A recent publication from the journal Diabetes Care reinforces the role of exercise in those with type 2 diabetes.
We generally know that cardiorespiratory fitness is associated with positive diabetes outcomes. This is great, as those who are able to participate in physical fitness activities can improve their cardiorespiratory fitness. The authors measure fitness by using VO2max, a measure of how much oxygen the body can use when exercising at the highest intensity possible. With training or better fitness, the body can more efficiently use oxygen, improving VO2max. But the authors wanted to know what mechanisms were linking cardiorespiratory fitness and blood sugar control.
With a group of over 300 people with type 2 diabetes, the authors ran through a battery of tests to assess physical fitness and diabetes measurements, including HbA1c, glucose tolerance, insulin sensitivity, and the disposition index. Disposition index is a measure of how well the beta cells can do their job in the face of decreasing insulin sensitivity.
It would be easy to assume something like the following: Exercise increases metabolism, which improves using sugar for energy, which support healthy blood sugar levels. However, by diving a bit deeper into the physiology of the situation, these authors are also showing that physical fitness is associated with improved insulin production.
The authors go on to point out that this reinforces the importance of exercise for those with type 2 diabetes in a new way. It appears that exercise supports maintaining the number of beta cells in those with pre-diabetes and type 2 diabetes.