Two remissions, one relapse and three years later, Ms Sewell and nine women she regularly drives into the ground at her gym have a bold new scheme.

They plan to walk 250 kilometres to raise money for breast care nurses.

The group will set out on the Great North Walk from Sydney's Macquarie Place in October, and finish at Newcastle Harbour.

They hope to raise $20,000 for the McGrath Foundation.

"Nicki got out of hospital, and just a week later she wanted to do extreme sports," group member Lydia Balnave said.

"She's an inspiration. Now the rest of us can't whinge."

Ms Sewell said the group takes on a different challenge every year, including triathlons, half-marathons and long distance swims.

She says she wants to help breast care nurses because of the support they've given her since the first diagnosis in January, 2007.

"[The McGrath Foundation] is very dear to my heart," Ms Sewell said.

"The nurses played a huge role in my recovery, and they're really positive and make you feel really special."

The group, aged from 30 to 45, will have to reel off up to 35 kilometres a day if they are to reach Newcastle by October 9.

Their path snakes through Ku-ring-gai Chase National Park, Brooklyn, along the Hawkesbury River, and through the Watagan State Forest before reaching Newcastle's southern edge.

Ms Sewell is looking for businesses to sponsor the trek, and will host a trivia night fundraiser on Friday, May 21, at Morisset Country Club. About $4000 had been raised at the time the Lakes Mail went to press.

Visit everydayhero.com.au/greatnorthwal k2010.