Selwood, a former St Therese's Primary School student, went back to his old stomping crowd to help encourage some of his biggest fans to take part in next year's event. 

The AFL star was king of the kids on Monday, signing autographs, posing for photos and running a training session with eager students. 

"It feels really good to be back," Selwood told the Bendigo Advertiser. 

"It (the school) has changed a lot but I have some great memories here."

Selwood said the Bendigo TRYathlon was a great chance for kids to get active. 

"Anything that gets the kids up off the couch and exercising is good," he said. 

"There is obviously three legs to the triathlon and if some of the kids end up liking one of the three then that will be a bonus for parents in particular.

"Obesity is a huge problem with young kids these days, so if we can limit the damage that is happening, then that will go a long way to fixing the problem."

The TRYathlon is designed for kids aged between seven and 15-years-old, no matter what their abilities are, with every participant receiving a gold medal. 

Weet-Bix Kids TRYathlon representative David Meade expected about 1000 local kids to take part. 

"The main transition area for the TRYathlon will be at the QEO, the ride is around Tom Flood and the swim in Barnard Street," he said. 

"It is widely regarded as the best venue in Australia."

Meade said the TRYathlon wasn't about who came first but about having a go. 

"They don’t need to be elite athletes, you don't need to have any high level of fitness, it is just kids having a crack," he said. 

"It is about getting out there and having some fun and completing the course." 

The Bendigo TRYathlon will be held on March 1, 2015. 

For more information and to register for the Bendigo event visit try.weetbix.com.au