A fartlek is a system of training for distance runners in which the terrain and pace are continually varied to eliminate boredom.

While counting calories is common, a new trend is taking health-tracking to extremes. But can you know too much about how your body works, asks Katrina Megget.

"Just because you're a yogi, doesn't mean you won't have an occasion for beer, and we're certainly interested in talking to that crowd."

A gym on Auckland's North Shore has been running classes for dog owners and their canine mates since January.

Including kids early in outdoors activities can be a challenge, but it pays health and happiness dividends.

Lorna Jane's ad for a "receptionist/fit model" to carry out administrative duties as well as help the design team fit garments caused outrage.

Eugene Bingham describes how running helps him find freedom - freedom to quit worrying and be happy.

"We all know exercise is good for our physical and mental health, but this data suggests that regular exercise may also help make you more productive."

A growing market in the online sale of human breast milk is creating a serious health risk, doctors have warned.

4 of the best learn-to-ride bike trails for kids to find their balance.

Use these tests to check whether you're as fit as you should be for your age, and learn what you can do to improve your fitness.

Danish man sets new world record for planking after holding gruelling position for four hours and 28 minutes.

What are electrolytes, how do they work, and why do we need them? A sport scientist explains.

Hugh Jackman has joined the 1000 pound club, proving that he is incredibly buff and may in fact be Wolverine.

Older women are more likely to take up exercising and stick to it if they are part of a small group guided by a personal trainer.

If you're feeling tired and run down, can exercise make you sick? And should you wait until you've completely recovered before putting those runners back on?

It's a pretty straightforward piece of equipment and you've been walking and running for how many years now? How difficult can it be to try a treadmill for the first time?

The recent death of a Facebook exec's husband highlights the dangers of using distracting devices while exercising.

Carroll Du Chateau meets yoga devotees and looks at how the ancient practice has become a multibillion-dollar business.

A pole dancing couple will become rivals this weekend in a battle of grace versus strength.

Besides improving your flexibility, the ancient practice apparently has another, rather unexpected, benefit, says Maxine Frith.

I'm someone who jogs most days and boasts to his friends that he's reasonably fit, writes Jack Tame.

Only the mastectomy scars beneath his pecs reveal that the New Yorker was, in fact, born female, beginning the transition from woman to man five years ago.

Trainer and former model ate junk food and piled on 40kg — in his bid to help eradicate global obesity.

Walking may be the best exercise but being a pedestrian carries risk in the big city.

But what use, really, are increasingly popular health apps like Fitbit and Jawbone that monitor our activity levels, heart rate and even sleep patterns?

If you're middle-aged or older and you work out, it's not too long before the question crosses your mind: I wonder if this could kill me?

Dwayne 'The Rock' Johnson is known for his great physique, but that doesn't come without a lot of hard work and massive meals.