The average American is now sitting or otherwise inactive for over eight waking hours per day — a figure which only rises with age — and no age group above 30 is committing more than 30 minutes to moderate or vigorous activity per day. All adults should aim for at least 150 minutes of physical activity per week — a broadly supported guideline that has been endorsed by the World Health Organization (WHO). However, the new BMJ papers suggest that even that modest goal might be too high for some people and the priority should be to avoid inactivity as much as possible.
The WHO identifies physical inactivity as "the fourth leading risk factor for global mortality" and estimates that it's caused 3.2 million deaths globally.
