Exercise is important for diabetics because it helps you to

• improve your blood glucose control by using glucose more efficiently
• reduce your insulin or oral medication (tablets) requirements by helping your body cells take up glucose for energy
• strengthen your heart
• control your weight
• relieve stress.  

Precautions:

• Consult a doctor before you start any exercise programme.
• For Type 1 diabetics, check your blood glucose level before you start on your exercise and after you have exercised.
• Never exercise on an empty stomach. You may collapse. Have a snack about 1 to 3 hours before you exercise.
• Always carry some quick-acting source of sugar with you, such as sweets and glucose tablets. Such an item will come in handy if you experience low blood sugar during your exercise.
• Use proper-fitting footwear
• Slow down if you feel giddy, sweat profusely, your heart beats very hard and fast and you feel chest pains.