Frequent Breaks from Sitting May Improve Daily Blood Sugar Fluctuations

Study explored short exercise “snacks” in volunteers’ daily lives

Rockville, Md. (August 10, 2021)—Frequent activity breaks from sitting may improve fasting blood sugar (glucose) levels and stabilize daily fluctuations, according to new research. The study, the first of its length to explore the effects of activity breaks in “free-living” conditions, is published ahead of print in the American Journal of Physiology-Endocrinology and Metabolism. It was chosen as an APSselect article for August.

“Every waking hour spent in sedentary postures (i.e., sitting or lying) increases risk for metabolic syndrome and type 2 diabetes.”

Life in the 21st century has made people more sedentary than those who lived in earlier times. Previous research estimates that people in Europe spend about 40% of their leisure time watching television. “Every waking hour spent in sedentary postures (i.e., sitting or lying) increases risk for metabolic syndrome and type 2 diabetes,” according to the authors of the new study. Many people do not meet current physical activity guidelines, “hence, breaking sedentary behavior may offer a pragmatic, easy way to interpret public health intervention for improved insulin sensitivity and metabolic wellbeing,” the researchers added.

In the new study, over a three-week period, the research team followed adults with obesity who reported having a sedentary lifestyle and/or job. For 10 hours each day, the volunteers wore fitness tracking devices that reminded them every 30 minutes to get up and move. At each notification, the participants performed three minutes of low-to-moderate intensity activity, such as walking or climbing stairs. The active group was compared to an age- and body mass index-matched control group that did not perform frequent activity breaks in their daily lives.

The research team found that the active group had lower LDL “bad” cholesterol and fasting glucose levels than the control group. The active volunteers also had less variability in their daily blood sugar levels—fewer spikes and dips that may have resulted from better blood flow—than the controls. However, the frequent activity breaks did not improve overall glucose tolerance or fat content in the muscles. The minimal activity requirements—at least 15 steps every 30 minutes—may not be enough to realize significant improvements in glucose tolerance. “Our intervention may represent the minimum effective dose for breaking sedentary behavior, with large volumes of total activity required to elicit greater health benefits,” the researchers wrote.

The free-living portion of the study is an important distinction, as it represents physical activity people routinely perform in their daily lives rather than for a short period of time in a lab. “To our knowledge, this is the longest duration study to investigate the impact of [frequent activity breaks from sitting] and, as such, our findings have important translational implications,” the researchers explained.

Read the full article, “Three weeks of interrupting sitting lowers fasting glucose and glycemic variability, but not glucose tolerance, in free-living women and men with obesity,” published ahead of print in the American Journal of Physiology-Endocrinology and Metabolism. It is highlighted as one of this month’s “best of the best” as part of the American Physiological Society’s APSselect program. Read all of this month’s selected research articles.

NOTE TO JOURNALISTS: To schedule an interview with a member of the research team, please contact the APS Communications Office or call 301.634.7314. Find more research highlights in our Newsroom.

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