The Formula One champion Michael Schumacher is reported to have lost a quarter of his body weight since doctors placed him in an artificially induced coma to help him recover from brain injuries sustained in a skiing accident last December.
Schumacher's weight had dropped from 75 kg to just 55 kg in the 83 days since he was placed in a coma, according to reports in German media.
"Weight loss in coma patients is normal," Professor Dr Kurt Diehm, a coma expert at Germany's Karlsbad teaching hospital told Bild. "One must assume that his muscles have degraded considerably because of his immobility."
Schumacher, 45, suffered a serious head injury after striking a rock during a skiing accident in the French resort of Meribel. He is being treated at a hospital in Grenoble, where his family, including his wife Corinna, is maintaining a bedside vigil.
Officially, the injured driver is now in a "wake-up" phase as doctors gradually reduce his drug intake in an attempt to bring him out of his coma. Yet signs of a recovery have been minimal. "His family is incredibly strong, they won't let themselves be discouraged," the driver's manager Sabine Kehm said earlier this week.
She stressed that Schumacher had not yet woken up, adding: "We are still waiting for this to happen but we have learned to accept that it can take a long time".
Doctors are reported to have told Schumacher's family that the driver's chances of recovery are minimal. Last month, Germany's Focus magazine reported that complications had obliged doctors to halt his wake-up process and that the driver had been put back into a coma.
Schumacher's management team denied that report.