The heat is on literally for Joanna Lawn when she tackles the Ironman 70.3 World Championships in the caldron of Las Vegas on Sunday.

The seven-time Ironman New Zealand champion is one of 30 elite women to tackle the 2km swim 90km bike and 21km run championship with temperatures expected to top 40°C.

After five years based at Clearwater in Florida, the world championship has been moved to Las Vegas where the extreme heat along with some testing climbs on the bike and run will make for a significantly tougher assignment.

Lawn is one of four New Zealand professionals to qualify for the world championship along with veteran Bryan Rhodes, Perth-based Guy Crawford and US-based James Cotter.

While the Aucklander specialises over the full Ironman distance, the conditions and tough terrain is expected to play more into her hands.

"It's reported to be a very tough course with very challenging conditions," said Lawn from her training base at altitude in Boulder, Colorado. "One reason why I wanted to do this race was because of the terrain and that it is expected to be a strength person's course.

"Of course it will still be super fast and so I hope I have some fast twitch fibres on the weekend."

Lawn secured the final qualifying place in next month's Ironman World Championships in Hawaii, after confirming her spot in the 70.3 worlds more than a month ago under the new qualifying points system introduced for both events this year. Accordingly she has gone down a different track with her preparations.

"I didn't know if I would make it to Hawaii so really all my training has been aimed at this 70.3 distance instead. The preparations have gone really well. It is something that is a bit different and I have really enjoyed the training which has been more aimed at quality than quantity."

She is not looking ahead to Hawaii yet, but said that she would often look for a blowout over this sort of distance a month out from the Ironman in any case.

"I think it fits perfect in timing for Hawaii. It is going to be used as a very hard simulation. But I have to remember that this weekend is going to be a very, very challenging race. I will have to be smart and get out of it what I need in terms of Hawaii."

Lawn has enjoyed an excellent season, winning three times over the 70.3 season at Port Macquarie, Western Australia and Korea, with her new-found speed on the run put down to a return to her old coach, Chris Pilone.

The New Zealanders qualified for the Ironman 70.3 World Championships are:

Professionals

  • Jo Lawn
  • Bryan Rhodes
  • Guy Crawford
  • James Cotter

Age Groupers

  • Katie Blampied (Hong Kong, 30-34 years)
  • Mark Blampied (Hong Kong, 30-34)
  • Malcolm Geluk (Qatar, 40-44)
  • Jenny Gowans (UK, 35-39)
  • Jamie Hunt (Melbourne, 35-39)
  • Marie Kirton (UK, 30-34)
  • Jared Preston (USA, 40-44)
  • Ricky Simonsen (Auckland, 40-44)
  • Werner Stebler (Waiheke Island, 60-64)

For full coverage see www.ironman.com.