Why are sports stars prone to depression?
When Michael Yardy flew home from the Cricket World Cup this week suffering from depression, he joined a long list of elite sportsmen who have made the difficult decision to seek help for a mental illness.
England batsman Marcus Trescothick left the Ashes tour to Australia in 2006 with what was described at the time as a "stress-related illness". Later he wrote a book about his battle against depression.
In an interview with BBC Sport programme Inside Sport in 2009, he recalled how he thought about harming himself to prove he had a problem.
"I considered hurting myself just to show people how much pain I was in," he said.
"If you've got a broken leg you've got a cast on your leg, people can see you've got a problem but when you've got mental problems there is nothing evident to people to show you need help."
Boxer Frank Bruno, Celtic football manager Neil Lennon and All Blacks rugby union star John Kirwan have also talked openly about their depression.
Admitting there is a problem is something sports people find extremely hard, not least because they are conditioned to be both physically and mentally tough.
Yet Yardy, the Sussex captain, found the strength to say: "I felt that it was the only sensible option for me and I wanted to be honest about the reason behind that decision."
If one in five people are affected by depression at some point in their lives, then it is not surprising that sports stars are prone to it too.
Ian Maynard, professor of sport psychology at Sheffield Hallam University, says the fact that sportsmen are not naturally emotional does not help.
"They don't wear their heart on their sleeve because that can cause problems in competition, so they tend to be more buttoned-up and get a mentally tough exterior."
Far from family
While some sportsmen are able to separate the day job from everything else and continue to perform at a high level, some cannot, and that is when the problems start.
Cricketers are well-known for the long international tours they have to endure - this latest one has lasted for more than five months and included long stays in Australia, India and Sri Lanka.
The pressures of playing international cricket in an unsettling environment far from family and friends for almost half a year must take its toll.
"If your performance isn't great on or off the pitch, or socially, it makes it even more difficult to hold things together," says clinical sports psychologist Dr Victor Thompson.
He maintains that professional sportsmen are no more prone to depression than anyone else, but he acknowledges that the stresses and strains of performing under constant media scrutiny are great.
When they become depressed it is not just that they are "not coping".
Dr Thompson explains: "To be clinically depressed there have to be symptoms and these have to cause clinical difficulty in the way you lead your life."
"As a sports person it's doing their job, focusing and performing that is affected."
'Washing machine effect'
Following Yardy's admission, former England captain Michael Vaughan was quick to say that depression is not a sign of weakness, but a physical illness.
"There's a lot of pressure playing in a World Cup but if you've got these issues you're never going to get the best out of yourself.
"I bet there are players in other sports who are struggling with depression and aren't being as upfront as some cricketers."
The "washing machine effect", as Professor Maynard calls it, of feeling lonely and isolated away from home with nothing to interrupt the vicious cycle, should be treated with appropriate counselling.
Counselling is the all-important first step. It helps confidence to return and gives a sports star someone to talk to about how they are feeling.
But experts say there are no hard-and-fast rules on how to treat a sportsman with depression.
In Dr Thompson's experience, the counsellor must carefully judge how to gain his patient's trust before trying to offer support.
"Working with a depressed athlete is like working with someone who feels a bit hopeless and negative about everything. You have to be careful and delicate with them."
What works for one sportsman will not work for another. Each depression is different.
During the earlier stages of the England cricket team's tour, the players would have had access to a sports psychologist who was part of their team.
But it is thought he was not present to counsel Yardy, because he too had returned home after months away from his family.
The reaction of friends and family once home is vitally important in starting the recovery process, says Dr Thompson.
"And it doesn't help if commentators are dismissive about it," he adds.