Casey Stoner's doctor, Claudio Macchiagodena says the Australian has the fatigue of a man twice his age, after spending last week examining his condition.
Stoner has been ruled out of the next three MotoGP races to give himself time to recover from the health problems that have blighted him throughout the last two months.
Dr Macchiagodena says Stoner needs time to rest but believes he could be fit again before the end of the season
"I've been around Casey for a week. He's only 22 but he has already accumulated the fatigue of a 50-year-old person," he told Gazzetta dello Sport.
"His crisis isn't acute but it has already brought up symptoms with his stomach, his anemia and various pains that must be investigated thoroughly and not with the occasional medical tests done so far.
"With a one-month rest he'll be back in shape, while with two months he'll make sure his body is fine. He won the 2007 title, so if he manages himself without mistakes he'll be great again."