For most people with diabetes, exercise plays an important role in managing glucose (blood sugar). Control of glucose can help prevent many diabetic complications, including kidney and nerve damage. Exercise also reduces risk of cardiovascular complications, such as heart attack, high blood pressure and stroke.

The effect of exercise on blood sugar is complicated. It varies from one person to the next, and depends on several factors, such as:

• Duration of exercise
• Intensity of exercise
• Glucose level at the beginning of exercise
• Insulin levels at the beginning of exercise
• Degree of insulin resistance
• Level of hydration or dehydration 
• Personal physiology and metabolism

During exercise, the body transfers sugar from the blood into the muscle cells, where it is used as fuel. This process reduces the amount of glucose in the bloodstream. Additionally, regular exercise can improve the body’s response to insulin. Increased sensitivity helps insulin perform its work more efficiently.

Individuals with diabetes should pay particular attention to symptoms of too little glucose (hypoglycemia) or too much glucose (hyperglycemia) in the bloodstream. These symptoms may occur during and after exercise and must be monitored to prevent serious medical complications.