One Hour Physical Activity Offsets 8 Hours Sitting on Your “Bum”

Sitting on your ass all day bad for health.

  • One hour of brisk walking or cycling for pleasure may eliminate the harmful effect of sitting
  • Physical inactivity costs the global economy over US$67.5 billion per year in health care costs and lost productivity

A new study of over 1 million people finds that doing at least one hour of physical activity per day, such as brisk walking or cycling for pleasure, may eliminate the increased risk of death associated with sitting for 8h a day.

Physical inactivity is linked to an increased risk of heart disease, diabetes and some cancers and is associated with more than 5 million deaths per year and, as the first global economic analysis of physical inactivity shows, costs the world economy over US$67.5 billion per year in health care costs and lost productivity.

The findings come from a new four-paper Series published in The Lancet and launched in London prior to this years’s Summer Olympic Games. The authors of the Series warn there has been too little progress in tackling the global pandemic of physical inactivity since the 2012 Olympics, with a quarter of adults worldwide still failing to meet current recommendations on physical activity.

Researchers analysed data from over 1 million people from 16 studies. The research team wanted to see how many hours of daily physical activity would be required to eliminate the association between prolonged sitting time and increased risk of death. People who sat for 8 hours a day but were physically active had a much lower risk of death compared to people who sat for fewer hours a day, but were not physically active. This suggests that physical activity is particularly important, no matter how many hours a day are spent sitting. In fact, the increased risk of death associated with sitting for 8 hours a day was eliminated for people who did a minimum of 1 hour physical activity per day.

“There has been a lot of concern about the health risks associated with today’s more sedentary lifestyles,” says lead author Professor Ulf Ekelund, the Norwegian School of Sports Sciences, Norway and the University of Cambridge, UK “Our message is a positive one: it is possible to reduce – or even eliminate – these risks if we are active enough, even without having to take up sports or go to the gym.”

He adds: “For many people who commute to work and have office-based jobs, there is no way to escape sitting for prolonged periods of time. For these people in particular, we cannot stress enough the importance of getting exercise, whether it’s getting out for a walk at lunchtime, going for a run in the morning or cycling to work. An hour of physical activity per day is the ideal, but if this is unmanageable, then at least doing some exercise each day can help reduce the risk.”

The research team also looked at time spent watching TV per day – a specific type of sedentary behaviour – in a subgroup of approximately half a million people. They found similar results: sitting watching TV for over 3h per day was associated with an increased risk of death in all activity groups, except the most active.