Most British schoolchildren are not getting the 60 minutes of daily exercise recommended for good health, a charity says.
Only one in eight (13 per cent) get the right amount of exercise, while 30 per cent do less than an hour each week.
The British Heart Foundation (BHF) surveyed more than 1,000 children aged eight to 15 to launch its Food4Thought campaign.
Overall, 78 per cent were unaware of the recommended daily amount of exercise they should be getting, with 30 per cent saying they "can't be bothered".
One in five (20 per cent) said exercise was "a chore" that was only needed by people who are overweight.
Meanwhile, 55 per cent)of youngsters admitted spending an hour or more a day texting or chatting to their friends, or visiting social networking websites.
Experts have predicted that two thirds of all children will be overweight or obese by 2050.
Dr Mike Knapton, director of prevention and care for the BHF, said: "We have a generation of kids growing up who have a shockingly blase attitude towards exercise and being active."
The charity has launched an Ultimate Dodgeball challenge in UK schools.
Dr Knapton said: "Ultimate Dodgeball is a great way to get children interested in sport and physical activity - young people need to switch off their square eyes and get in the habit of exercising now."
Athlete Sally Gunnell is backing the campaign.
She said: "As a mum, I know how children can benefit from being active.
"It's something that all children should enjoy as part of a healthy lifestyle and is also a great way to socialise with friends.
"Children's sluggish attitude towards daily exercise is worrying and it's great to see the BHF thinking of new ways to get them intrigued and active again."Reuse content