Encouraging young people to do strength-based exercises -- such as squats, push ups and lunges -- could play a key role in tackling child obesity, research suggests.

Taking part in exercises that cause muscles to contract, and strengthen muscles and bones, was found to reduce children's body fat percentage.

The findings also suggests an increase in muscle mass -- gained from strength-based exercises -- could help boost children's metabolism and energy levels.

The effects were small but meaningful, prompting calls for further research to investigate how resistance training could treat and prevent the growing issue of child obesity.

Researchers at the Universities of Edinburgh and Dundee examined the findings from a number of studies that explored effects of resistance training on body weight for children aged nine to 18 years.

They found that resistance training decreased body fat, but had no overall effect on other measures, including lean muscle mass, body mass index and waist circumference.

This is the most extensive review so far of resistance training's impact on young people.

Research from 18 studies across eight countries was examined, including the US, Australia, and Japan.

Helen Collins, a PhD student at the University of Edinburgh and Sport and Exercise Scientist at the University of Dundee, said the results show the positive effect resistance training can have on maintaining a healthy weight and reducing body fat for young people.

"Treatment, and more importantly, prevention, of child obesity is a growing concern. Our findings highlight the need for more robust research into the role strength-based exercises can play in helping everyone make healthy life choices and be more physically active."