Instantly, he was told to take it easy and not to push so hard.
Old habits are simply hard to break.
It's not in the nature of Gay, one of the fastest men on the planet, to do anything slow, especially when his hip is feeling better than ever just three months after surgery.
A quick healer, Gay is already turning his attention toward the London Olympics and trying to close the gap on record holder Usain Bolt - a predicament he shares with every other sprinter in the world.
Gay's goal is to begin training at full speed by December and possibly start competing in February. He still plans to run both the 100 and 200 metres at the US Olympic Trials in June, hoping to set up a showdown in London with Bolt, the Jamaican sensation.
closer to full strength
And this time, Gay vows to be closer to full strength. Between a hurting hamstring and an aching hip, Gay estimates he's been sprinting at about only 85 per cent over the past few seasons.
"Fixing this issue is going to make me a better athlete," Gay told The Associated Press in a phone interview Tuesday.
Still, he realises he's a long way from being at Bolt's level again - if he can even get back there at all.
That sceptics doubt him has provided motivation. He knows there are those writing him off, believing that a 29-year-old Gay coming off hip surgery is no match for Bolt.
And that Bolt's countryman, Yohan Blake, is a bigger threat to Bolt than Gay.
"I love it," Gay said of being the underdog. "It's going to keep me working hard. Look at last year: I was running basically on one leg and still running extremely fast times. I think once I'm 100 per cent healthy, I shouldn't have any issues."
Gay could've limped through last summer, picked a select few races to test the hip and endured the searing pain after the competition. But with London quickly approaching, the former world champion elected to shut it down.
A former star at the University of Arkansas, Gay pulled out of the 100 at US nationals in June because of the ailing hip. Soon after, he underwent surgery.
At the World Championships in Daegu, South Korea, in August, Gay was hobbling around the venue while Bolt was flying around the track.
Although reduced to watching Bolt from the sideline, Gay didn't witness his top rival win the 100 in South Korea.
No, Bolt was knocked out of the final after he jumped the gun and was disqualified under a highly debated zero-tolerance false-start rule enacted last year.
It's a rule that Gay doesn't fully support.
"We work too hard for four years," said Gay. "A lot of things can happen in that type of environment, so I believe someone needs a second chance."
Bolt later atoned for the mistake by winning the 200 - in convincing fashion. He's clearly the face of track, and clearly deserves to be, in Gay's opinion.
"What he's done is a little bit more phenomenal than what people have done in the past," Gay said. "That's what separates him from everyone else."