Humans are not designed to spend the entire day seated. Nonetheless, billions of us do it at least five days per week, as Western work patterns dictate.
The health consequences of remaining on our bums all day are significant. According to studies, those who sit for extended durations are more likely to develop chronic diseases such as cancer, heart disease, and diabetes. Even daily bursts of exercise are not necessarily a cure for lengthy periods of desk work, despite their value.
The UK’s National Health Service (NHS) acknowledges that there is insufficient data to establish a daily restriction on the amount of time people should spend sitting.
Fortunately, academics at Columbia University in the United States are attempting to fill this gap in the research. They intended to find out how to limit the hazards of sitting all day without having to do anything extreme like quit your work.
The resulting study, led by Keith Diaz, associate professor of behavioral medicine, was admittedly modest in size. Only 11 adults participated. Still, it offers a launching pad for further research.
What’s the bare minimum that we have to walk to offset health effects?
Over the course of five days, each participant was asked to sit in a lab for eight hours, mimicking a regular workday. On one of those days, participants sat all day, only getting up to use the restroom. Diaz and his crew tested a variety of various walking tactics on the others to break up the sitting.
“Our goal was to find the least amount of walking one could do to offset the harmful health effects of sitting,” Diaz wrote for The Conversation in a blog post. “In particular, we measured changes in blood sugar levels and blood pressure, two important risk factors for heart disease.”
According to their results, the only method that effectively reduced blood sugar levels was a five-minute light walk every half-hour, which reduced the blood sugar surge after eating by over 60 percent when compared to sitting down.
During the study, researchers also used a questionnaire to ask participants to score their mental health.
“We found that compared with sitting all day, a five-minute light walk every half-hour reduced feelings of fatigue, put participants in a better mood, and helped them feel more energized,” he wrote. “We also found that even walks just once every hour were enough to boost mood and reduce feelings of fatigue.”
Short and frequent or long and infrequent?
More research is needed, but the results agree with advice from the UK government’s Health and Safety Executive, which suggests “short breaks often, rather than longer ones less often”. It recommends five to ten minutes every hour.
Diaz and his colleagues are currently studying additional ways for mitigating the health risks of extended sitting, particularly for people who can’t just get out of their seats, such as cab drivers.
“Finding alternative strategies that yield comparable results can provide the public with several different options, and ultimately allow people to pick the strategy that works best for them and their lifestyle,” said Diaz.
Source study: Medicine & Science in Sports & Exercise— Breaking up prolonged sitting to improve cardio metabolic risk: Dose-response analysis of a randomized cross-over trial