Inclusion Criteria:  Children in this group will be healthy category according to CDC (Centers for Disease Control and Prevention) growth chart which ranged from BMI-for-age 5th to 85th percentiles . All children are normal &perform all activities of daily living They were able to understand and follow verbal commands and instructions included in the testing procedures.  Exclusion Criteria:  All of them could be part of recreational activities in their public schools but no competitive sports. Children who participated in any regular sport activities involving the lower extremities will be excluded. None of them had any surgical intervention . None of them had any history of other musculoskeletal deformities or neuromuscular disorders. They had neither visual, auditory defect.