Tyson Gay may be running 'too fast for his body' in chasing Usain Bolt

• American says nutritionist is trying to find problem
• Latest injury causes New York withdrawal

Tyson Gay has been told by a specialist that he may be "running too fast for his body" after his latest injury setback. The second fastest man in history has withdrawn from tomorrow's New York Diamond League meet because of a hamstring problem.

Gay sustained his latest injury in running a world-record 19.41sec on a straight 200 metres track in Manchester last month. He says he can break Usain Bolt's 100m mark by going under 9.5sec, despite troublesome advice from a nutritional specialist whom he is due to see this week.

"He thinks I'm running too fast for my body," Gay said. "It's one of those things that there is no reason, at 27 years old, that I should be getting injured every year – my groin, my knees, my hamstring, my back. It's something I could be deficient in and he wants to find out the problem, why my muscles can't handle me running that fast, why my body is not letting it happen.