Sitting for hours at a desk can play havoc with our metabolic health, contributing over time to high blood sugar and high cholesterol, even in people who otherwise seem mostly healthy.
But a practical though small new study shows that standing up and moving every 30 minutes for about three minutes may lessen the health impacts of over-sitting. The study found that climbing several flights of stairs, bopping through some jumping jacks or squats, or even taking as few as 15 steps during these mini-breaks improved aspects of blood sugar control among office workers, without noticeably interrupting their work flow.
But the study, which involved 16 middle-aged, white-collar workers at high risk for Type 2 diabetes, also indicates that these bi-hourly, three-minute breaks likely represent the minimum amount of movement needed to protect metabolic health. While 15 steps twice an hour may be a good start, they should not be the only steps we take towards reducing how much we sit.
Every waking hour spent in sedentary postures – that is, sitting or lying – increases risk for metabolic syndrome and Type 2 diabetes
For most of us, sitting is not just commonplace but constant. According to epidemiological studies, adults in the United States typically sit for about six-and-a-half hours a day, with most of that time uninterrupted by standing or strolling. This postural lassitude likely accelerated during the pandemic. Preliminary data suggests that many of us are more inactive now than in 2019, especially if we have children and jobs.
Such relentless sitting squashes metabolic health. Or, as the new study’s authors write, “Every waking hour spent in sedentary postures – that is, sitting or lying – increases risk for metabolic syndrome and Type 2 diabetes.” Blame flaccid muscles. When we sit, the muscles in our legs, which are the largest in our body and are usually active and hungry, barely contract, so, require minimal fuel and slurp little sugar from our bloodstreams. They also do not release biochemical substances that would normally help break down fatty acids in the blood. So, when we hunch over our desks, blood sugar and cholesterol build up in our bloodstreams.
Helpfully, frequent breaks from sitting improve blood sugar control and cholesterol levels, past studies show. But much of that research took place in university labs and lasted only a day or two, conditions that do not reflect real life.
So, for the new study, which was published last month in The American Journal of Physiology: Endocrinology and Metabolism, an international consortium of scientists, led by researchers at the Karolinska Institute in Stockholm, Sweden, decided to see what would happen if office workers agreed to break up their sitting time, over three weeks, in their normal workplace.
They began by recruiting 16 middle-aged men and women in Stockholm with sedentary desk jobs and a history of obesity, putting them at high risk for metabolic problems such as diabetes. They checked the volunteers’ current metabolic health and asked them to wear activity monitors for a week, to get baseline numbers.