A review article published last year in the journal Exercise and Sport Sciences Reviews discussed the medical hazards of prolonged sitting. The authors point out that changes in transportation, building standards, communications, entertainment technology, and workplace practices, have combined to significantly reduce demands for physical activity.
They propose, with supporting epidemiological evidence, that prolonged sitting is a distinct health risk factor from too little exercise and, furthermore, that breaking up sedentary time can provide health benefits.
Even adults who meet the recommended exercise guidelines of thirty minutes per day may be sedentary for prolonged periods during the day. An example would be someone who exercises vigorously every morning before going to work in an environment that requires sitting for hours at a time. According to the authors, such “Active Couch Potatoes” showed significant detrimental effects on their waist circumference (an indicator of % body fat), blood pressure, plasma glucose levels, triglycerides and HDL cholesterol.