Inactive adults who add a few hours of exercise each week may cut their risk of developing a pre-diabetic condition known as insulin resistance syndrome, even if they don’t lose weight.
As the population is eating more and exercising less, increasing numbers of adults and children are developing the syndrome, which results when a person loses the ability to use insulin effectively.
The syndrome can develop into type 2 diabetes and increase the risk of heart disease if left untreated.
To investigate whether physical activity influences the risk of insulin resistance syndrome, researchers followed 18 sedentary men and women for six months. Participants exercised by walking for 30 minutes between three and seven days a week and were told not to change their diets or body weights.
At the end of the study, researchers examined insulin sensitivity and levels of blood fats, such as cholesterol.
It was found that exercise with no weight loss increased insulin sensitivity.
According to researchers, even modest amounts of exercise, without weight loss or loss of abdominal fat, can improve indicators of glucose and fat metabolism among inactive, middle-aged adults, a group that is particularly at risk for developing type 2 diabetes.
Diabetes Care March 26, 2003;26:557-562
Exercise works by increasing the sensitivity of insulin receptors so the insulin that is present works much more effectively and your body doesnt need to produce as much.
Blood sugar is only the symptom in most diabetics; the real challenge is to control your insulin levels. Once the insulin levels are stabilized it is common for the blood sugar to come back to normal levels.
Most people, especially doctors, tend to not appreciate how powerful exercise is. However, I believe it needs to be viewed like a drug--you have to be very careful with the dose. If the dose is not high enough, it will not work.
One of the keys in using exercise to normalize insulin levels with secondary benefits of weight loss and normalization of blood sugars, is to make certain minimum thresholds are met. It is my experience that most people are not exercising enough.
Many thousands of people have told me they thought they were exercising enough when they were actually seriously under-dosed. Typically, Americans dont appreciate or understand optimum exercise. This may be because many have not previously competed in an aerobic sport, which allows you to understand the feelings of "training" and how hard you have to push yourself to obtain aerobic and insulin benefits.
There are three important variables with exercise:
- Length of time
Assuming people can exercise, I encourage my patients to gradually increase the amount of time they are exercising to one hour per day.
Initially the frequency is daily. This is a treatment dose until they normalize their weight or insulin levels. Once normalized, they will only need exercise three to four times per week.
The intensity is a bit tricky. I was one of the first to own a heart rate monitor many years ago, so I am more than familiar with them. I have never really found them too useful though. My general recommendation is far simpler and less expensive.
Exercise hard enough so that it is very difficult to talk to someone next to you. When you are exercising that hard your cardiovascular system is under such a significant stress that the mere act of talking makes you unable to provide your body with enough oxygen because of the diversion of airflow.
If you cannot carry on a conversation at all, then you have gone too far and need to decrease the intensity slightly. However, most people dont exercise at the appropriate intensity and as a result arent able to obtain the benefits.