Murray Fleming knows he will still be amazed even after 10 hectic years involved with New Zealand's maddest endurance race.

As organiser of the annual Burgen Tough Guy and Gal Challenge, he's watched it mushroom from 432 people at the first one at Rotorua, to 42,000 hardy souls who have braved the mud and mayhem since.

Events were also now held in Auckland, Wellington and Palmerston North.

Fleming has seen competitors of all shapes and sizes, dressed in everything from tutus to superhero outfits - and he still managed to be surprised yesterday.


"Right from the beginning, the bottom line has been, this has to be a lot of fun," he said.

Yesterday more than 1700 athletes fought through the Auckland challenge at the Woodhill Sands Equestrian Events Centre. About the same number were expected today.

"The weather was outstanding and the rain earlier in the week made for near perfect conditions as the track was the dirtiest and muddiest ever," he said.

Fleming said two twisted ankles were the worst of the injuries. "We also had the most bizarre range of costumes I have ever seen."

Personal trainer Essendon Tuitupou runs a bootcamp for more than 200 people in South Auckland - 140 of them signed up with the fun event as their ultimate goal.

"Most men have gone for the 12 kilometre race and most women opted for the 6k," said Tuitupou. "We also have some really big guys doing the 6km, including one who weighs 113kg, so anyone can do it with the right help and support."

Yesterday's Auckland leg also attracted members of the Breakers basketball management team and a host of Breakers' Academy players.

One race favourite missing was Mission Bay firefighter Josh Harrison, who had triumphed at two Tough Guy events and won the Sky Tower Challenge last year.

Harrison fractured a leg after being knocked off his bicycle in February by a hit and run driver while on his way to work in Otara, but said he hoped to be fit for upcoming Tough Guys in Palmerston North and Rotorua.