Todd Hays' brain injury could heal within three months and without surgery, an outstanding prognosis for the U.S. Olympic bobsled veteran who dropped his bid to make the Vancouver Games and retired after learning the extent of damage sustained in a training crash last week.

Hays will need further evaluation of the bleeding in his brain and will be monitored for weeks, but has full neurological function.

"I think about how lucky I've been that I've made it this far and enjoy my health and have so much fun and success doing it," Hays, a former college football player and kickboxer, told The Associated Press. "That's why this decision for me is easy. I made it this long. I've enjoyed a great, great career. I've had an incredible amount of fun and an 16-year incredible adventure in the sport of bobsled."

Hays, a three-time Olympian and 2002 silver medalist from Del Rio, Texas, retired Monday after being told his injury was worse than the preliminary concussion diagnosis. He crashed in a World Cup training run last Wednesday in Germany, and both sledmates and other U.S. teammates immediately knew Hays was seriously hurt.

"I've seen a lot of bobsled crashes and a lot of guys walk away pretty loopy, but I've never seen anybody look the way Todd did when they walked him to the ambulance," said Steven Holcomb, the reigning four-man bobsled world champion and pilot of USA-1.

U.S. bobsled officials flew Hays back to the team base in Lake Placid, N.Y. over the weekend for evaluation. When a CT scan and MRI showed irregularities, Hays _ who expected to be sidelined no more than a week _ was told more trauma could cause irreversible brain damage. Presented with that information, the 40-year-old made the choice to end his career.

"Right now, resting and letting the brain heal itself should take care of the problem," said Dr. Eugene Byrne, the USBSF's chief medical officer.

Concussions are not uncommon in sliding sports, where racers routinely speed down ice-coated concrete tracks at 75 mph or more, with little more than a helmet for protection. But in Byrne's six years with the U.S. Bobsled and Skeleton Federation, Hays' CT scan was the first to show any abnormality.

"There's a lot of risk within our sports," U.S. skeleton racer Eric Bernotas said. "I'm just glad it sounds like he's going to be OK."

When Hays drove to an Olympic silver at Salt Lake City in 2002, it ended a 46-year medal drought for U.S. men's bobsledding.