This year's most popular Christmas presents are making children fat and unhealthy, according to a new survey.
Kids would be better off if they were given gifts from the 1970s like Space Hoppers and Chopper bikes.
The poll asked PE teachers what they thought made kids unhealthy - and their top answer was favourite Christmas toys like games consoles and mobile phones.
Experts say children should spend at least 30 minutes a day doing physical activities, like walking or running.
The survey also found that PE teachers say 85% of their pupils are not as fit as they should be.
During the 1970s a number of toys which encouraged outdoor play were hugely popular such as the Space Hopper (1971), rollerskates (1972), the Chopper bicycle (1973), stunt kites (1976) and skateboards (1977).
Poll spokeswoman Professor Kate Sullivan said: "We have seen an increase in children spending less time playing outdoors and more time in front of the TV, playing computer games or transfixed by the text messages on their mobile phones.
"I fear that our future generations will be computer and electronic whiz kids, but too overweight and lazy to move out of the confines of their hi-tech, globally-wired bedrooms."