Video games, televisions and computers have all contributed to the increase in childhood obesity, says New Idea's fitness expert and Ironman legend, Guy Leech.

The number of overweight children has more than quadrupled in one generation and that's frightening. Experts are quick to blame junk food, but screen-time habits are also a big part of the problem.

Everything today is geared towards making life convenient and easy - microwaves, drive-through fast food, remote-controlled technology, home delivery and escalators, to name a few.
I embrace this technology, as long as the laziness it promotes is balanced by activity.

With the arrival of TV in 1956 and home computers and electronic games in the 1980s, screens have become a big part of everyday life.

'By the time the average person reaches 75 they will have spent more than 12 years watching TV,' says British psychologist Dr Aric Sigman. 'The average six-year-old will have watched almost a year's TV. That's not good for a developing brain.'

Dr Kate Ridley from Flinders University studied the habits of more than 1000 teenagers. She found boys spend 31 per cent of their time in front of screens, while girls' daily screen time is 23 per cent.

To combat this, Dr Ridley suggests encouraging your children to go to bed earlier. 'And if parents give their children an 8pm curfew on all screens it reduces daily screen time by 45 minutes,' she says.

However, a little TV time can be positive for kids. Studies in the UK have found that when watched in moderation TV can aid speech development in two to five-year-olds. It also helps to educate young people about key social issues.

'Television, where used as a focus for discussion among peers or to promote parent-child interaction, can be a positive thing,' says Dr Kevin Browne from the University of Birmingham. 'What we need to be wary of is watching TV in isolation.'

My wife and I allow our eight-year-old daughter Paloma one to two hours of screen time a day.

My advice? Be vigilant. Do you know your family's screen habits? Take control of the remote, mouse and joysticks, and make sure inactive time in front of a screen is balanced by active time outside.

TAKE CONTROL

• Don't leave the TV on as life's backdrop. Turn  it on to watch something, then turn it off.

• Restrict total screen time to no more than two hours a day for adults, one-and-a-half hours for teenagers and nothing for children under two.
  

• Remove TVs from kids' bedrooms. This way, you have some control.

What is screen time?
'Screen time' includes watching television, videos or DVDs, using computers, playing Xbox, PlayStation, Nintendo, Game Boy and all hand-held video games.

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