Exercise Science

Too Much Sitting Is Killing Us (ANH-USA)

FROM: Alliance for Natural Health-USA Jan. 3 2012

Studies say that even moderate to vigorous exercise doesn’t counteract the damage.

A study published in the American Heart Association’s journal Circulation showed
that each extra hour of television watching (the ultimate sitting
sedentary activity) per day was associated with an 18% increase in
deaths from heart disease and an 11% increase in overall mortality.
People who watched TV for at least four hours a day were 80% more likely
to die of cardiovascular disease than those who watched two hours or
less, and 46% more likely to die of any cause.

have smart readers, and many of you will immediately ask: “Weren’t
there other factors, not just sitting, that resulted in this outcome?”
Yet that doesn’t seem to be the case. There are specific reasons why
sitting, in itself, appears to be dangerous. The message seems to be to move around. But
if you aren’t moving around, stand or lie down, which humans have done
throughout their history. Avoid sitting in a chair, an activity that is
relatively new for human beings and not at all good for us.

Surprising as it is, the increase in heart and mortality risk observed in the Circulation
study affected people who met exercise guidelines—and were independent
of eating habits as well! Studies reported significant associations
between total sedentary time with blood glucose, blood lipids, and
adiposity, even in people who performed moderate to vigorous exercise
several times each week.

studies also show that how much time we are sedentary is related to how
well our bodies process fats. The studies in rats show that leg muscles
only produce the lipase lipoprotein (fat-processing) molecule when they
are being actively flexed—that is, when standing or, better still,
walking around—and low levels of the molecule are associated with health
problems, including heart disease. In short, sitting makes this
important molecule slow down. In fact, actively contracting the muscles
produces a whole suite of substances that have a beneficial effect on how the body uses and stores sugars and fats.

people, on a daily basis, simply shift from one chair to another—from
the seat in the car to the chair in the office to the chair in front of
the television,” said to the lead author of the study.
“Even if someone has a healthy body weight, sitting for long periods
still has an unhealthy influence on blood sugar and blood fats.”

should be noted that sitting too much is not the same as exercising too
little. They do completely different things to the body. Standing recruits specialized muscles designed for low-intensity activity—muscles
that are very rich in enzymes. The lipoprotein lipase enzyme  grabs fat
and cholesterol from the blood, burning the fat into energy while
shifting the cholesterol from LDL (the bad kind) to HDL (the healthy
kind). When you sit, the muscles are relaxed, and enzyme activity drops
by 90% to 95%, leaving fat to camp out in the bloodstream. Within a
couple hours of sitting, healthy cholesterol plummets by 20%.

A Canadian study reached a similar conclusion.
After adjusting for potential compounding factors (smoking, exercise
levels, etc.), the study found that the longer people sat, the higher
the risk of mortality from all causes except cancer.

The good news is that inserting breaks into your sedentary periods can help.
Periodically taking time out from your computer, desk, television, and
driving time to walk, move around, stretch, and flex your muscles, is
good for you. These spurts of activity are associated with a smaller
waist circumference, lower body mass index, and lower blood lipid
levels, and better glucose metabolism.

stand up desk might be a good idea as well. Don’t have room for one?
Too expensive? Then pile some books or something else on top of your
existing desk and put your laptop where you can type standing up when
you want to, either often or as a break.

ANH-USA, we believe that true health comes from a combination of diet
(and supplements), exercise, and lifestyle. Politically, so much is
happening regarding supplements and diet that we spend most of our
newsletter space focusing on those areas. But science tells us that our
lifestyle choices—simple decisions made daily—can make a huge impact on
our health, for good or for ill.

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