'I didn't want to be alive any more': Michael Phelps opens up in brave interview

Sports Illustrated published the lengthy article about Phelps, with not just the swimmer but many of the people closest to him speaking out.

And at the heart of the story is his comeback from his lowest point, in September of last year, when he was caught driving erratically at 1.40am while en route from his house to a casino in Baltimore.

Phelps, whose record of 18 Olympic gold medals is double that of the next-most-decorated Olympian (Soviet gymnast Larisa Latynina), entered a treatment programme and avoided jail, but was suspended from competitive swimming for six months.

"I was in a really dark place,” the 30-year-old Phelps told the magazine. "Not wanting to be alive anymore.”

It is not just Phelps himself who thought he might be in mortal danger: his coach, Bob Bowman, had feared something similar might happen.

"I had been living in fear that I was going to get a call that something had happened,” said Bowman, suspecting that drinking might be the catalyst given Phelps's prior offences.

"Honestly, I thought, the way he was going, he was going to kill himself. Not take his own life, but something like the DUI, but worse.”

One of Phelps's best friends, pharmaceutical sales rep Bob Shea, added that when he finally caught up with his friend after last year's incident things were bleak.

“It was bad,” said Shea. “It was every bit as bad as you would imagine. You could see he was feeling the weight of his actions.

"He knows he has kids who look up to him. He has his foundation. He knew he let people down, and he had no idea exactly what was going to happen.”

Since then, however, Phelps has made a comeback. He is sober, insists that he will not touch a drop of alcohol until at least the end of the Olympics next year, and swimming well having clocked times this year that would have comfortably won him three titles at the world championships, had he taken part.

“Haven’t had a single sip and will not have a sip,” he told the magazine. “My body fat has dropped significantly, and I’m leaner than I’ve ever been.

"The performances were there because I worked, recovered, slept and took care of myself more than I ever had.”

Will he win gold next summer? Still just 30, there is every chance that Phelps will add to his medal haul, according to veteran coach Eddie Reese.

“I think we’re going to see him go faster than he’s ever gone," said Reese. "Faster than [high-tech] suit times. He’s going to be very, very hard to beat.”