Researchers found that adults in the United States spend more than 12 hours per day sitting down, and the more time spent sitting, the greater their risk of premature death from all causes will be.
But it's not all bad news. The team also found that getting up and moving around every half an hour could help to reduce the harms of prolonged sitting.
Keith Diaz, Ph.D., of Columbia University Medical Center in New York City, NY, and colleagues recently published their findings in the Annals of Internal Medicine.
Studies are increasingly documenting the potential health risks of prolonged sitting. For example, research published last year claimed that the behavior is associated with more than 430,000 deaths across 54 countries, while a more recent study linked prolonged sitting to a greater risk of walking disability in seniors.
For this latest investigation, Dr. Diaz and team sought to learn more about the link between sedentary behavior and the risk of premature death.
More specifically, the researchers wanted to determine how bouts of sedentary behavior might influence the risk of all-cause mortality - something that they believe previous research has overlooked.
Lowest mortality risk for regular movers
The researchers analyzed the data of 7,985 black and white people, aged 45 years and above, and followed them for a median of 4 years.
The activity of each adult was assessed using a hip-mounted accelerometer, and the team used this information to calculate the how long participants spent sedentary in individual bouts, as well as the total time spent sedentary each day.
Out of a 16-hour waking day, participants spent a total of 12.3 hours sitting down, the team reports. Each single period of sedentary behavior lasted a mean of 11.4 minutes.
During the follow-up period, a total of 340 participants passed away.
The study revealed that both longer total sedentary time and longer bouts of sedentary behavior were independently associated with increased risk of all-cause mortality.
Interestingly, the researchers found that adults who kept bouts of sitting to under 30 minutes were at the lowest risk of death from all causes during follow-up.
Dr. Diaz and team say that their findings indicate that getting up and moving every 30 minutes could help to offset the health risks associated with prolonged sitting.
Based on their results, they suggest that current physical activity guidelines should be adjusted to include recommendations that target and reduce long periods of sedentary behavior.
At the moment, U.S. exercise guidelines recommend that adults engage in 75 minutes of vigorous-intensity aerobic activity or 150 minutes of moderate-intensity aerobic activity every week, as well as muscle-strengthening activities on 2 or more days per week.