What do you get when you tie a piece of inch-wide flat nylon between two points?

"It's evolution in motion," a man calls out, the grin lighting his face as he gently and gracefully walks along a thin line suspended between two trees.

There's no chance to ask him what he means, he's focused on staying on the line.

"One kid said it's just like walking in heaven," says Ryan, jumping off and still buzzing from the enjoyment.

In a park on Burleigh's Esplanade, children laugh while they run, jump and take fairy steps across a network of 'slacklines'. The inch-wide webbing is tied between trees and close enough to the ground to climb onto.

But there's more going on than meets the eye.

"There's a direct outcome with slacklining," says Ryan Gittoes, possibly the first enthusiast to introduce the sport to Australia. "You express tension and the line wobbles, you relax and it stops."

"At any moment on the line your brain is firing on all cylinders, processing a massive amount of information coming in through different sensory inputs.

"It's a fantastic workout for cognitive and motor skills and for forming stronger links between these senses and the brain."

Stepping onto a line is initially a little daunting, but the fear is bizarre knowing there's only a matter of feet to fall. Within moments the only thought is to be calm, breathe slowly and find balance.

Slacklines don't have the bite of an inflexible tightrope; instead they stretch, bounce and move with the body.

Ryan talks through the four qualities he recommends you call on to find balance:

Focus; find a point to look at and establish balance and contemplate an internal point of balance - like the centre point of a pendulum;

Relax; and feel how the slackline responds to your body;

Grace and agility; the line invokes a response that's graceful or agile;

Will; summon the strength and determination to stay on the line.

"Life is about balance," says Ryan. "I think it's a natural state."

"As soon as you find it, there's a lightness, a feeling of wellbeing."

Slacklining is a huge phenomenon overseas, but little known outside climbing groups in Australia. It began 20 years ago in the rockclimbing community in the United States and has exploded into the mainstream in the last couple of years.

The kids (and adults) in Burleigh park can't get enough.

"If you've got a rock solid experience of balance that you can test and challenge, you can call on it in other parts of life," says Ryan, flexing the slackline under his feet before twisting into the air.

"Like riding a bike, once you start to slackline you only ever get better.

"It's easy to set up in the backyard to have fun with your friends, for sports training or rehabilitation, or a moving meditation."

Not only is slacklining good for you...it's pretty cool too. Around the world, practised slackliners have a few extraordinary tricks up their sleeves. Somersaults, twists and jumps, walking over obstacles and the highliners...literally taking the sport to a whole new level.

Slackliners take it seriously too, setting records for the longest lengths walked and creating new ways of slacklining.

Ryan is especially excited about the potential of the sport for kids with learning difficulties, and the benefits of working with balance.

Balance draws on three senses; vision, proprioception and the vestibular system.

Proprioception allows us to walk in the dark without losing balance. It's the awareness of where neighbouring parts of the body are in relation to one another and in space.

And the vestibular system, or balance system, sends information to the brain about the body's movements and position in space. In response, eyes and muscles adjust to keep the body upright and balanced.

"When you're balancing on a slackline, you're constantly moving, making small adjustments," says Ryan.

"You're strengthening your core and challenging your brain while you're working with the qualities of balance; focus, relaxation, grace/agility, and will."

Ryan takes the hand of a small participant and leads her gently along a line.

"If you want balance; bring it into your life," he says.

"Spiritually I think slacklining is about getting in touch with that centre and finding balance in a life full of positives and negatives, and demands on your time.

"And I think we all enjoy time when we are really present. When there's no distraction, and you're not thinking of anything beyond what you're doing in the moment."