According to a study in the British Journal of Sports Medicine as little as 11 minutes of exercise can offset the negative effects of sitting on your posterior all day.
The study, a meta-analysis of nine other studies tracking nearly 45,000 people, found that those who were most sedentary risked dying prematurely. But even when people sat as much as 8.5 hours a day, getting just 11 minutes of moderate exercise significantly cut that risk. Thirty to 40 minutes of exercise was even more helpful.
“It doesn’t matter if you accrue it in 30 minutes or one-minute bouts over 30 occasions,” says Keith Diaz, an assistant professor of behavioral medicine at Columbia University and one of the coauthors of the study. “The guidelines historically used to recommend that it had to be 10 minutes or more time, and we found that that’s just not the case. Any movement, no matter what duration, is beneficial, as long as you accrue enough of it.”
Just so you know, sitting too much is bad for you.
The above definition may seem rather intuitive, but this is not the way that the term sedentary has been used by exercise science researchers for the past 50 years. Up until very recently, referring to someone as sedentary meant simply that they were not meeting current guidelines for physical activity. In simple terms, if you were exercising for 60+ minutes/day, you were considered physically active. If you were exercising 10 minutes/day, you were sedentary. Case closed. But as we will discuss below, sedentary time is closely associated with health risk regardless of how much physical activity you perform on a daily basis. Further, it is entirely possible to meet current physical activity guidelines while still being incredibly sedentary. Thus, to quote researcher Marc Hamilton, sitting too much is not the same as exercising too little. (if you take only one thing from this post, let it be that quote from Dr Hamilton). Which is why it is so important that when we use the term "sedentary", we are all on the same page about what that means…
But what is fascinating is that the relationship between sitting time and mortality was independent of physical activity levels. In fact, individuals who sat the most were roughly 50% more likely to die during the follow-up period than individuals who sat the least, even after controlling for age, smoking, and physical activity levels. Further analyses suggested that the relationship between sitting time and mortality was also independent of body weight. This suggests that all things being equal (body weight, physical activity levels, smoking, alcohol intake, age, and sex) the person who sits more is at a higher risk of death than the person who sits less.