Jason Patchell, senior sports psychologist at the Australian Institute of Sport, has never met Thorpe but he said such personal struggles could have serious effects on performance for an elite athlete.

“Any significant inner turmoil over any personal issue - whether it’s sexuality or anything else - certainly has the potential to cause anxiety, worry and also a sense of isolation,” Patchell said.

“Depression and anxiety disorders can have quite a significant impact on an individual’s functioning, in terms of their motivation, energy level, their sleep, their eating patterns ... so when you put all that into an athlete’s plan to achieve their goals, it certainly makes it more challenging day in, day out.

“So look, it is quite surprising, it is also quite impressive that he’s been able to manage those feelings at the same time [as he was swimming at the elite level].

“Certainly athletes have a significant level of resilience. That doesn’t mean they’re immune to what all human beings face and that is mental illness and those struggles that life can present.''

Thorpe revealed his battles with depression and suicidal thoughts in his 2012 autobiography This Is Me, something he said he used alcohol to deal with, but in it he still denied years of speculation he was gay.

He came out in an interview with Michael Parkinson, broadcast on Channel 10 on Sunday night, describing the concealment of his sexuality as “such a weight”.

While not singling out the denial of his sexuality as the cause of his depression, he said it “didn’t help”, and encouraged others in a similar situation to come out, saying “it feels better to lift this and get this out”.

Patchell said Thorpe’s revelation would provide reassurance to other athletes struggling with their sexuality.

“I think it is a very brave thing to do,” he said. “It would certainly provide a lot of reassurance to other athletes in similar situations, reassurance they have a right to be proud of who they are and that they’re also not alone in that situation,” he said.

For athletes in a similar situation, Patchell's advice was to use the support available when they are ready.

“[Coming out] is a very private decision that only that person can make,'' he said.

“It’s important to acknowledge that for some athletes, this type of situation can be quite challenging and stressful, but also at the same time that there’s support available.”

Brumbies player Clyde Rathbone, who wrote about his "bromance" with an unnamed gay sportsman, applauded Thorpe's revelation.

"I think it's great that he's come out and spoken openly about it; I think he can be a great role model for people because of his profile," Rathbone said.

"Hopefully we can get to the point where it's not required to be a big media event and people can just be who they are."

With David Polkinghorne