If you sit at your desk all day but consider yourself to be relatively healthy because you regularly go to gym, you may want to carry on reading. A recent study found that sitting for eight hours or more per day significantly increases your risk of death, regardless of your body mass index (BMI) and whether you do any physical exercise – and the more you sit, the greater your risk. This may come as a shock if you’re slim and trim, and otherwise pretty active. What’s even more shocking is that this effect was seen in healthy people as well as those with existing heart disease or diabetes. Overall, the researchers found that 6.9% of all deaths in the study participants could be attributed to prolonged sitting. While this may not seem like a lot, you might think otherwise if you or a loved one is affected.
Prolonged sitting has become a prominent problem in today’s society, where adults can easily spend two-thirds of their waking hours being sedentary. Now you may say that you’re safe because you don’t sit much at work. But you may nevertheless sit more than you think – try calculating all the hours you spend sitting in your car and relaxing in front of the television. Both of these sedentary behaviours have been shown to substantially increase the risk of dying as a result of heart disease.
But an increased risk of death isn’t all you need to worry about. Sitting for much of the day has been linked with a greater likelihood of experiencing breathing difficulties and chest pain, severe tiredness, bowel and eyesight problems, and depression. Back, neck and shoulder pain is also a common consequence of sitting for long hours, as is poor posture – all of which may explain the bad mood that’s often reported by people who spend most of their day sitting at their desks. What’s more, prolonged sitting increases the risk of type II diabetes and obesity (both of which in turn increase the risk of illness and death), and has even been linked to a greater incidence of cancer.
So why is prolonged sitting so bad for you? It’s been hypothesised that the lack of muscle activity impairs your metabolism, which results in an increase in circulating levels of bad fat, a decrease in good fat and poor glucose uptake. Sitting for hours at a time also diminishes the health of your blood vessels, and both factors together increase the risk of disease, especially heart disease. It’s also been suggested that this physiological effect isn’t simply the opposite of what happens during exercise, but rather a different￼process altogether. This explains why prolonged sitting is so unhealthy even in young, healthy and fit people, not just those with pre-existing diseases.
STANDING UP FOR BETTER HEALTH
Before you quit your job in a panic and start contemplating your chances of becoming a professional athlete, know that you can take steps to protect yourself from the ill effects of prolonged sitting. Although research has shown that sitting for much of the day increases the risk of death even in regular exercisers, this doesn’t mean that you should cancel your gym membership – exercise does have a protective effect if you meet the recommended minimum of 150 minutes of moderate-intensity exercise per week. While it doesn’t negate the dangers of prolonged sitting, doing a moderate amount of exercise does lower associated health risks. This is in stark contrast to a complete lack of exercise, in which case sitting for as little as four hours a day substantially increases the risk of death. Getting regular exercise is especially important if you already have heart disease or diabetes and are sitting for long periods of time, as prolonged sitting is even more dangerous in this case.
It’s important to note, though, that even regular exercise can’t completely compensate for the detrimental effects of excessive sitting. Because of this, prolonged sitting should be considered a health risk in itself. This means that you should make every effort to reduce the time you spend sitting down or reclining. But whether you’re sitting for four hours or 11 hours a day, and whether you’re otherwise physically active and healthy or not, the real danger lies in the uninterrupted nature of prolonged sitting – this seems to be the trigger for the dangerous metabolic consequences of prolonged sitting. Fortunately, studies show that this effect can be reduced by regularly interrupting long stretches of inactivity with some form of exercise. This means that there’s much you can do to improve your health even if you have to sit at your computer all day.
In addition to reducing sedentary behaviours in general, it’s important to take regular breaks from sitting. Research shows that frequently interrupting long sedentary stretches results in better health outcomes – including heart and metabolic parameters, waist circumference, aches and pains, and even mood – regardless of the overall time spent sitting and the level of physical activity. But you don’t have to run around the block to reap these benefits. Simply standing up for a few minutes every half an hour or so may just do the trick – although it’s not yet clear exactly how much sitting is too much, and how often you need to interrupt a sitting bout to get the most benefit. However, you can introduce activity into your workplace by making a point of standing up when you’re on the telephone, for example, and making an effort to walk to your colleague’s desk rather than communicating electronically. Getting up frequently when you’re relaxing at home is also a must.
CHANGING YOUR ROUTINE
The key to success is making these breaks from sitting part of your routine – that way you won’t even have to think about it. At first you may need to set an alarm to remind you that you need to get moving, but in time you’ll do it automatically. And while your colleagues may initially look at you askance, they’ll soon get used to your strange antics and may even be inspired to follow suit. Spreading the word about this seemingly innocuous health risk is vital to prevent serious illness and even death. Unfortunately, in today’s world, eating healthily and exercising just aren’t enough anymore – limiting the amount of time spent sitting must be included as part of a healthy lifestyle.
1 van der Ploeg HP, Chey T, et al. Sitting time and all-cause mortality risk in 222 497 Australian adults. Arch Intern Med. 2012;172(6):494-500
2 Dunstan DW, Howard B, et al. Too much sitting–a health hazard. Diabetes Res Clin Pract. 2012;97(3):368-76
3 Warren TY, Barry V, et al. Sedentary behaviors increase risk of cardiovascular disease mortality in men. Med Sci Sports Exerc. 2010;42(5):879-85
4 Pronk NP, Katz AS, et al. Reducing occupational sitting time and improving worker health: the Take-a-Stand Project, 2011. Prev Chronic Dis. 2012;9:E154
5 Rutten GM, Savelberg HH, et al. Interrupting long periods of sitting: good STUFF. Int J Behav Nutr Phys Act. 2013;10(1):1