HT Tran fell into personal training by accident.
"I actually came to this gym here, [the KGV Recreation Centre in Sydney] just to be a member and they were short of staff and asked me to apply."
That was in 2000. In 2008, when the GFC hit, he decided it was time to specialise, so he could stand out in an increasingly competitive market.
Golf performance - and the use of technology - would be his new niche.
"I'll use 3D to capture [a client's] swing, so we take out the guess work, find out how fast they're moving, any ratios of speed. Then from there we write some programs to help them with their needs."
To get started, HT invested $20,000 dollars in hardware and software.
"But I found that the return came back a lot quicker because you're giving yourself an extra edge, using technology to teach. So you can charge a little bit more."
Now, 60 per cent of his clients are golfers, including pro golfer Chris Akers, who HT sponsors. His Healthy Drive logo appears on Chris' shirts and caps - a marketing move that's opening up new business opportunities.
"Now I have people who are not my clients who want to buy some of my clothing or the caps. And now I'm moving into selling some [golf] nets... working with US owners, so I'll be distributing in Australia."
HT says the next step is for the business to grow to a point where he can hire another trainer. He's currently establishing systems to make his teaching more efficient and easy to replicate.
But when he considers the sacrifices his family made when coming to Australia, he says he sometimes worries he's not working hard enough.
"We were refugees, we escaped from Vietnam. Dad sold out his coffee business, took five brothers, mum and a couple of sisters and came over here," he explains. They arrived in Australia in 1979.
"It's only when you ask your clients, you see it from a different perspective. So you've got to learn to don't be too hard on yourself when you're working on your business."