Having a sedentary lifestyle and skipping the gym are both habits that can result in health problems from muscle atrophy to cardiovascular issues and weight gain. It’s been said that “sitting is the new smoking” and it’s accurate. Many jobs require that employees work at a desk or in one limited area and there are not always opportunities to get up and move around.
It’s not only workplaces either. There’s a link between sitting for long periods “binge-watching” movies or television shows and dangerous blood clots. While the impact on general health is well known, research from UCLA shows that it’s not just diabetes, heart attack or strokes that can result from too much sitting. There are also risks to the brain and the ability to form new memories. It’s been a tough sell for health experts to get people to understand the risks to their cardiovascular fitness but researchers are hoping that further information that shows how the brain is affected by too much sitting might be better received.
The study focused on people aged 45 to 75. Participants filled out surveys on physical activity levels, hours spent sitting and any sports or exercise programs they were involved with. High-resolution MRI scans were also part of the work. These scans can image the brain with incredible detail, specifically the medial temporal lobe (MTL). It’s this part of the brain that works primarily on forming new memories, such as learning a new skill or memorizing needed information. Episodic memory, remembering significant events from the past, is also processed in the MTL and it’s the kind of memory loss that is found in patients with Alzheimer’s.
So what were the scientists at UCLA hoping to establish? In the MTL thinning of brain tissue is often a precursor to some forms of dementia. Thinning of cortical tissue is expected, to a certain degree, with normal aging, but the team at UCLA found that even among participants who reported high levels of physical activity if they also spent long periods of sitting, they still had increased thinning of the MTL. While exercise can mitigate cardiovascular issues, weight gain, and heart disease, in the UCLA study, it wasn’t enough to offset brain changes.
As with any research, there were some limits to the study. There was not enough information found to say that a sedentary job, with extended periods of sitting, caused the changes seen in the brain. It was an association between thinner cortical tissue and more extended hours spent sitting that was troubling to the researchers. There was also no data on whether or not participants took breaks to stand and walk around during their jobs. While previous research studies have found that people who work out often have more brain volume than those that don’t, the finding that adequate levels of physical activity did not prevent the thinning seen in the patients who spent hours a day sitting down that was a surprise.
Lead author of the study Prabha Siddarth, Ph.D. is a Biostatistician at UCLA and a lead author of the work. In an interview with the L. A. Times, she explained, “Of course, we need larger samples and better ways to measure patterns of sedentary behavior. But if you're sitting for long periods of time, it seems that that factor — not physical activity — becomes the more harmful or more significant measure of your fitness. Even for people who are physically active, sitting a lot seems to be bad for your brain."
The team hopes to continue the research by following a group of people over multiple years and gathering more specific information such as gender, race, and weight. The video below has more information, but stand up and watch it, you’ll remember it better.
Sources: UCLA via Science Daily, Los Angeles Times, PLOS One