Enduro means he's sometimes hanging to his GasGas 300EC two stroke bike for five to six hours at a time across 200km over "some pretty gnarly terrain".
"It's quite a long day," he says in his understated way.
This year the national champ series has been wound down to five rounds from six in previous years, but that doesn't mean there's not still a whole heap of events to take part in. Those events take place in stages, similar to car rallying, over farmland and forest tracks.
Speed thrills, but it's literally cliff hanging stuff sometimes - a bruising, bumping, bone breaking ride on its smoothest of runs. The riders have to be supremely fit but it's not all about who can hang on the longest, or whose bike can best handle the beating. This sport takes brains, as well.
"It's very physically demanding but you have to keep your head because there's a lot going on," Nield says. "It's about skilled riding on gnarly terrain, not just speed."
Here, there's not much money in the sport although Nield's lucky to have the GasGas sponsorship for his bike, some support from Kiwi Rider magazine and help from a few other motorsports areas.
Overseas there are quite a few people making a good living from enduro.
"In New Zealand it's tough trying to work enough to afford to race, and race enough to stay at the top," He says.
But whenever they can Nield and his fiance and "teammate" Sianella Owen pack up the bike and a truckful of weekend stuff and head off for an endurance feat.
He's the gun rider, she rides shotgun.
"I have my own bike but I don't compete. I organise and I bake," she says.
Nield says the support Owen offers is invaluable; there's a lot of planning goes into taking part in the sport that throws its competitors all over the country.
"It's been a great way to see New Zealand and we look forward to doing more overseas travelling with it," Nield says.
Coming up is the National Enduro third round at Whangamata on April 14, the Dirt Guide Cross Country round one in the Waikato on April 28, the National Enduro round four Waimiha on May 5, the Dirt Guide Cross Country round two in South Waikato on May 14, and more rounds later in the year.
A couple of weekends ago Nield was one of a big field in an event called City Scramble at the Westhaven Marina in Auckland. It was a short course with "extreme" qualities - shipping containers, piles of boulders, heaps and hills.
The public loved it, a dirt bike spectacle in the concrete jungle, not at all tame.
In June Nield and Owen plan to be at The Erzbergrodeo in Austria, and back for The Roof of Africa 2012 in November.
Nield talks, obviously moved, by the experience last year in Lesotho. There, they were in the back of beyond, he says, in really tough country - not the green hills of home, certainly.
The people were poor, living in mudhuts, but when the guy from Northland would take his bike out into the wilderness for his practice runs, and the locals saw the New Zealand stickers, they would wave and smile and call out greetings to the "Kiwi".
Nield and Owen live at Pakaraka and his work as a self-employed builder takes him all over Northland. He's currently knocking an old cowshed on their property into a workshop, where he'll supplement his income by another of his passions, working on bikes.
When he can, Nield puts as much back into the sport as possible.
Nield says he started off "slowly" in junior motocross, and was into the serious racing at 16.
"It's a great way to occupy young kids," he says.
"Off road dirt bikes are very good at keeping them out of trouble or off the road and giving them a lot of fun and confidence."
