Children ride at the Balance Bike Riders' Asian Championship held in Haikou, south China's Hainan Province, Aug. 17, 2019. (Xinhua/Guo Cheng)

Children ride at the Balance Bike Riders' Asian Championship held in Haikou, south China's Hainan Province, Aug. 17, 2019. (Xinhua/Guo Cheng)

Children prepare to compete at the Balance Bike Riders' Asian Championship held in Haikou, south China's Hainan Province, Aug. 17, 2019. (Xinhua/Guo Cheng)

A child rides at the Balance Bike Riders' Asian Championship held in Haikou, south China's Hainan Province, Aug. 17, 2019. (Xinhua/Guo Cheng)

A child rides at the Balance Bike Riders' Asian Championship held in Haikou, south China's Hainan Province, Aug. 17, 2019. (Xinhua/Guo Cheng)

Children ride at the Balance Bike Riders' Asian Championship held in Haikou, south China's Hainan Province, Aug. 17, 2019. (Xinhua/Guo Cheng)