More than 5000 runners and walkers have laced up to take on the course in a festival-like atmosphere, thanks to new on-course entertainment Run Out Loud.

Seven-time Ironman champion and former Olympic long-distance swimmer Ky Hurst blitzed the 10-kilometre course wearing a Westpac Lifesaver Rescue helicopter suit.

A little bulkier than his usual running attire, the Canberra Times Fun Run ambassador said he wasn't the only one sweating.

"It's not the easiest thing to run in, the real chopper cuts through the air a little easier than I did," he said.

"It was just awesome the local support showed here in Canberra, for the community to step out and have a wonderful morning is just fantastic."

Rowan Walker won the 14km Fun Run. Kelly-Ann Varey was the first woman over the line.

Nathan Arkley finished first in the wheelchair elite fun run, followed by Jake Lappin and Richard Colman.

Flanked by four generations of his family, 80-year old Leslie Ion crossed the finish line in his goal of 10 kilometres in under 80 minutes.

He ran alongside his grandchildren and great-children wearing "Grumpy Old Man T-shirts".

He said it meant "everything" to have them there.

"Sometimes you need a shirt to show your support," his granddaughter Heidi Yates said.

Out celebrating Father's Day was Dan Kite of Higgins, racing with his two-year-old son Gus in the pram.

He said he was trying to instil good habits in his son early.

"If he sees me running all of the time, hopefully when he's big enough he'll do it himself," he said.

Greg Leach of Lyneham was also spending a bit of father-son time with his son Harry, aged three.

In previous years, his six-year-old daughter has also been out on the course with him, but she's getting too heavy to push in the bicycle pram.

"I'm hoping she'll run alongside me next year," he said.

Fun run organiser and head of sport at Fairfax Events Chris Secker said he wanted people to leave the headphones at home by enjoying stations of music across the course.

"The best part of a run is enjoying the atmosphere around you," Mr Secker said.

"We've actually brought in DJ Hot Dub Time Machine and he's inviting people to run through the ages with him.

"There are different music stations across the course celebrating different decades of music and we've also got a number of local bands participating. It's a feast for the ears."

So far this year, the fun run has raised more than $70,000 for many different charities.

And with Father's Day today, Mr Secker said there's double the reason to celebrate.

"This is the 40th year for The Canberra Times Fun Run and it's got a lot of history to it so there are people taking part who've run it for a long time," Mr Secker said.

"Then there are also some people who are trying it for the first time as well. There are some nice stories of fathers and sons doing it together and dads and daughters and full families are doing it together as well."