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I recently was e-mailed this link: Sitting down is killing you.

Apparently this is based on a medical study and much of what is said in this range of adverts campaigning against sitting down makes sense and they do cite quite a few references. However, this particular campaign just seems a little bit too over the top for me. I'm wondering how much of it is accurate and how much is inflated to get a reaction out of the public.

Maybe I'm reading too much into it, but the figures they give in these ads and the way it's portrayed makes it seem like sitting down as most of us do in the average desk job is going to kill you much quicker than I can accept as plausible.

For instance I can agree that the human body wasn't designed to sit down for 8+ hours a day. But if I eat healthy and still go to the gym three times a week and stay reasonably mobile while not at work, can it be that dangerous? This particular range of ads even goes as far to suggest that even exercising doesn't lower the health-risks that the evil chairs are contributing by much. I find that very hard to believe.

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    Now who came up with the brilliant idea to put the references as text embedded in an image? Couldn't bother going through the references, so I'll just post some comments: The obesity thing doesn't distinguish correlation from causation. It could equally well be that obese persons sit more because they get exhausted easier. Again, this could perhaps be refuted by looking at the sources. "How sitting wrecks the body": The insulin one seems like a scare tactic. After 24h? Do they mean that happens if you sit for 24 hours straight? Then that's hardly a problem at all! – David Hedlund May 16 '11 at 12:25
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    "Get off the couch": This one is making weird arithmetic calculations on ordinals. It compares the groups "3 hours or more" with the other groups. We don't know whether the effect starts at three hours or somewhere further out along the "or more" axis. The graph seems to be drawn from the statement, and not the other way around. It is misleading in how it starts at 50, and already at 6 hours it is very close to 100%, which makes the graph look very much like a misplaced extreme extrapolation from other data. – David Hedlund May 16 '11 at 12:30
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    Furthermore, a lot of the graphics comment on how obesity has increased, but levels of activity has stayed the same, implicitly blaming all the sitting. The article doesn't comment that consumption has been increasing, and is a more likely correlate than sitting down. As someone points out in comments, one factor that can explain the link between age and likelihood of death is simply that old people sit down a lot, and are also more likely to die within any given time frame. Here, old age is the causation of both the sitting and the dying, the sitting does not cause the dying. – David Hedlund May 16 '11 at 12:38
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    @DeVil: it is always a fun mental exercise to try and figure out what could have been done to arrive at the different claims they're making in any presentation of statistics. This one doesn't upset me terribly because standing up occasionally is probably a whole lot better, but of course, using scare tactics to achieve that goal is not ideal. Having people vary their position based on a sound and informed decision would be preferable. If this leads to people standing up all the time rather than varying, they should be aware that's not very healthy either. – David Hedlund May 16 '11 at 12:43
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    The whole article just looks like another example of data mining gone wrong. Based in the percentages of people who die in their sleep, we should all stop that too, according to their logic. – Monkey Tuesday May 17 '11 at 2:07
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As it turns out, sitting for long periods of time seems to be associated with many adverse side effects.

  1. The University of South Carolina did a study on the effects long-term sitting has on cardiovascular health. They found that over a period of 21 years, men who reported being sedentary for more than 23 hours per week had a 64% greater risk of dying from cardiovascular disease.

  2. NPR commented on another study done by Northwestern University where the amount of exercise did not offset the damage done by sitting for long periods of time. Surprisingly,

...for people 60 and older, each additional hour a day spent sitting increases the risk of becoming physically disabled by about 50 percent — no matter how much exercise they get.

  1. Another study by Toronto Rehab, later published in the Annals of Internal Medicine found that

the amount of time a person sits during the day is associated with a higher risk of heart disease, diabetes, cancer, and death, regardless of regular exercise

So what can we do about this if exercise does not seem to help? The key seems to be breaking up long periods of sitting with short, intermittent periods of activity.

The University of Missouri says that 10 minutes of walking after a long period of sitting is enough to reverse the vascular damage caused by inactivity.

As a parting thought, in their question, DeVil said:

...I can agree that the human body wasn't designed to sit down for 8+ hours a day. But if I eat healthy and still go to the gym three times a week and stay reasonably mobile while not at work, can it be that dangerous? This particular range of ads even goes as far to suggest that even exercising doesn't lower the health-risks that the evil chairs are contributing by much. I find that very hard to believe.

I think the inactivity physiologist Marc Hamilton sums it up well near the bottom of the "Sit More, And You're More Likely To Be Disabled" NPR article:

...exercising for 30 minutes a day doesn't necessarily offset the hours of sitting.

  • These studies show correlation, not causation. Please consider rewording the opening statement. – Oddthinking Oct 12 '15 at 6:00
  • Good catch. I worded that part too strongly. – Dante Oct 12 '15 at 6:41
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OP links to: http://mashable.com/2011/05/09/sitting-down-infographic/ which refers to http://mashable.com/2011/04/22/standup-desks/ which refers to http://www.myfitnesspal.com/topics/show/215691-the-most-dangerous-thing-you-ll-do-all-day which refers to a published article: http://bmjopen.bmj.com/content/2/4/e000828.full

Abstract Objectives To determine the impact of sitting and television viewing on life expectancy in the USA.

Design Prevalence-based cause-deleted life table analysis.

Setting Summary RRs of all-cause mortality associated with sitting and television viewing were obtained from a meta-analysis of available prospective cohort studies. Prevalences of sitting and television viewing were obtained from the US National Health and Nutrition Examination Survey.

Primary outcome measure Life expectancy at birth.

Results The estimated gains in life expectancy in the US population were 2.00 years for reducing excessive sitting to <3 h/day and a gain of 1.38 years from reducing excessive television viewing to <2 h/day. The lower and upper limits from a sensitivity analysis that involved simultaneously varying the estimates of RR (using the upper and lower bounds of the 95% CI) and the prevalence of television viewing (±20%) were 1.39 and 2.69 years for sitting and 0.48 and 2.51 years for television viewing, respectively.

Conclusion Reducing sedentary behaviours such as sitting and television viewing may have the potential to increase life expectancy in the USA.

So, it MAY be dangerous. But it has not been proven in that article.

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