Now they are representing Australia in the sport they have grown to love.

The pair are off to Edmonton in Canada to compete in the International Triathlon Union (ITU) World Championship in September.

"We always wanted to do a sport together," Raea said.

"We thought [rather than competing in a team sport] let's do our own thing - we can head out the back door and go for a run, or go for a ride," Holly said.

They spend two to three hours a day training during the week.

Sometimes, at weekends, they train for up to four hours.

"We can't always train at the same ability. We'll wake up at the same time, both head out the door at the same time and train as much as we can together," Holly said.

"We've got the same goal, and we drive and motivate each other," Raea said.

An early taste of success encouraged the pair to continue to push themselves.

But they are still in disbelief that their "hobby" has taken them so far.

Holly and Raea qualified for the President's (elite) team for the Olympic-distance triathlon, which consists of a 1.5 kilometre swim, 40 kilometre cycle, and a 10 kilometre run.

Holly also qualified for the Ironman 70.3, or the half-ironman, which is a 1.9 kilometre swim, 90 kilometre cycle and 21 kilometre run.

Although she qualified for both events, Holly decided to compete in just the half-ironman.

"I could have done both, but I decided to pick my pet event and I think I'll be really competitive in it," she said.

The pair will fly to Canada shortly for more training before their races begin. Raea's event is on Monday, September 1, while Holly's is on Sunday, September 7.

"As soon as I finish I get to eat whatever I want while Holly will have to stick to her diet. I'll just be holidaying," Raea laughed.

Qualifying for the championship has strengthened the pair's resolve to see just how far they can go.

"You see your results, and you think 'Wow, what else am I capable of'?" Holly said.