It is no secret that a sedentary lifestyle is linked to poor
health. Our bodies are designed for movement, and when they are deprived of
movement an array of negative health outcomes may result. For many of us, our
jobs require extended hours of sitting. In order to counteract the seat time
associated with work many people invest in a gym membership or make physical
exercise a part of their normal routine. While this certainly makes us feel
better, are we really combating the detrimental effects of so many hours of
seat time? A recent study examined all of the data on this topic, and you may
be surprised what they found.
The study in question examined the data from 16 previous
studies examining the link between sedentary behavior and increased risk of
chronic conditions and mortality. In short, all of these studies were
attempting to determine if a sedentary lifestyle significantly increases your
chances of being chronically sick or dying, and if routine exercise combats
these effects. We've included a link to the original study here if you want to check it out for yourself.
In a nutshell, the data found that those with a sedentary
lifestyle (sitting for 8+ hours per day) and low physical activity had a 12-59%
higher mortality rate. The group with the highest level of physical activity
(60-75 minutes per day) experienced no increased mortality as a result of a
sitting for 8+ hours per day. Even sitting for just four hours per day was
associated with an increased risk of dying when physical activity is low.
These findings are not that surprising, but here is where
things get interesting. The study also included data on time spent watching TV
while sitting. When including TV time in the equation, the results changed
significantly.
For individuals who watch TV for three or more hours per day,
there was an increased risk of death in every population EXCEPT the group with
the highest level of physical activity. In this group, the research also found
that even with frequent exercise, watching 5+ hours of TV per day significantly
increased the mortality rate.
Summary:
Physical activity for 60-75 minutes per day can
significantly reduce your increased risk of death/disease associated with
sitting time. Here’s the catch: high TV time (3+ hours per day) changes the
equation. In the case of high TV time, the beneficial effects of exercising to
counteract sitting are eliminated. Even in the most physically active group,
exercise did not eliminate the increased risk with 5+ hours of TV time per day.
Takeaway:
If you have a job or lifestyle that includes a lot of
sitting, research shows that moderate intensity exercise for about one hour per
day can counteract the negative effects. However, if you watch a lot of TV,
your hard work in the gym may not be decreasing your risk of death associated
with all of the sitting. We can all find time in our busy schedule to decrease
TV time and increase exercise time. If we don’t find time to be healthy now, we
will have to find time later to be sick.