were searched to collect published randomized controlled trials on health and functional outcomes of physical activity participation in children and adolescents with intellectual and developmental disabilities from establishment to November, 2022 for a systematic review. ResultsTen randomized controlled trials from five countries were finally included, involving 289 participants (five to 18 years old). The literatures were mainly from the fields of cognitive neuroscience, intellectual and developmental disabilities, physical activity and exercise rehabilitation, and were published mainly after 2013. The quality of the included literatures was evaluated using the Physiotherapy Evidence Database (PEDro) scale with a mean score of 7.6. Health-related conditions in children and adolescents with intellectual and developmental disabilities included Down syndrome, dyskinetic cerebral palsy, autism spectrum disorders, fragile X syndrome, and patients with mild and moderate intellectual and developmental disabilities. Physical activity interventions for children and adolescents with intellectual and developmental disabilities were focused on schools, rehabilitation centers, gymnasiums, laboratories, and research institutions and were usually in the form of motor rehabilitation, physical activity and physical education programs. The physical fitness focused on vestibular stimulation training, inversion exercises and core muscle training; the sports events included soccer training, bicycle riding, etc. The frequency of physical activity was one to seven times per week, with moderate intensity and a duration of four weeks to 1.5 years. The health benefits of physical activity were divided into three levels. At the physical function level, physical activity could significantly improve the muscle strength and endurance, aerobic capacity, lower limb motor stability and balance, promote perceptual-motor coordination, reduce psychomotor error rates, and improve perceptual-motor function and overall motor execution. At the activity and behavioral health level, physical activity could significantly improve the concentration time in movement, improve single-leg stance time and core strength in the lumbar and abdominal areas to improve postural control and mobility, involving performance levels in activities such as lying and rolling, sitting, kneeling, standing, walking, running and jumping. At the quality of life and well-being level, physical activity intervention could increase their fun experiences and activity participation time, etc. ConclusionThe health conditions of children and adolescents with intellectual and developmental disabilities are mainly involved in Down syndrome, dyskinetic cerebral palsy, autism spectrum disorder, and fragile X chromosome. The physical activity intervention program is characterized by a predominantly physical activity program oriented and skill oriented. The health and functional benefits of physical activity participation in children and adolescents are mainly characterized by improved neuromusculoskeletal and motor-related functions, enhanced activity and participation levels, reduced sedentary behavior, increased participation in daily activities, and improved quality of life and well-being.