Report by ITV Granada Reports correspondent Andy Bonner.
A rugby player whose mental health deteriorated after a serious injury ruined his career is helping young people "banish their daily demons" through exercise.
Jamie Acton, 29, played rugby league for Leigh and Oldham, but his time on the field was cut short after a significant neck injury.
In January, he was banned for two years after a stored sample of his urine was retested and found to contain a performance enhancing drug.
The retired rugby player has battled with his mental health and drug taking throughout his life, and the end of his career was almost the final straw.
"That led me into a deep, deep depression to the point where I don't want to be here anymore", Jamie told ITV Granada Reports.
"And the only shining light in my life other than my family and support network was exercise. It was the only time I felt happy.
"What I started to realise was actually a lot of other people would be able to benefit from exercise the same way that I do."
Jamie said he accepted the drug charges brought against him in January, and wants to use his battles with drugs for good and ensure others do not follow the same path.
He is now putting teenagers through their paces, at Wigan Youth Zone, to prove that working out can be good for the mind as well as the muscles.
For Caitlin, the classes with Jamie have come after a particularly difficult time.
"I've been quite a quiet person", Caitlin said. "Lockdown didn't help at all. Isolating, it was quite lonely.
"I'm now very confident. I talk all the time. I'll do whatever is thrown at me."
Jamie has created an app called Banish, which uses exercise to rid people of their psychological demons.
He hopes it will keep youngsters both physically and mentally healthy long after his sessions have finished.
Hannah Jenkins, from Wigan Youth Zone, said: "The past 18 months have been really, really hard on our young people.
"We've seen an increase in loneliness and we've seen an increase in the social skills declining.
"Something like this is really benefiting that in a way that's also improving other aspects of their health as well."