Sedentarianism Increases Risk Of Mortality

It may be easy to ignore sedentarianism to avoid the P.C. police, but make no mistake about it this is unhealthy, it is not normal, and it contributes to a variety of chronic diseases plaguing the struggling healthcare system. A sedentary lifestyle should be viewed as a marker of metabolic dysfunction that is chronic, easily reversible, and solvable at little to monetary burden. Unless a person is recovering from an injury or sickness, or has a disability, being sedentary is a choice that equals having a disease leading to early death. 

Sedentarianism is a dangerous health risk because it reduces muscle contractions, blood flow, and glucose metabolism among other things. Studies show that people who get up and move around after sitting for twenty minutes live longer. Now a new study published in the Journal of the American Heart Association shows that older women who sat for 11+ hours a day increased their risk of death by 30% regardless of whether they exercised vigorously.

"When you're sitting, the blood flow throughout your body slows down, decreasing glucose uptake. Your muscles aren't contracting as much, so anything that requires oxygen consumption to move the muscles diminishes, and your pulse rate is low," said Andrea LaCroix, Ph.D., M.P.H., Distinguished Professor at the Herbert Wertheim School of Public Health.

This study examined measurements of sitting and daily activity that were collected from wearable devices worn on the hips of 6,489 women between the ages of 63 to 99 years old for seven days, and the women were followed for 8 years for mortality outcomes. The data is part of an ongoing long-term national project called the Women’s Health Initiative (WHI) started in 1991. 

 "Sedentary behavior is defined as any waking behavior involving sitting or reclining with low energy expenditure," explains study co-author Steve Nguyen, Ph.D., M.P.H., a postdoctoral fellow at the University of California San Diego Herbert Wertheim School of Public Health and Human Longevity Science. "Previous techniques for calculating sedentary behavior used cut points that identified low or absent movement. The CHAP algorithm was developed using machine-learning, a type of artificial intelligence, that enhanced its ability to accurately distinguish between standing and sitting."

According to the results of this study, exercise is not able to undo the negative effects of living a sedentary lifestyle; finding that whether the participants engaged in low or high amounts of moderate to vigorous intensity physical activity they showed the same heightened risk of mortality if they sat for long uninterrupted hours. 

"If I take a brisk long walk for an hour but sit the rest of the day, I'm still accruing all the negative effects on my metabolism," said LaCroix. "The risk starts climbing when you're sitting about 11 hours per day, combined with the longer you sit in a single session. For example, sitting more than 30 minutes at a time is associated with higher risk than sitting only 10 minutes at a time. Most people aren't going to get up six times an hour, but maybe people could get up once an hour, or every 20 minutes or so. They don't have to go anywhere, they can just stand for a little while."

"Looking beyond conditions like cardiovascular disease, we start thinking about cognitive outcomes, including dementia," said Nguyen. "There are cognitively stimulating activities that can result in sedentary behavior, like sitting while studying a new language. Is sedentary behavior in that context overall bad for a person? I think it's hard to say." 

"We've created this world in which it's so fascinating to sit and do things. You can be engrossed by TV or scroll on your Instagram for hours. But sitting all the time isn't the way we were meant to be as humans, and we could reverse all of that culturally just by not being so attracted to all the things that we do while sitting,” said LaCroix.