Low levels of physical activity — like the 5,000 steps per day that Americans typically achieve, which is only about half of the recommended amount — have been implicated in the development of insulin resistance and its progression to full blown type 2 diabetes. However, the studies that suggested this connection were performed under laboratory conditions; they did not use people eating real meals, and they did not assess glycemic variability, so the direct impact of physical activity on glycemic control is not completely clear.
Elevated postprandial glucose (PPG) often precedes the development of type 2 diabetes, and is a risk factor for adverse cardiovascular events, independently of diabetes status. Thus, Dr. Catherine Mikus and her colleagues at the University of Missouri set out to precisely define the impact of reducing physical activity on PPG and glycemic variability in healthy, active volunteers as they went about their daily lives. The results of their study were recently published in the journal Medicine and Science in Sports and Exercise .