U.S. researchers found taking three five-minute walks for every three hours spent sitting can reverse the harm caused to leg arteries.
There benefits remain even when the walks are slow, they say.
Sitting for long periods of time is associated with a higher risk of raised cholesterol levels and greater waist measurements.
This, in turn, can lead to heart disease, diabetes and stroke.
Earlier this year experts, said sitting down can be as bad for our health as smoking – and that inactivity is the fourth biggest killer of adults in Britain.
It is thought the average British adult spends up to 70 per cent of their day sitting down.
The new study found that when sitting, muscles become slack and do not contract to effectively pump blood to the heart.
Blood can pool in the legs and affect the ‘endothelial function’ of arteries, meaning they are less able to expand from increased blood flow.