http://medicalxpress.com/news/2012-10-foot-knee-hip-pain-problem.html

Foot, knee and hip pain a problem in obese children

"Obese children show diminished function, reduced psychosocial health (emotional, social and school functioning), and lower physical fitness compared with healthy weight peers. For these children, pain in the lower extremities is more common than pain in the upper extremities and back. However, it remains unclear whether pain interferes with physical fitness or physical activity levels in obese children. The researchers examined the medical charts of 175 obese children; of those, 51 reported lower extremity pain while 124 had no pain. The medical records included data on age, sex, race, puberty stage, lower extremity pain, physical function, psychosocial health and physical fitness."

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