Students of Sima Primary School practise football in Xiaoyi City, north China's Shanxi Province, May 17, 2016. Many village schools have set up more sports courses during these years as they are encouraged to add more physical education classes if conditions permit. A 2014 study found that 23 percent of Chinese boys under age 20 were overweight or obese, while the figure was 14 percent for girls. (Xinhua/Zhan Yan)