From a distance, it looks and sounds like any other children's playground. There are all kinds of apparatus populated by screaming, excited kids. But step closer and you see a difference.

First, there's an adult trainer in charge.

Second, the children are not jumping on the equipment in random fashion, but are following a series of organised exercises.

And third, you notice their age. They are all under six years old; the youngest is not yet one.

Purposeful play

This is the new open-air playground in the city of Treviso, just north of Venice.

It cost a quarter of a million dollars (£170,000) to build and was designed by scientists from the University of Verona, to help keep obesity at bay by making play purposeful.

"This is not sport for babies," says one of the organisers, Enrico Castorina. "It's about movement, co-ordination and balance."

Image caption Claudia, 6, tries the assault course

In this land of pasta, parmesan and panini, the scope for weight gain is abundant.

Children are exposed from birth and it shows in their girth.

Obesity rates in Italian children are among the highest in Europe. Around a third of boys and girls are classified as obese by the International Association for the Study of Obesity.

Assault course for children

The park is divided into zones.

The first zone is a miniature assault course for kids.

But instead of sergeant majors barking orders at raw recruits, you have Alexandra, a professional trainer, who gently encourages the youngsters to tackle the route.

The assault course is about 50 metres long and takes just a few minutes to complete.

Six-year-old Claudia says she loves it and wants to go again.

Part-funded by the government, local businesses and also by Italy's Benetton clothing family, in effect it's a gym disguised as a playground.

Testing balance and strength

In another zone there's a slide and at the end of it is a row of small tree stumps sticking out of the ground.

The aim is to get the children to career down the slide, then race off to walk over the stumps.

Some fall off onto the grass.

There's no harm done, but the children are asked to try again.

Mums like Haylee Ahu approve of the early start to organised sporting activity.

"The aim is to instil the message that mobility is good from a very early age, from zero, in fact" Enrico Castorina, Fitness park organiser

"It's been well organised and thought out," she says, "and I like the way my daughter's motor skills are being developed. It's great."

On one side of the park, you can hear the creaking of a giant horizontal rope.

It's rocking back and forth with children trying to hold on.

Here, balance and strength are being tested.

It's another device that mixes games with gain.

To the children, it's just play

The organisers say the children have fun, unaware there's science behind it.

But is it all taking place too young?

Should toddlers, even babies, be taking part in what amounts to training, I asked the organiser Enrico Castorina.

"It's never too young to think about movement," says Enrico. "The aim is to instil the message that mobility is good from a very early age, from zero, in fact".

And mum Haylee agrees.

"I think it's a good idea to start them thinking about activities like this from an early age. To them it's just play. It's not a normal park where there are just swings and roundabouts. Here, it has a point."

Image caption Trainer Alexandra helps a child balance on a log

As Claudia reaches the end of the assault course, she taps a small bell to signal she's done it.

There's a wide smile on her face that reveals her satisfaction, perhaps the best kind of endorsement.

There are plans to start a chain of these free parks across Italy.

Playgrounds are becoming sporting grounds, in the pursuit of an even longer active life.