Each week intrepid reporter Rachel Grunwell will try out a new form of exercise to bring you the lowdown.

What is it?

A room full of people on stationary bikes being coached for 90 minutes. In this case, the coach (also on a bike) is Stephen Farrell, New Zealand's fastest ironman from the 1990s.

What's needed? A bike with cleated pedals, a wind-trainer (your own or hired), cushioned bike pants, cycling shoes, water bottle, towel.

The experience: Stephen Farrell jokes he's got a cylinder of oxygen in case I need it after his class. To make sure I behave myself and work out properly, he's put me on a bike in between a military man, Roddy Hickling, and a swim coach, Patrick O'Connor. Farrell says he'll be on to me if he hears me bleat mid-class, "I've just got to get away to a really important meeting".


He tells me I ought to leave after an hour if it's my first time. Then he's back to being a joker, telling the class there's a journalist in its midst and "Shall we give her a nice time, or smash her?"

Hickling yells for the latter and then winks, saying he had to say this because he's from the military where he's been taught "train as you shall fight". Besides, he reckons I should prove Farrell wrong that I can hack it past an hour. So I prepare to be smashed.

Farrell is at the front of the class on his bike (practising what he's preaching). He giggled earlier, "I yell at them and they pay me".

He's got a near-full class, 40 people, and you can tell cyclists like and respect him. He's got 25 years' triathlon experience, as a coach and top competitor, and is the North Harbour Triathlon Club's head coach. During the mid 90s he was one of NZ's most formidable Ironman athletes. His best result was in 1996 when he placed 2nd; in 2004 he won the 40-44 age group and finished 11th overall. Last March he raced IMNZ for the 10th time and finished 1st in the 45-49 age group and was the 37th male. He also won the 2011 Air NZ Rarotonga International Triathlon. So you couldn't ask for a better coach.

At the start of the class, cyclists are chatting and sitting upright on their bikes. By mid-class most are hunched over their handlebars and are in race mode. Every so often, Farrell does a countdown to the next level of intensity. He tells us to aim for different numbers of revolutions (of the pedals) per minute (RPM) and yells out things like "use big gears!" and "now sprint!". Sometimes legs are alternated and used solo, but mostly two feet are flat-out during timed sets. The music blares. On the floor, sweat drips and later pools.

The cyclists, who range from beginners to professional athletes, pedal fast, then hard, adjusting the gears and pace to simulate racing up and down hills and on different terrains throughout the 90 minutes.

When they finish a set, they stop. Breathe. Recover. Then they're off again.

Hickling says the classes are "addictive" and reckons for every minute he works out with Farrell on a stationary bike it's equivalent to near twice the time on the road.

As an hour ticks by, Farrell looks my way. I'm now red-faced. I hang in there for 80 minutes of what my new military mate describes as a "a good hard grind". I'm smashed.

How much? $9 per session, $7 for North Harbour Triathlon Club members ($5 for juniors). Plus wind-trainer hire $8.

Worth it? This is amazing training to get cyclists in shape for big races, and especially good in winter to avoid the elements. No potholes plus a toilet stop can be made across the hall at a moment's notice. Cons include static scenery. But you can chat while you ride - some of the time anyway ...

Try it: Farrell's sessions at the Birkenhead Leisure Centre, Mahara Ave, Birkenhead, are on Tuesday and Thursday 6.30pm-8pm. Hour-long Saturday classes are also available. Ph (09) 419 0886 or email fitforfun@xtra.co.nz

Rating: 9/10