Did you know the average Aussie spends about 9 hours a day sitting down?
Even if you're getting your recommended daily exercise, researchers are now saying that it doesn't cancel out all of the negative effects of sitting too much.
When you're sitting for a long time your muscles switch off and your body isn't as good at processing fats and sugars.
So, if you've just eaten your blood sugar levels can stay high for hours.
In the long term it can lead to some pretty nasty problems like obesity, diabetes and heart disease.
That's why schools like this one are trying to get kids off their chairs as much as possible.
Year 4 think it's fun and it helps them to concentrate for longer.
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