The four-day event brings the fittest athletes from all over the world to compete in a range of gruelling exercises.

To qualify, competitors have to place in the top 10 in their age category.

Ms Tynan is ranked fifth in the world in her age category (55-59 years), and this is her second time at the international competition.

"There's a build up to get to the CrossFit Games, you have to compete in the CrossFit Open which is worldwide competition," she said.

"From there, the top 200 in the age group categories compete to qualify for the games. You do five workouts for five days and then the top 10 in the world are invited to the CrossFit Games.

"I qualified fifth [in the world] ... I'm pretty proud."

So how often do you need to train to be a crossfit champion? Well, Ms Tynan completes two workouts a day during the week, one on Saturday with only one rest day - where she swims.

"I am training six days a week with a rest recovery which is a swim day. There are all different kinds of workouts. Sometimes it's [training] for about an hour and half," she said.

She also has a sponsorship with Lotus Health Co which means she counts all her macro nutrients such as carbohydrates, protein and fats.

"Essentially when you're training like this, you have to fuel your body," she said.

Ms Tynan started CrossFit in 2013, and instantly fell in love with the sport.

"I've always loved fitness. I played a lot of sport when I was a kid," she said. "So I decided to give it a go ... I live and breath it now."

Athletes compete in a range of exercises such as gymnastics, obstacle courses, pull-ups, squats or a range of weight lifts - and often against the clock.

Ms Tynan added she is not surprised by the popularity of the sport, and encouraged interested people to have a go.

"It's fantastic. Until you get in and really have a go, you won't see what it really gives people. It doesn't matter how fit or mobile you are, it can better your life," she said.

CrossFit Games will be held on July 29 to August 4 in Madison, Wisconsin.