Effect of Aerobic Training on Sleep Problems and Pulmonary Functions in Children With Down Syndrome

Inclusion Criteria: * Children with Down syndrome (trisomy 21). * Their ages range from 7 to 12 years old. * Both sexes will be included. * Children should be able to understand and follow simple verbal commands or instructions (intelligence quotient (IQ) range: 50-70). * Children should be able to walk independently. * Their total scores on the Arabic version of the Children's Sleep Habits Questionnaire (CSHQ) equal 41 or higher. Exclusion Criteria: Children will be excluded from the study if they: * Have visual or hearing defects. * Have spinal abnormality such as kyphosis and scoliosis. * Have history of pulmonary infection and surgery of thoracic and abdominal region within the past 6 months. * Play any specific sport or exercises. * Have physical activity restrictions. * Have musculoskeletal disorder. * Take medications known to affect sleep.