Blistered and scarred, American sprinter Justin Gatlin arrived at the world championships with frostbite on both feet.

The 2004 Olympic champion, who last year made his return to competition after serving a four-year doping ban, said Wednesday he got frostbite about two weeks ago after going into a cryogenic chamber with wet socks.

He didn’t lose any toes and will still run in Daegu, but his wounds are not completely healed.

“You wake up at 9 o’clock in the morning in Orlando and it’s already 90 degrees (32 C),” said the 29-year-old Gatlin, who lives and trains in Florida. “So we’re already hot, drenched with sweat. Get in the booth, socks were wet, socks froze to me instantly.

“Before I even came here it was like walking on fiery pins and needles,” Gatlin added in an interview with The Associated Press.

Athletes use cryogenic chambers to cool their muscles after a hard workout. Instead of ice packs, the chamber works faster and covers the entire body.

But instead of being worried about his ailment ahead of a possible showdown with world-record holder Usain Bolt in the 100

meters, Gatlin is using the setback as inspiration.

“Honestly, it’s just the universe telling me, ‘How much do you really want this?’“ Gatlin said. “‘If you really want this then I’m going to put these obstacles in your way and see how man enough you’re going to be to overcome them.’“

Gatlin said the pain from the frostbite has subsided and the injury hasn’t affected his stride. But it is still bothersome because the wounds on his heels are near the level where his socks sit and where the back of his running spikes touch.

“It’s better than it was. It was all pussed up and blistered. It bubbled up and it stayed bubbled up for a good four or five days,” Gatlin said, lifting up his sweat pants to reveal the scabby scars that resemble big blisters. “This is the best it’s looked, the best it’s felt.

“The confidence in me is rising. I’m getting ready to get out there and burn the track.”