23-time gold medallist Michael Phelps opens up on ‘post-Olympic depression’ 

Five-time Olympian Micheal Phelps has opened up on his mental health struggles in a candid interview with NBC News.

Arguably the greatest athlete to ever compete at the Olympic Games, his 28 swimming medals - 23 of which are gold - speak for themselves.

But even as early as 2004, he began struggling with life after each four-year cycle.

“I would say probably 2004. 2004 was my first taste of post-Olympic depression, you know, coming off such a high,” he told NBC.

“It’s basically… you get to like the edge of a cliff, like ‘Cool now what? Oh, I guess I've got to wait four more years to have the chance to do it again’.

“2008 was my second taste of post-Olympic depression because coming off that high after doing something you set out to do your whole entire life.”

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But from what he once saw as a weakness, the 38-year-old has come to find strength in his vulnerability.

“As a male athlete, I could tell something was off. But I think I saw it as a sign of weakness and if I shared anything about it then it would give my competitors an edge,” he continued.

“I’m trying to be better than anybody has ever been. So for me, I looked at it as a weakness.

“I had to learn vulnerability is a good thing and it was scary at first, but I learned that vulnerability just means change. And for me, it was a great change.”

Over the weekend, Phelps paid respect to ‘influential’ swimming coach Jon Urbanchek following his passing on 9 May.

“I’m beyond grateful for the time I got to spend with [Urbanchek],” he wrote on Instagram.

“Thinking about what he taught me in and out of the pool… one of the most influential people I’ve had in my life.

“This man is a legend and truly one of one.”