His clients include some of the hottest acts in Canadian music. Sean Maingot, however, had to overcome cancer to keep them looking as fit as they sound.

Eight years ago, Maingot was a healthy 22-year-old whose life was about to be turned upside-down.

“I had a really deep nasty cough that I hadn’t had before and I didn’t know exactly what it was,” Maingot told CTV News. “I found out it was a tumour.”

Doctors diagnosed Maingot with a rare and aggressive form of cancer called lymphoblastic lymphoma.

“They told me it was about the size of a softball and it was right in the centre of my chest and that is how they described it.”

Maingot was forced to undergo a punishing regime of chemotherapy that left him thin, weak and demoralized. But the treatment worked, and slowly Maingot regained his strength and became determined to make his feeble body fit again.

“If you feel sorry for yourself, eventually people will stop feeling sorry for you,” he says. “So you have to take yourself from that spot to a different spot.”

That philosophy has taken him sickness to fitness. Today, Maingot is the co-founder of Body by Chosen: a Toronto gym that is helping others find their inner -- and outer -- strength.

Maingot’s clients include Grammy-winning Canadian superstar The Weeknd and hip-hop producer Matthew Samuels, a.k.a. Boi-1da, who has produced tracks for artists like Drake and Rhianna.

“It just goes to show that anything you put your mind to, you can do it,” Samuels told CTV News. “You can’t be defeated by anything –- only yourself can be defeated by yourself.”

It’s that inner strength that Maingot channels to get his clients into shape.

“I think, going through what I did, I think it helped me be able to help other people more,” he said.

With a report from CTV News' medical specialist Avis Favaro and producer Elizabeth St. Philip