The fact that anti-fatigue matting and footwear is a well established thing, and the health and safety staff have videos about the risks of standing all day was a pretty big clue that standing all day is not a great idea.
Also, lying down all day is not good for you either.<p>To summarize: spending the entire day in one position is bad for you. Human beings are animals. Animals are meant to move about.
If only we had some way know knowing when we should sit, stand, or lay down. We need millions in government-provided funding to figure this out for us.