There's nothing worse than doing everything right (or so you think) and having your blood glucose levels running high inexplicably. The problem may be that many different factors can affect your insulin action (whether it's insulin your body releases or insulin you inject or pump), and you may or may not be controlling for all of them equally well.
What we do know is that most athletic individuals have lower levels of insulin and require less insulin release for carbohydrate and other food intake, meaning that their bodies are very sensitive to insulin. Having low fasting insulin levels (assuming it is not due to a deficiency) is associated with greater longevity, as demonstrated by the fact that most 100-year-olds without diabetes exhibit this trait. Keeping insulin needs lower also reduces your risk for heart disease, high blood pressure, certain cancers, and more.
So what can you do to keep your insulin action high? Almost any type of physical training can make your insulin work better. Resistance training results in enhancements in your muscle mass, allowing for greater overall glucose uptake. Aerobic training generally does not increase muscle mass as much, but that type of activity can enhance muscular uptake of blood glucose.
The effects of aerobic exercise on insulin action usually start to decline within 1-2 days, however, and regular aerobic activity is essential to keeping it higher. Increasing your overall muscle mass may have a more lasting effect by allowing for greater glucose storage in muscle (an insulin-sensitive tissue) and increasing the total amount of glucose you can dispose of through glycogen storage. Muscles have a limit to how much they can store, and having more muscle mass results in a greater potential storage capacity.
Myriad factors can improve your body’s insulin action and making control blood glucose levels easier with less insulin. Don’t try just adding some or more exercise in. For optimal results, try to improve your body’s insulin action by several of these means as their effects are likely to add together to result in a greater overall effect.
Factors That Can Improve Insulin Action:
Regular aerobic and resistance exercise
Muscle mass gain
Loss of body fat—particularly intra-abdominal (visceral) fat, extra fat stored in the liver, and possibly some of the excess fat in muscles
Improved blood glucose control (and avoidance of highs and lows)
Reduced levels of circulating triglycerides and free fatty acids (fats in blood)
Reduction in low-level, systemic inflammation (with physical activity and antioxidants)
More effective leptin action (hormone released by fat), causing reduced food intake
Reduction in mental (anxiety, depression) and/or physical (illness, etc.) stressors
Control of physical (illness, infections, severe muscle soreness, etc.) stressors
Decrease in circulating levels of cortisol (released by physical and mental stressors)
Increased testosterone levels in men
Intake of more dietary fiber, less trans fat, and fewer highly refined foods
Daily consumption of a healthy breakfast
Adequate dietary intake of key vitamins and minerals, such as magnesium
Lower caffeine intake
Adequate sleep (seven to eight hours a night for most adults)
Effective treatment of sleep apnea
Use of insulin-sensitizing oral medications (like Avandia or Actos)