The 16-year-old Emmanuel College student took out the top prize in her division at the 2009 Australian Karate Federation Championships on the weekend.

Sonia out-fought six other girls throughout three rounds in the 53-59kg junior female kumite division for first place, including several of her Team Victoria teammates.

The championships, which were held from August 7-9 in Adelaide, attracted young competitors from around Australia.

Each squad hosted around 40 fighters with the exception of the large Victorian side, which took more than 100 competitors to the championships.

"It was very hard to fight (teammates)," she said.

"We know each other and know how each other fight.

"You can use it as an advantage or a disadvantage."

Sonia has been part of Team Victoria since the start of the year and travels to Melbourne via the train once a week to practise with the side.

She also trains two nights in Warrnambool and teaches a class at Nirranda every week.

Having been involved in the sport for close to eight years, Sonia has only just begun to explore the competitive side of karate.

"I've never thought of it as more than a fun sport until this year," she said.

"It's a lot of hard work, but it pays off."

Sonia took out second-place in the Victorian Open for her division and won gold at the Australian Open which hosted competitors from as far away as Germany.

Sonia will now enjoy a six-month break from competition but plans to keep practising the sport in the future.