The 19-year-old - at one point sporting a sparkling green cape - was not out of place among the largely young crowds, walking at a gentle pace as he continues his recovery from a recent ligament injury.

"It's taped and I'm doing everything right," he said.

"I'll be back on the court trying it on Monday."

The world number 37 and two-time Grand Slam quarter finalist joined brother Christos and others from the Gold's Gym team in Fyshwick as part of efforts to raise money for cancer awareness.

Most of the nearly 3500 participants had smiles on their faces as they walked or ran laps under perfect blue skies, but many had stories of heartache which had inspired them to take part.

Lucy Badzim, 37, from Narrabundah, lost her older sister Nives Leslie to a brain tumour in 2012 and nominated her as one of three relay heroes for the Canberra event.

Ms Badzim recalled the anguish and test of faith of seeing her energetic sister lose her life six months after giving birth to twins, Cara and Jacob.

"She was my hero - her infectious laugh and love of life continue to inspire me to be a better person," she said.

"You never think it will happen to you, and then it does, and you realise you are not alone."

Ms Leslie's husband, Brian Leslie, walked with the twins on Saturday.

Cancer Council ACT fundraising events manager Lisa Meares said 211 teams had registered for the 16th annual event.

She it was a nice touch to have Canberran Kyrgios on board for the first time.

"We've got a lack of celebrities here in Canberra, so it's great to have a local sportstar here," Ms Meares said.

Ms Meares said the Canberra event had raised $485,000 by 5pm on Saturday, with an ambitious target of $700,000 set to support the council's important and relevant work.

"We run prevention education services, a wig service for those undergoing treatment, and the 24-hour Cancer Council helpline," she said.

"There's only one degree of separation between most people and cancer."