Hamilton triathlete Mikayla Nielsen may not be at her fittest, but she's still ready for her first race of the season tomorrow.

The former junior world champion will line up in the first event of the Contact Tri Series in Rotorua tomorrow, looking to put a disappointing world title defence behind her.

In October Nielsen was forced out of the junior women's race in Auckland after suffering from hypothermia while in the lead bunch on the run.

While she has some big goals to achieve later in the summer, Nielsen is looking forward to starting well.

"I'm really looking to have a good race where I'm satisfied at the end and hopefully be near or at the front," she said. "Being my first race of the season, it's a good chance to see where I can make improvements for the Youth Olympics coming up in January.

"I came off a long break a couple of weeks ago so I'm just getting back into the speed work. I wouldn't say I'm super fit at the moment but you never know, I might just surprise myself this weekend, especially on my new bike from Specialized."

The competition is a seven-leg series, with Whangamata the second race on the calendar on January 3, before the series heads to Christchurch, Wanaka, Kinloch, Takapuna and Wellington - the last race on March 9.

Tomorrow's race will be combined for the first time with the popular Rotorua Half Ironman in and around Lake Tikitapu (Blue Lake) and a number of former and future stars will line up.

"I have raced there before and remember it being freezing and rather hilly," Nielsen said. "The run would be my favourite part of this course: bit of road, interesting off-road tracks and a beach run in the middle/end. It will be great with the warmer temperatures on Saturday, I'm sure."

Nielsen will compete in the standard distance race, while former world number one Sam Warriner, 41, continues her return to the sport after taking time out to start a family as she races in a sprint distance team tomorrow.

Also lining up is Hamilton's Maddy Brunton - a former Rotorua winner - who has focused on her studies in recent times.

In the men's race the standard distance is highlighted by the presence of well performed Graham O'Grady (Kinloch), fresh after wins in the Taupo Half Ironman and Tinman events.

Race distances on offer tomorrow range from the Contact 1:2:1 for the children to the Contact 3:9:3 for beginners and the sprint and standard distances races for those looking for more of a challenge.

The day will begin with the Rotorua Half Ironman, at 6.25am for men and 6.30am for women.

Entries are still being accepted online at www.triseries.co.nz or can be done today at the Holiday Inn in Rotorua from 4pm-8pm or late registration is available tomorrow at Blue Lake between 5.30am and 7am.

- © Fairfax NZ News