Allentown Morning Call, MCT
Those negative health effects can be summarized as a kind of "metabolic syndrome," in which certain cellular enzymes that metabolize fats and sugars become inactive when we sit for 60 to 90 minutes. The result: "lack of movement and low enzyme activity contribute to weight gain, diabetes and a reduction in HDL- the good cholesterol."
Studies show impact of prolonged sitting
In a recent New York Times blog post called "Meet the Active Couch Potato," Gretchen Reynolds highlights two studies that focused on this phenomenon. In one, researchers in Australia analyzed "medical records and lifestyle questionnaires of 220,000 Australian adults 45 and over." The study found that "the more hours the men and women sat every day, the greater their chance of dying prematurely" - even if the study participants exercised.
Another study in Finland used special electromyography equipment to measure the muscle activity of volunteers. They found that overall muscle activity, and sitting time, remained relatively unchanged even when participants exercised. Reynolds writes:
Surprisingly, how much people exercised or what kind of exercise they chose did not change sitting time. Whether volunteers worked out for less than an hour or for more than 90 minutes, they spent an equivalent amount of time the rest of the day being mostly torpid physically.According to Dr. Taija Juutinen Finni, who spearheaded the research, the results "suggest that normal exercise, which fills so few hours of even active people’s days, may not be enough in terms of health."
I'm definitely an active couch potato. I used to sit in an uncomfortable office chair for up to 12 hours a day, taking rare breaks, and heading to the gym directly after work. I suffered from significant back pain that was alleviated only by taking prescription pain meds. Interestingly, my doctors never suggested that my back pain could be related to my office environment. But when I started a family and took extended maternity leave, it was clear that prolonged sitting at my computer was intricately related to my problems, as my back pain disappeared altogether (along with my gym attendance).
I'm now back at a computer and desk, and I try to exercise 30 minutes most days. While the number of sitting hours have decreased significantly compared to my original job, I still sit for large blocks of time. Of course, my back pain has returned (though thankfully not with as much severity).
To begin breaking free of "active couch potato" status, sit in a more ergonomically correct manner. If you can't afford an ergonomic office chair, consider sitting on an exercise ball. I've found that it has helped me a great deal. (Of course, check with your doctor first.) Also, get up and move as often as possible. Standing, walking, or even moderate leg exercises at least once an hour is advised. Getting a more active job might not always be possible, but it could help.
We also need to consider the impact that sitting has on our kids, who sit for long periods of time at school and often at home. Remember, it's not enough anymore to think of prolong sitting as being back on your back, neck and shoulders. Important metabolic activities and general health is at stake, too.
For more information:
"PhysEd: The Men Who Stare at Screens" by Gretchen Reynolds, New York Times blog post