The increased threat of athletes suffering from addiction, depression and eating disorders has led to Covid bubbles in sport being branded "completely unsustainable" by a leading mental health charity.
Sporting Minds said it had already treated more than 900 athletes struggling with their mental health over the past two years.
It also warned that another 18 months spent going in and out of sporting bubbles would cause "a huge spike" in those who need their help.
It comes as England 's cricketers prepare to head into another bubble as they travel to Australia to take part in the Ashes series this winter.
Quarantine periods mean players will be forced to spend even more time away from their families, having been in and out of biosecure groups for more than a year.
As a result, many have been left torn between accepting the honour of representing their country in a huge Ashes series and protecting their own wellbeing and that of their family.
All-rounder Ben Stokes is one of the many high-profile athletes who have already chosen to take a break from their sports to protect themselves, alongside the likes of Olympic gymnast Simone Biles and tennis star Naomi Osaka.
A Daily Mail investigation uncovered the scale of the problem across sport, with experts saying the psychological damage caused by being stuck in bubbles could last forever.
Callum Lea, founder of Sporting Minds, spoke of a massive increase in the number of athletes being referred to his charity during the pandemic.
"It's been brilliant that athletes have had the strength and courage to take themselves away from that environment," he said.
"You have to deal with your mental wellbeing first because if you don't, you're not going to have a long and sustainable career.
"[The situation is] completely unsustainable. If bubbles go on for the next 18 months, then Sporting Minds is going to see a huge spike in referrals."
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Mind coach Don Macpherson added: "There's never been a situation like this that is so threatening to players' mental wellbeing. It is out of control and threatens to be more out of control.
"When you have too much time on your hands, you are a sitting target for anxiety and depression.
"Bubbles cause higher levels of intensity, intensity produces anxiety, anxiety can produce depression, that's the slippery path. Sadly, I've seen a huge increase in depression in young sports people, especially aged between 16 to 24.
"I've spoken to England rugby players, England football players, tennis players at Wimbledon, snooker players. They feel restless, trapped, claustrophobic, flat emotionally.
"They are anxious and don't know why, and have no idea what to do or where to go."
