Short Walks Protect Against Diabetes

With an estimated 79 million Americans have pre-diabetes but showing no signs, health experts explore inexpensive preventive strategies that may help to prevent the development of type-2 diabetes.  High post-meal blood sugar is a strong determinant of excessive 24-hour glucose levels, and research suggests that people who eat a big afternoon or evening meal and often then are sedentary for the remainder of the day, are at-risk for rapid blood sugar spikes that can potentially cause damage.  Loretta DiPietro, from George Washington University School of Public Health & Health Services (Washington DC, USA), and colleagues enrolled ten men and women, ages 60 years and older, who were otherwise healthy but at risk of developing type 2 diabetes due to higher-than-normal levels of fasting blood sugar and to insufficient levels of physical activity. Subjects completed three randomly-ordered exercise protocols spaced four weeks apart. Each protocol comprised a 48-hour stay in a whole-room calorimeter, with the first day serving as a control period. On the second day, participants engaged in either post-meal walking for 15 minutes after each meal or 45 minutes of sustained walking performed at 10:30 in the morning or at 4:30 in the afternoon. All walking was performed on a treadmill at an easy-to-moderate pace. Participants ate standardized meals and their blood sugar levels were measured continuously over each 48 hour stay.  The researchers observed that the most effective time to go for a post-meal walk was after the evening meal. The exaggerated rise in blood sugar after this meal—often the largest of the day—often lasts well into the night and early morning and this was curbed significantly as soon as the participants started to walk on the treadmill.  The study authors write that: “Short, intermittent bouts of postmeal walking appear to be an effective way to control postprandial hyperglycemia in older people.”