Kumiai Ryu High Impact Martial Arts' Muay Thai competitors Jesse Astil and Dallas George hit the gym over the Christmas break with an eye on competition at nationals on Australia Day.

And it paid off.

The duo both claimed gold medals and with them tickets to the IFMA Muay Thai World Championships, with Astill heading to Morocco and George to Thailand.

The gym's Renshi Anthony Wharton it was a "big deal" for the duo to come out on top.

"They worked hard through the Christmas break to continue to be in perfect shape for the nationals," he said.

"It establishes the year for them. Muay Thai have their nationals early as Australia selects its team for worlds from it, and you have to win your division in nationals in order to get picked."

Both took part in a knockout competition, and both competed a division up from the one they entered, with divisions decided based on experience and weight.

Astill's finals match was against an opponent with 15 fights who Wharton said was "far more experienced" than the 19-year-old, but won with a knockout to claim the title.

George, who competed at the international level in 2019, was also bumped up into a less crowded but tougher field with just the one opponent, with the 12-year-old claiming a "pretty comfortable" points victory.

"We're very, very proud," Whartson said.