Kiwi ultramarathoner Lisa Tamati, now 29 days into her 2,200km run the length of New Zealand, says her body is holding up well, despite early injury fears.

Lisa Tamati will run the length of the country - 2,200 km - in just 33 days. That's the equivalent of 52 marathons in just over a month.

Dry weather is forecast for the biggest ever Auckland Marathon this Sunday, with more than 13,500 runners and walkers lined up to compete.

Ben Ruthe, the reigning Auckland Marathon champion, describes 2009 as "hellish" for his family.

Some people take the Auckland Marathon quite seriously, but to Geoff Nottage it's "just a bit of fun".