Last updated at 08:41

Martin visits kids who want to lead healthier lifestyle

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We all know how important exercise is, but according to a top medical journal almost half of seven year olds aren't getting enough.

The findings come at a time when doctors say the UK has the highest rate of child obesity in Western Europe.

Being obese can lead to really serious illnesses like type-2 diabetes, asthma and breathing difficulties.

But Martin has been to Leeds to meet a bunch of kids determined to lead a healthier lifestyle…