Computers, not TV, are guilty of increased American sitting time, the study says
Use of leisure time increased between 4.8 and 38 percent for different age groups between 2001 and 2016, says Yin Cao, senior author of the new study and an assistant professor at surgery at Washington University School of Medicine in St. Louis.
A total of up to 43% of the US population used a computer for two or more hours a day and up to 25% used a computer for three or more hours each day in 2016.
The result of these increases: Teenagers spent about 8.2 hours a day and while adults sat for 6.4 hours a day.
Cao believes that her research, published Tuesday in JAMA, will help the Americans better understand our scaffolding habits – and change them.
Sessions during the last 1
"Research evidence has increased on the link between sedentary behavior – mainly television viewing – and a variety of diseases, including obesity, cardiovascular disease, cancer, type 2 diabetes and overall mortality, Cao says.
For the first time, the US Department of Health and Human Services mentioned last year's edition of the Physical Activity Guidelines "that people would benefit from both increased moderate and powerful activity and also reduce the time spent, "she said.
She wondered: How much does the Americans sit, and how has the trend changed over the past 15 years? To answer these questions, Cao and her co-authors used data from the National Health and Nutrition Examination Survey on 51 896 persons – 10,359 children, 9,639 teenagers and 31,898 adults – from 2001 to 2016.
Overall, up to 65% of the population reported that Don't watch TV for at least two hours every day, the study found. "This is pretty high and has been overall stable for the past 15 years," Cao said. However, the computer time has increased during the same period.
Bara 43% of children reported using a computer for an hour a day or more in 2001; that rate increased to 56% in 2016, the study indicates. The estimated prevalence of teenagers increased from 53% to 57% and for adults it went from 29% to 50% between 2003 and 2016. Only adults and teenagers reported their total sitting time.
"Hopefully, this paper will be useful in setting the national attainable goal of reducing sitting, as we already know that long seated is bad for many health outcomes, says Cao.
Every little bit helps
Peter Katzmarzyk, a professor at Louisiana State University's Pennington Biomedical Research Center and a member and colleague from the American College of Sports Medicine , said the study's value is to show trends over time.
Katzmarzyk, who was not involved in the research, noted that the paper also highlights some important differences between demographic groups that can lead to health shifts. "Seat levels were higher in men, African Americans and also in teens and adults with obesity or obesity, "he said.
Although everyone needs to focus on increasing activity and reducing sitting "it is even more important to limit the time spent by people who do not fulfills the guidelines for physical activity, because they are at highest risk "for chronic diseases and premature mortality, he said.
A separate study published this week in the Journal of the American College of Cardiology found that moderate-to-severe physical activity compensates for the link between sitting time and increased risk of death from all causes and the risk of cardiovascular disease. The study tracked nearly 150,000 people aged 45 and older.
Keith Diaz, Assistant Professor of Behavioral Medicine at Columbia University Department of Medicine, said the announcement of the research published in JAMA may be known but important.
"We become very sedentary as a nation, and one of the main contributors to that rise of sedentary time is our computer use," says Diaz, who did not participate in the research.
"What I really suffered from was 62% of the children watching TV for two or more hours a day," he said. "And they also use computers a lot."
A parent, he added, "these behaviors are really obviously in childhood , and it is probably something we must start fighting and target really early if we are to break this evil cycle of us being a more sedentary society. "
He said people who have read their research often ask him two questions : "What should I do when I take a break from my sitting time?" and "When I take that break, how long will that break be?"
His latest study showed that intensity is important but not necessary.
"So if you were to replace 30 minutes of sedentary time with 30 minutes of light activity – a relaxed walk down the hall – you would lower your risk of early death by 17%," he said. Replace 30 minutes with more powerful activity, reducing your risk by 35%.
He also found that "short outbreaks of activity, if you get enough of them over the day, will suffice to lower your risk of sitting all day."
"To fight sitting you do not have to go to the gym and train for hours at a time," he said.
Getting off your office chair or couch and taking a short break here or there is enough, he said, "It doesn't have to be complicated. It doesn't have to be difficult. It doesn't have to be long."