Humans are built to move. Our bodies are designed to be mobile and our physiological systems work best when we are. Of course, the jobs we most often have and the lifestyles we most often live don’t promote the movement our bodies need. According to the American Heart Association, we should be moving with moderate intensity for at least 150 minutes every week. The Centers for Disease Control and Prevention reports, however, that only 23% of Americans are getting that amount of exercise.

We’re hearing more and more from health professionals about just how bad prolonged immobility, especially sitting, is for us. Britain’s National Health Service explains that evidence on the subject goes back to the 1950s, “when researchers found double decker bus drivers were twice as likely to have heart attacks as their bus conductor colleagues. The drivers sat for 90 per cent of their shifts, the conductors climbed about 600 stairs each working day.”

A 2018 study from the American Journal of Epidemiology found the links between a sedentary lifestyle and early mortality to be much more comprehensive. It explains that “prolonged leisure-time sitting” is “associated with higher risk of mortality from all causes.” If you’re the kind of person who finds fear to be a good motivator, let’s delve into how our sedentary ways put us at risk for some major health concerns.

Without regular muscle contractions in your leg muscles to help blood flow back to your heart, your circulatory system is compromised, meaning blood can pool in your legs. This pooled blood puts stress on your leg veins, which can extend them and create varicose veins.

Many people don’t like the look of varicose veins on their legs, but they’re not usually a health concern. More troubling is the risk of developing deep vein thrombosis, which is a blood clot that forms in a leg vein as a result of blood not circulating properly. Blood clots, of course, are a serious issue that can become a medical emergency if they move to the heart or lungs.

Muscle weakening can result from sitting for long periods, especially, as you might expect, in your back, legs, hip flexors and gluteal muscles. Weakened muscles in general can pose risks, especially for an aging population, because they increase the chance of strains, injuries and falls.

People who sit for long periods every day frequently report back and joint issues, especially when sitting is coupled with the bad posture so many of us have. In Start Standing, Dr. R.J. Burr writes that “tension and imbalance in your back and neck” caused by poor seated postures can “start a cascade of events” that can lead to serious spinal issues.

Physician Edward R. Laskowski tells the Mayo Clinic that studies have linked prolonged sitting with “a cluster of conditions — increased blood pressure, high blood sugar, excess body fat around the waist and abnormal cholesterol levels — that make up metabolic syndrome.” This “cluster” raises the risks of developing type 2 diabetes and cardiovascular disease.

Laskowski points to research that suggests that “those who sat for more than eight hours a day with no physical activity had a risk of dying similar to the risks of dying posed by obesity and smoking.” While he notes that more studies are needed to assess the effects of sitting, it’s clear that inactivity is a significant risk factor for the major health challenges of our day.

Sitting has been linked to increased risk of lung, uterine and colon cancers, although more studies are needed to determine why this link exists. Scientific American’s Agata Blaszczak-Boxe reports that the risk of colon and endometrial cancers increases with the number of hours a person spends sitting every day. She notes that the research also suggests that the risk of cancer increases independently of how active people are when they’re not sitting.

Inactivity affects our mental and emotional well-being just as much as our physical well-being. The Association for Psychological Science reports that a 2013 study found “a significant relationship between rates of psychological distress and sitting.” The study also found “increased prevalence of moderate symptoms of anxiety and depression” in subjects who sat for more than 6 hours per day.

While the effects of immobility on mental health are only just being discussed, preliminary research findings make a lot of sense. When we move, our bodies pump blood (and therefore fresh oxygen) to the brain, which help it to function. Exercise releases endorphins and other neurochemicals that regulate mood and sleep. In fact, Kirstin Weir of the American Psychological Association reports that a 2007 study found exercise to be “generally comparable to antidepressants for patients with major depressive disorder.”

Without that movement, our neurochemistry doesn't function as well. In addition, chronic low-level pain, stiffness or discomfort, which is so often a result of being stuck in the same position for hours every day, impact our mood and our ability to focus.

Linda Wasmer Andrews of Psychology Today explains that the link between inactivity and depression “may be a two-way street” or a vicious cycle, where inactivity makes a person more depressed, which makes them less likely to be active, and so on. She argues that the negative mental health effects we’re just starting to understand “may also be rooted in what people tend to do while in their chairs:” passive TV watching instead of engaging with friends or family or getting out into nature can make a person feel more isolated, lonely and depressed.

That’s a lot of alarming news. The silver lining is that countering these risks is as simple as getting up and moving. Not all of us have an active profession like a server or a tree surgeon or a double-decker bus conductor, so it's extra important for us to find ways to keep moving. It’s recommended that people get up and walk for a few minutes every half hour and incorporate low-level activity throughout the day. 

So now that you’ve sat through this whole article on the health effects of sitting, doesn’t a walk sound lovely?

feature image: Paula Schmidt; image 1: Burst