The Mount Maunganui Weet-Bix TRYathlon is sold out this weekend, with a record 1400 children, aged seven-to-15, entered in the annual event.

Held at Arataki Park, the age-appropriate course includes a 50-150m swim at Baywave, a 4-8km cycle around the streets surrounding the park and a 1.5km run.

All participants receive a medal on the finish line and ambassadors handing out medals this year include Tauranga Olympic canoe slalom silver medallist Luuka Jones and retired New Zealand heptathlete and high jump champion Sarah Cowley-Ross.

Welcome Bay twins Sam and Levi Mitchell, 9, will be doing their third Weet-Bix TRYathlon this year and their second at Mount Maunganui.

'It's really fun,” says Sam. 'The bike is my favourite, and you get a really cool t-shirt and a medal at the end. When I finished the TRYathlon in South Auckland I got a high five from (world shot put champion) Valerie Adams.”

Levi says he is always 'really tired” at the end, but there is extra motivation to get to the finish line.

'I like the prizes they give away at the end, even though I haven't won one yet!"

The Mount Maunganui TRYathlon is the first of the 2017/2018 season that will see 17 events completed throughout the country between December 2017 and April 2018.

The Weet-Bix TRYathlon series has been running since 1992 and more than 300,000 Kiwi kids have taken home a medal during that time.

The event is all about giving it a ‘TRY' and participants also get a certificate, an official t-shirt, a drawstring bag and a swim cap as well as complimentary breakfast and a chance to win spot prizes and meet their sporting heroes.

The Mount Maunganui Weet-Bix TRYathlon will be at Arataki Park on Sunday, December 3, from 7am. Prizegiving is at 12.45pm.