Olympian Olivia Sandery has overcome an early penalty to set an Australian record in winning the 35km national race walking championship.

Sandery crossed the line in 2:45:31 at Melbourne's Albert Park on Sunday despite suffering a 3.5 minute penalty before the halfway mark.

Her time was more than two minutes better than the previous best of 2:47.34 set by Rebecca Henderson.

In the men's event, Rhydian Cowley took his third 35km title from as many starts, finishing in 2:32.33, with both winners posting qualifying times for the 2025 world athletic championships in Tokyo.

Leading early alongside runner-up Elizabeth McMillen, Sandery came out firing after serving her penalty for a third card.

"As soon as I left the box, my one goal was to catch up to Lizzie [McMillen]. Once I got there, I was feeling good and thought why not go for it," she said.

"That's what I'm proudest of, not getting too in my own head about it. It would have been easy to pull out or give up, but I knew how fit I was and really didn't want to waste the opportunity."

McMillen clocked 2:47:26 to sneak under the 2:48:00 world championships standard, while Allanah Pitcher finished third in 2:57:51.

In the early stages of the men's event, Cowley kept pace alongside rising stars Will Thompson and Mitchell Baker before striding away to finish more than a minute clear of his nearest rival.

Thompson finished second in 2:34:15 with Baker posting 2:35:06.

"It was great to walk together with Thommo and Mitch most of the way and drag them through to some good times," Cowley said.

"It has been hard work getting back into training after the Olympics but I know those young fellas are coming for me, so I had to put in a bit of work to keep them off."