Two recent studies confirm the powerful role that exercise plays in controlling blood glucose levels. The first study, conducted by University of Missouri researchers and published in Medicine & Science in Sports & Exercise, found that blood glucose levels tend to spike during periods of inactivity. The second study, conducted by the Baker IDI Heart and Diabetes Institute in Australia and published in Diabetes Care, shows that office employees who take short light-exercise breaks every 20 minutes enjoy a 30 percent reduction in blood glucose levels.
Inactivity Invites Blood Sugar Spikes
In the Missouri study, the researchers evaluated the effect of inactivity on blood glucose levels among volunteers who normally exercised at the level recommended by the American Heart Association: 10,000 steps (about five miles) daily. They particularly wanted to see what effect levels of physical activity have on post-meal blood glucose spikes.
The volunteers, fitted with monitoring devices, were told to go about their normal routines for three days, taking their usual walks and doing their usual exercise. The researchers found that at the 10,000-steps-per-day level, the volunteers’ blood glucose levels did not spike after meals.
Next, the volunteers were asked to cut their daily steps to below 5,000 while continuing to eat their normal diet. The volunteers also rode rather than walked whenever possible. After the three days of relative inactivity, their after-meal blood sugar levels spiked an average 26 percent higher than the levels recorded during their more active three-day period. The researchers also found that the blood sugar spikes rose slightly higher for each day of inactivity. Once the volunteers resumed their 10,000-steps-a-day routine, their blood sugar levels quickly dropped back to what was normal for them before the experiment.
The Missouri findings show that activity levels can have a more immediate effect on blood sugar levels than even weight or diet. Even a short period of inactivity has an ill effect on blood sugar levels, and prolonged inactivity can create the conditions that invite the onset of diabetes and cardiovascular disease.
Benefits of Quick Office Breaks
The Australian study found that taking two-minute light exercise breaks every 20 minutes allowed office workers to reduce their blood sugar levels by 30 percent. The lead author, Associate Professor David Dunstan, noted that 60 percent of Australians are either overweight or obese, conditions that dramatically increase their chances of developing type 2 diabetes.
Dunstan said that companies should not only encourage employees to take short exercise breaks, but should also counsel them not to sit for longer than 30 minutes at a time. Long-term sitting can create circulatory problems as well as high blood sugar levels from inactivity.
The net effect of moving around at frequent intervals, said Dunstan, is to lower blood sugar levels-an essential part of avoiding the risk of diabetes.
Sources: New York Times, Diabetes Care