OK it is now “official” – being sedentary does actually kill you. The negative impact of a sedentary lifestyle on our health has been observed for many years but it has now been clearly shown and quantified.
An Australian study of 8800 people over six years found those who spent four hours or more watching TV each day had a 46% higher chance of dying and were 80% more likely to die of cardiovascular (heart) disease than those watching two hours or less per day. There was a steady increase in risk of death of 11% per hour spent in front of the TV. A study of 123,000 Americans over 14 years showed a 20% (for men) and 40% for women, difference in death rates between those who sat for over six hours per day versus those sitting for less than three.
Another American study showed people who were sedentary found it harder to lose weight even when taking in the same amount of calories. Small incidental movement (not formal exercise) like taking the stairs had a significant effect. In this study the groups did the same amount of “exercise”. It was the group that did more movement in their daily life, which had fewer problems with weight.
No doubt the studies can be criticized but the key findings confirm what we have really known for a long time.
The human body is designed to be active. Until fairly recent times this was not optional. To eat you needed to catch or gather food. To get from place to place you needed to walk. Most work was physical. Today we have so many labor saving devices that most of the “incidental” movement and exercise we got even one generation ago is gone.
Thirty years ago you needed to get out of the car to open your garage door and, dare I say it, get up off the couch to change the TV channel. Now it is important to note that sitting in front of a computer or video game or even sitting reading is still being sedentary so it is not the TV as such that is the issue.
Interestingly, and this is a new finding, even those who did some regular exercise were still affected by being sedentary for long periods. There are metabolic changes that occur in our bodies whilst we are “still”, that amongst other things, slow down the burning of fat. Sugar and cholesterol metabolism is also affected.
So whilst regular exercise remains vital for your health, being sedentary for long periods is a separate risk factor in poor health. The two do not seem to cancel each other out. “Exercise is not a perfect antidote for sitting” says Marc Hamilton an inactivity researcher at Pennington Biomedical Research Centre (quoted in The New York Times).
The good news then is that the answer to prolonged inactivity is fairly simple. Here are some simple ideas to incorporate into your life.
- Take the stairs instead of the escalator or lift.
- Park in the furthest rather than nearest spot at the mall.
- When working at your computer, get up and wander around for a minute every 30 minutes.
- Limit your TV time to two hours per day maximum. Get up and wander around the room during the ads. Get up to change the channel.
- Do some housework each day. Chores like ironing, hanging out the washing, even cutting vegetables are being “active.”
- See what you can do standing instead of sitting. The simple act of standing uses muscles that sitting doesn’t.
It is great when medical science catches up with what we all really know anyway. Movement is a bit like medicine but without side effects or cost.