He has barely touched a basketball in three years but former Wollongong Hawks captain Mat Campbell looks like the same trim and taut bloke who played 17 years in the National Basketball League.

"I'm definitely not at my playing weight," Campbell insisted.

"I've tried to stay as trim as possible. I do crossfit once a week and surf as much as I can, but I do a lot more paddling than most people out there, more paddling than surfing."

Campbell will leave his surfboard at home on Sunday when he lines up in the annual Splash 'n' Dash Festival at Wollongong Harbour.

The 38-year-old father of two said the event, which is run with the support of the Leukaemia Foundation, was raising money for leukaemia research.

Campbell has gladly accepted the role of 'Kids Ambassador' on Sunday and will run the 2.5km course with wife Renee and their daughters Hannah (7) and Sarah (4).

"The thing about leukaemia that a lot of people don't realise is that it doesn't discriminate. It just picks anybody randomly," he said.

"I'm happy to put my weight behind it and hopefully give a great cause that little bit more exposure.

"I'll say a couple of words before the race and run with the kids.

I've registered the whole family so we'll all be in it and I'll be handing things out at the end."

The two-day Splash 'n' Dash Festival gets under way with Saturday's swimming events, with Sunday centred around the various fun runs.

Campbell does his best to stay fit.

"I go for a run here and there but the legs have had that many years of hard court surfaces so I try to give them a rest," he said.

"I enjoy doing the king of the kids thing, get on the bike track with my girls.

"We're lucky in Wollongong that we've got one of the best bike tracks in the world, from Wollongong all the way to Thirroul. I get out as much as I can with the kids."

Event organiser Rob Battocchio hopes to see "several hundred competitors".

"It's great to be working with the local branch of the Leukaemia Foundation and we are promoting their message of getting your blood pumping to prevent cancer," Battocchio said.

"It's not about winning ... it's about getting out, having a go while raising funds to help those who need it."