This document discusses the negative health effects of prolonged sitting at work. It notes that on average, workers sit for about 21 hours per day at their desks. Prolonged sitting shuts down leg muscle activity and lowers calorie burning and fat breakdown. It can decrease good cholesterol, squeeze blood vessels, cause insulin insensitivity, and increase stress levels over time. The document provides tips for sitting properly at 135 degrees and increasing activity during the work day, such as walking, taking the stairs, visiting the gym, and parking further away.