Instead, she joined about 5649 dedicated participants who draped themselves in capes, wearing crazy hats, wigs and tutus to walk or run along Lake Burley Griffin for the capital's edition of the Mother's Day Classic.

Ms Robb - a self-confessed fun run and half-marathon devotee – was accompanied by her children, Scarlet, 7, and William, 4, in tackling the 5km course.

"It's for a good cause and a fantastic event for people to gather together," Ms Robb said.

"It's good to get out there and do something. We'll be back next year."

Canberra organising committee member Bina Brown said the turn out had been down on last year, but blamed the dreary autumn weather.

"Wild winds didn't seem to take away from the atmosphere which, as always, was fun mixed with emotion as people dressed in every imaginable whacky pink outfit ran or walked for someone suffering, or who has lost their lives, from breast cancer," Ms Brown said.

"The organisers are extremely thankful to those that did brave the cool conditions and helped to boost the overall fundraising efforts."

Ms Brown said Canberra Girls Grammar School won the prize for largest school team, while Team Amy Hickman took out the family and friends team category at the same time, raising $9000.

Other category winners included Lockheed Martin (largest corporate team), Marcus Clarke Mayhem Team Education and Training (largest government team), and Medical Women's Society of the ACT (largest community group).

Nationally, organisers estimated about 135,000 participants across 104 events, across capitals, major metropolitan areas, and 93 regional towns.

Organisers believe money raised from the event will surpass $3 million – which would mean more than $27 million had been raised since the event's inception in 1998.

The event is the single biggest donor to the National Breast Cancer Foundation, which has used money raised in research project such as the investigation of new DNA patterns in breast cancer cells, and the rehabilitation of women after breast cancer surgery.

This year's event is expected to help fund a number of new projects, including using nanoparticles for targeted treatment of aggressive breast cancer, breast cancer prevention, and a study to better understand the long-term side effects of treatment in survivors.

National chair Louise Davidson said the event also aims to honour and support those affected by breast cancer.

"For every pink wig and tutu out on the course, there were participants wearing tribute cards to honour loved ones living with breast cancer or to remember those lost to the disease," Ms Davidson said.

"We try to make Mother's Day Classic a fun and memorable day out, but we never lose sight of our purpose."

Donations can still be made at mothersdayclassic.com.au/donate.