Exercise plays a vital role in the prevention and treatment of diabetes. 90 to 95% of people generally have type 2 diabetes. We will thus mainly focus on type 2 diabetes.
Type 2 diabetes once known as adult-onset or non-insulin-dependent diabetes is a condition that is recognized by chronic high glycemia or elevated blood glucose levels. It is however not any longer known as adult-onset because of the increase in obesity among children and further development of type 2 diabetes in early ages.
The basic reason for type 2 diabetes is that an individual becomes insulin resistant.
Blood Glucose Levels
- If an individual’s fasting levels are below 100 mg/dl of blood, they are considered normal.
- Blood glucose between 100 to 125 mg/dl of blood is a pre-diabetic condition.
- Fasting levels above 125 mg/dl of blood is a full diabetic condition.
The cases of Type-2 diabetics have increased exponentially in the last decade. In India, there are more than 73 million cases of Type-2 diabetes in adults. About 30 million cases are pre-diabetic. Not surprisingly the prevalence of Type-2 diabetics closely tracks that of increasing rates of obesity. The accumulation of visceral fat located within the abdominal cavity that surrounds important internal organs can lead to Type-2 diabetes.
Common Symptoms of Type-2 Diabetes
- Thirst and hunger
- Vision changes or blurred vision
- Excess urine
- Frequent Infection and slow healing sores.
The complications associated with type-2 are very serious and many. There is a 5 to 30 folds increased risk of retinopathy with eventual blindness, nephropathy or kidney disease, neuropathy or diabetic nerve pain, and lower-limb amputations. Diabetes can also advance coronary heart disease and stroke.
Modifiable and Non-Modifiable Factors
When we investigate modifiable risk factors for developing Type-2 diabetes, we find physical inactivity at the top of the list followed by obesity. Other modifiable risk factors are hypertension and elevated cholesterol levels.
Non-modifiable risk factors for Type-2 diabetes include the history of generational diabetes, race/ ethnicity, age over 45 years, and family history of diabetes.
What Causes Type-2 Diabetes?
The primary cause of diabetes is insulin resistance. When insulin binds to the receptor located on the surface of the cell membrane, it generates a signal which opens channels of the cell membrane and allows glucose to enter the cells from the blood. It is believed that the problems in this signal are responsible for insulin resistance. As skeletal muscle is the major depot of blood glucose after a meal, insulin resistance in muscles will chronically increase blood glucose levels and hyperglycemia.
Diagnosis of insulin resistance can be easily made by an oral glucose tolerance test in which after all night a measured dose of glucose is given and the rate at which glucose clears the blood is measured over time. A non-diabetic individual will clear the glucose within 90 minutes. However, a diabetic person will take much longer as due to insulin resistance glucose will take much longer to clear from the blood.
Benefits Of Regular Exercise
Regular exercise can help in the prevention and control of Type-2 in two ways.
First, a single bout of exercise can reduce blood glucose levels to a significant level. When we exercise, continuous muscular contractions stimulate the extraction of glucose from the blood for fuel thereby normalizing blood glucose levels.
Second, regular exercise will increase insulin sensitivity in the blood thereby decreasing insulin resistance. It is also observed that exercise benefits in lowering blood glucose levels even during the resting period.
Both aerobic and strength training have equal effects on blood glucose levels. Thus regular participation in all forms of exercise will have a dramatic effect of reducing insulin resistance in all populations contributing to both prevention and treatment of Type-2 diabetes. There is no medication, pill, or any medical procedure that can come close to benefit of exercise. In fact, people who have non-modifiable factors can also delay the onset or prevent Type-2 diabetes if they follow a regular exercise routine.