If you’re reading this article sitting down—the position we all hold more than any other, for an average of 8.9 hours a day—stop and take stock of how your body feels. Is there an ache in your lower back? A light numbness in your rear and lower thigh? Are you feeling a little down?
These symptoms are all normal, and they’re not good. They may well be caused by doing precisely what you’re doing—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.