Effects of Progressive Intensity Exercise Training on Glycemic Control in Older Adults

Approximately 25% of older adults have type 2 diabetes mellitus, and almost 50% of older adults have prediabetes. Identifying strategies to prevent the progression of diabetes in this older adult population is imperative. One strategy that has shown promise is lifestyle modification. As adults age they also increase sedentary behavior, decrease physical activity, and have increased occurrence of sleep problems. The combination of these lifestyle factors are likely responsible for the decreases in glycemic control with aging. The American Diabetes Association recommends that prediabetic adults, including older adults, increase structured aerobic exercise and incidental (non-exercise) physical activity while decreasing sedentary behavior. It is emphasized that structured exercise is the most important of these recommendations. However, initiating an exercise routine, may unintentionally affect time spent sitting, non-exercise physical activity, and other lifestyle behaviors like sleep. These changes may attenuate or enhance the effects of exercise on glycemic control. This study will compare the effects of moderate and high intensity exercise on glycemic control, and determine whether changes in non-exercise physical activity, sitting time, and sleep are associated with the observed changes. Because of the increasing prevalence of diabetes with age, identifying the optimal exercise prescription to preserve glycemic control in older adults has important clinical implications.