Sixty years ago, researchers found that bus drivers had twice as many heart attacks as bus conductors. The difference was that the conductor was on his feet all day, whereas the driver was sitting down.
Nowadays, adults in the UK commonly spend seven or more hours a day sitting down, and this tends to increase as people get older. Long periods of sitting are typically associated with an inactive lifestyle, which is a risk factor for heart disease, dementia and diabetes.
It’s a vicious cycle because the collagen around your tendons and ligaments tends to harden when the joints aren’t moving, and the postural muscles around your trunk gradually get weaker. This reduces your flexibility and makes you more likely to strain your back or shoulders when you bend or lift. Without the need to support your weight, your leg bones become more porous and blood tends to pool in your ankles, which can lead to varicose veins and even deep vein thrombosis (dangerous blood clots in your veins).
The good news is that a 2016 analysis of studies of over a million people found that you can completely counter the negative effects of a desk job by doing 60 to 75 minutes of moderate physical exercise every day. Standing or walking during meetings and standing while talking on the phone are both good ways to start reducing your daily sitting time.
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