A boy struggles while doing a sit-up at a summer camp to tackle child obesity in Zhengzhou, Henan province, on July 14, 2013. The 20-day "fat camp", organized by Zhengzhou Children's Hospital, aims at helping overweight children aged 8-14 to reduce weight and lead a healthy lifestyle. [Photo by Zhang Tao/Asianewsphoto]

Children warm up before daily fat-burning exercises at a summer camp which aims to help obese children lose weight in Zhengzhou, Henan province, on July 14, 2103. [Photo by Zhang Tao/Asianewsphoto]