Don’t Take a Load Off: Too Much Sitting Is Bad for You

Office Chair

If you’ve considered getting in on the standing desk trend, you’ve probably heard the public health warnings about the dangers of too much sitting. (Would you get a standing desk? Tell us on our poll.) Several studies report an increased risk of developing cardiovascular disease with too much sitting. The good news is you can prevent it. The key may be to keep the blood moving to combat the decreased blood flow caused by sitting.

Blood vessels are lined with cells called endothelial cells. Besides keeping the blood vessels healthy, endothelial cells make sure that blood goes where it needs to by releasing molecules that either enlarge or narrow the blood vessels. They constantly feel the force of the blood flowing over them, and changes in blood flow patterns, including decreased blood flow, can reduce their effectiveness. Impaired endothelial activity increases the risk of developing diseases that affect the blood vessels such as atherosclerosis (the buildup of cholesterol, fat and other substances within and along the walls of blood vessels).

A new study discussed in this AJP-Heart podcast examined whether sitting-related diminished blood flow impaired endothelial function. To do this, the researchers compared endothelial function in the leg of their study subjects—one leg’s blood flow was reduced from sitting while the other leg’s blood flow was maintained by placing the foot in a warm water bath. After a three-hour sitting session, the researchers found that the blood vessels in the leg of the dry foot did not dilate as well as before the session, a sign of impaired endothelial function. The blood vessels in the leg on the warm water side, however, were able to dilate normally. The researchers also confirmed that leg blood flow on the dry foot side was lower after the three hours of sitting while blood flow on the warm water side remained similar.

The researchers concluded that prolonged sitting caused endothelial dysfunction because blood flow through the legs decreased. The flip side was that maintaining blood flow—in this study with a warm water bath—prevented the decline in endothelial function.

What can you do to keep your blood flowing? Jaume Padilla, PhD, the study’s lead investigator, thinks even small amounts of physical activity can help. He tries to stand as much as possible during his work day. When he’s sitting for very long periods of time, such as during long flights, he finds ways to keep his legs moving (check out these leg and other stretches from Virgin Atlantic airline that you can do while sitting). Walks are good, too. Another study from Padilla’s group also showed that a short ten minute walk could restore blood vessel health and flow in people who were sitting for six hours.

Get up and move around regularly during your day. It’s all-around good for you.

Stacy Brooks is the former director of marketing and communications for the American Physiological Society (APS). One of her favorite things about working at APS was learning about the interesting and important research that physiologists do and finding ways to communicate their science to a wide variety of audiences who benefit from these research advances.

Maggie Kuo

Maggie Kuo, PhD, is the former Communications and Social Media Coordinator for APS. Catch more of her writing in the Careers Section of Science Magazine.

Leave a Reply