Keep on Truckin… Blood Sugar Control Is Impacted With Even Just Three Days of Inactivity

August 31st, 2011 by Ryan Luce No Comments

Written by Michael O'Leary

Dr. John Thyfault

People with type 2 diabetes know they should exercise, but a new study shows stopping exercise, even for a short time, impairs blood sugar control even among healthy people who do not have type 2 diabetes.

Led by Dr. John Thyfault, an assistant professor at the University of Missouri, nutrition and exercise physiology researchers found that stopping regular physical exercise for as little as three days resulted in changes in gylcemic control linked to development of type 2 diabetes in healthy people. (Link to published site)

“This was not an exercise study, rather this was a study on the effects of inactivity,” Thyfault told Corengi by e-mail. “We transitioned moderately active individuals into a state of inactivity for a period of three days to see what metabolic changes ensued.”

The researchers studied the relationship between low levels of physical activity and glucose levels after meals, what the researchers call postprandial glucose, or PPG, which refers to the jumps in blood sugar that occur after eating. The study was published online ahead of print in the September issue of the journal Medicine & Science in Sports & Exercise.

In the study, researchers used continuous glucose monitors to measure blood sugar levels before and every 30 minutes after meals in 12 healthy, normally active 29-year-old volunteers. They recorded the glucose measurements for three days during which the participants took 10,000 steps or more per day. That’s equivalent to walking around the high-school track about 20 times, or 5 miles. They then followed that with three days of taking less than 5,000 steps per day. 

During the study participants ate the same diet and underwent a glucose tolerance test on the day after the three-day exercise period.

What they found was that after the three days that participants reduced their activity by half their glucose doubled 60 minutes after the meal.

“We now have evidence that physical activity is an important part of the daily maintenance of glucose levels,” Thyfault said. “Even in the short term, reducing daily activity and ceasing regular exercise causes acute changes in the body associated with diabetes that can occur before weight gain and the development of obesity.”

He notes that Americans on average take less than 5,000 steps per day, and the study shows that moderate exercise is important for maintaining glucose balance and reducing post-meal spikes in blood sugar in healthy individuals.

“This chronic inactivity leads to impaired glucose control and increases the risk of developing diabetes,” he said.