Eric Murray, Olympic and world champion, can't remember the first time he used it; Lucy Spoors, up-and-coming New Zealand representative, hated it.
"Our sports teacher [in her first year at Christchurch Girls' High] was watching me. The whole time he said 'it's not that bad, only 20 more strokes, only 20 more strokes'.
"I was just hanging on. Initially I remember hating it because I looked at it as a punishment rather than a training tool."
Welcome to the world of the "erg", or indoor rowing machine. Think sweat, repetition, exhaustion, aches, floppy legs and tired minds, but New Zealand's best rowers wouldn't be without them.
Murray, four times a world champion and an Olympic gold medallist this year - became the world record holder for most distance covered on a machine in an hour late last year: 18,728 metres, his heart rate reaching as high as 201 beats a minute.
"That was a bit stupid," he quipped.
No self-respecting gym would now be without them; the Rowing New Zealand high performance centre at Lake Karapiro has lines of them. Go there most days in a season and you'll find the country's best relentlessly churning out the kilometres.
Where would rowing be without the indoor machine? It's difficult to quantify, but certainly New Zealand rowers are luckier than their counterparts in much of northern Europe. The deep winter freezes mean they spend hours on the machines, out of necessity. The flipside is it has probably made them more reliant, therefore able to make more of them than the outdoors-fortunate New Zealanders.
Before the rowing machine and its strong cardiovascular properties, rowers trained off water in much the same ways as other sportsmen and women, often running and cycling. Gary Reid, a single sculler at the Los Angeles Olympics and now owner of the New Zealand distribution of the hugely popular Concept 2 brand of indoor machine, remembers with rough humour the "old days".
"After doing a chunk on the water we used to do sprints up a hill. One guy fell down a pothole and just about wrecked his ankle, another had shin splints so could only pedal around on his bike and I ran like a baby elephant anyway. Jeez, I used to hate it with a passion."
Technological advances mean modifications are always around the corner. One example is the ability to link several machines side by side to simulate a race. Some models have the seat fixed, the foot stretchers sliding; others have both parts moving. Then there's the electronic componentry. As Reid put it: "It'll never stop. It's just progress and there are some seriously smart guys around."
Murray argues the case that the machine give as full a body workout as any piece of apparatus.
"As a training tool it's a great thing," he said. "Rowing is generally one continuous motion. If you can do that on the machine and transfer that on to the water then you're doing pretty well."
The indoor machine removes impediments such as crosswinds, choppy water and issues of balance. The hand movement differs slightly but it enables rowers to hone their stroke. And, as Reid put it, it makes a rower accountable. You can't hide; the numbers, time and distance put on the machine don't lie.
Each year there is a world indoor championship, initiated by a group of former American Olympic rowers at the start of the 1980s and contested in Boston.
Murray's world mark came out of a tradition started in 2005 by RNZ head coach Richard Tonks. He ends the pre-Christmas training programme with a one-hour row. Spoors, bronze medallist in the quad at the under-23 world championships this year, calls it "bitter sweet. You're breaking for Christmas, but first you're on it for an hour".
Murray had seen other rowers post their best efforts from around the globe, and fancied a challenge - "and I thought I'm pretty sure I could beat that".
Nothing beats being on the water but if you think it looks easy, hop on and go 2000m next time you're at the gym.
It is to be respected.
Yvette Corlett (nee Williams) took us back to her training sessions on the sandhills of St Clair beach; and we took a peek into Irene van Dyk's back lawn and the netball post where she has spent more time than she can recall, honing her goal shooting craft.
The Magnificent Six of Peter Snell, Murray Halberg, Barry Magee, Bill Baillie, Jeff Julian and Ray Puckett dominated NZ athletics through the 60s, due in part to a now legendary run through and around West Auckland; the P Class is a uniquely New Zealand boat and it has also proved the making of champions.