The governing body of swimming says there is "no factual basis" to doping speculation surrounding Chinese teen gold medalist Ye Shiwen.

The 16-year-old Ye broke the world record in the 400-meter individual medley and won gold on Tuesday in the 200 IM. The head of an American coaching organization questioned her legitimacy.

Ye was peppered with more questions about performance-enhancing drugs after her victory in the 200 IM. She denies she has used banned substances and says her success is because of hard work.

The governing body, FINA, says Ye has been tested four times in the past year, including twice before her country's Olympic trials this year.