I always wondered why I hated sitting…
New research in the diverse fields of epidemiology, molecular biology, biomechanics, and physiology is converging toward a startling conclusion: Sitting is a public-health risk. And exercising doesn’t offset it. “People need to understand that the qualitative mechanisms of sitting are completely different from walking or exercising,” says University of Missouri microbiologist Marc Hamilton. “Sitting too much is not the same as exercising too little. They do completely different things to the body.”
In a 2005 article in Science magazine, James A. Levine, an obesity specialist at the Mayo Clinic, pinpointed why, despite similar diets, some people are fat and others aren’t. “We found that people with obesity have a natural predisposition to be attracted to the chair, and that’s true even after obese people lose weight,” he says. “What fascinates me is that humans evolved over 1.5 million years entirely on the ability to walk and move. And literally 150 years ago, 90% of human endeavor was still agricultural. In a tiny speck of time we’ve become chair-sentenced,” Levine says.
Hamilton, like many sitting researchers, doesn’t own an office chair. “If you’re standing around and puttering, you recruit specialized muscles designed for postural support that never tire,” he says. “They’re unique in that the nervous system recruits them for low-intensity activity and they’re very rich in enzymes.” One enzyme, lipoprotein lipase, grabs fat and cholesterol from the blood, burning the fat into energy while shifting the cholesterol from LDL (the bad kind) to HDL (the healthy kind). When you sit, the muscles are relaxed, and enzyme activity drops by 90% to 95%, leaving fat to camp out in the bloodstream. Within a couple hours of sitting, healthy cholesterol plummets by 20%.
Time to start standing at work? Yep, doing it now in fact!
Tags: Health, bloodstar by bloodstar
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