'Evidence shows that inactivity or lack of movement that is best exemplified by prolonged sitting, actively promotes dozens of chronic diseases, and these risks apply even if you're very fit. In fact, sitting for too long, too often, is an independent risk factor for ill health and reduced longevity.
Dr. James Levine is co-director of the Mayo Clinic and the Arizona State University Obesity Initiative and author of the book "Get Up! Why Your Chair Is Killing You and What You Can Do About It."
According to Levine, there are at least 10,000 published studies showing that sitting harms health, irrespective of other lifestyle habits, including an excellent exercise program.'