We all know that physical activity is important for good health—regardless of your age, gender or body weight, participating in daily physical activity can improve your quality of life and dramatically reduce your risk of death and disease. But let’s say you meet the Canadian physical activity guidelines by exercising for more than 150 minutes per week (a goal which is achieved by just 15% of Canadian adults), that still leaves 15-16 hours per day that you are not being active. Does it matter how you spend those non-active hours, which make up more than 90% of your waking hours? For better or worse, new evidence suggests that it does.
For example, a recent study in Medicine and Science in Sports and Exercise looked at the risk of death in a group of 17,000 Canadian adults over a 12-year period. The individuals in the study who sat the most were roughly 50% more likely to die during the follow-up period than the individuals who sat the least, even after adjusting for age, smoking, and physical activity levels. In other words, regardless of a person’s body weight or how much they exercised, sitting too much dramatically increased their risk of dying during the study period. This finding is far from unique – there are now dozens of studies in both adults and children suggesting that irrespective of your age, body weight, or level of physical activity, sitting increases your risk of obesity, heart disease, diabetes, and even death. And keep in mind that Canadian adults and children sit for more than 60% of their waking hours – the average Canadian kid sits for more than 8 hours per day! Not surprisingly, sedentary behaviour is quickly becoming an important public health issue.
Fortunately it’s not all bad news – 2 new studies suggest that simply breaking up sedentary time (for example, standing to stretch your legs or walk to the washroom) can dramatically reduce your health risk. For example, an Australian study (which has recently been confirmed in a larger American study) suggests that regardless of how much you sit on a regular basis, simply taking more frequent breaks is associated with lower waist circumference, and improvements in blood lipids and glucose tolerance. So even if you have to sit a lot, simply taking frequent breaks to stand and stretch your legs may reduce your overall health risk.
So, what to do if (like me) you spend your workday sitting in front of a computer? Luckily, you have a few options. Many office tasks don’t have to be done sitting down – that’s just the way we tend to do them. Things like stapling and making phone calls (especially conference calls) can be done just as easily while standing as they can with your butt in a chair. Rather than having a sedentary chat with co-workers during lunch, consider going for a short walk. The key is to take a step back and look for opportunities to get out of your chair as often as possible.
Depending on your office layout, you may also be able to use a standing desk (I’m writing this post standing in front of a $30 laptop desk that’s propped up on a pile of textbooks), or fit a small pedal machine below your desk. Some people have even set themselves up with a treadmill workstation so that they can walk all day! We don’t know for certain whether a standing workstation can reduce your long-term health risk, but it is definitely plausible, and worth considering if you are concerned that you may be sitting too much. If you are going down this route though, do make sure that your setup is ergonomically correct, and that it allows you to sit when necessary (when I use my standing desk I tend to work while standing for an hour or so, then spend a half hour sitting down to let my back rest). And at home, do everything you can to limit the amount of time that you and your children spend in front of TV and computer screens (the average Canadian kid spends more than 7 hours in front of a screen every day – yikes!). It’s almost impossible to be anything but sedentary when you’re watching a screen – turn it off, and you’re moving in the right direction.
And finally, if you absolutely have to sit for a period of time, try to take breaks whenever possible. This can be as easy as drinking plenty of water, which will force you to take a break every hour or so (remember, the more breaks the better). And when you have your washroom break, why not go to the washroom on another floor or in a different part of the building? Ditto for using the photocopier machine. If you are watching TV, commercials are an excellent excuse to stand up and move around – an easy way to get more than 15 minutes of activity during an hour of TV viewing (but seriously, turn off the TV whenever possible). These are little things that don’t take much time, but can really add up over the long term.
For more on the health impact of sedentary behaviour, you can see our 5-part series on Obesity Panacea. Or to learn about Canada’s new Sedentary Behaviour Guidelines for children and youth, as well as tips on how to reduce your child’s sedentary time, click here.