"At the moment I'm doing a bit of everything, right down to the cleaning. When you have the passion for something you tend to go the extra mile."
The gym has about 400 members on the books.
People of all shapes and sizes were welcome at Club Fitness, with a focus simply on results.
"That could be people who want to transform into a different body, lose weight, increase muscle or just be happier," Munson said.
"Exercise obviously has an important role to play in mental health improvement as well.
"One key difference here is that we don't have the judgemental stigma that is associated with other gyms."
Munson's own fitness journey began in 2006, when he studied to become a personal trainer at the New Zealand Institute of Sport in Wellington.
After his first stint at Club Fitness, he moved to Jetts in Palmerston North and brought that franchise to Whanganui.
"Jetts Whanganui reached about 700 members and then I took off to London to do the same sort of thing at Anytime Fitness in Clapham South for five or so years.
"Then, it started to feel like it was time to come home. I'm loving being back."
Outside of personal training, he enjoyed a lengthy stint as the KPW (Kiwi Pro Wrestling) champion as H-Flame, holding the belt from 2006 to the end of 2009 and the KPW tag team championship with Lazarus Volt from 2011 to 2013.
While in the KPW stable he rubbed shoulders with another Whanganui wrestler, Chris Delorean, and trialled for the WWE in 2008.
Bringing back regular assessments and workout routines were on the top of his to-do list at Club Fitness.
"Getting some more modern equipment is another one. We want to show that we're putting money back into the business.
"There is definitely a club feel here. Everyone knows your name and eventually we'll have open days and barbecues."
