If you have diabetes, your doctor may have told you in so many words to get moving. That’s because regular exercise—a brisk, 30-minute walk several times a week, for example—may be as effective as diet and medication in controlling blood sugar levels. Harvard researchers report that exercise triggers a chemical called AMP kinase, which spurs muscles to use more glucose. The result: lower blood-sugar levels, an effect that can last up to 24 hours after an exercise session. And because exercise helps insulin work more efficiently, people with diabetes who work out faithfully may require less insulin or oral medication.
Play it safe by drinking plenty of water before, during and after your activity, wearing protective padding and warming up and cooling down. You should also…
• Consult your doctor. Discuss your best exercise options. For example, if you have foot problems, swimming or gardening may be safer than walking. If you have vision problems, high-impact activities like running or jumping rope should be avoided as they can rupture blood vessels in the eye.
• Check your feet. Before exercising, wash and bandage any irritated areas.
• Monitor blood-glucose levels. If you take insulin or oral diabetes medication, test your blood sugar twice before exercising—about one hour before and again 30 minutes before starting. If your blood sugar is dropping, you may need a highcarbohydrate snack. For most, the safe pre-exercise blood glucose range is 100 mg/dl to 250 mg/dl. Never exercise if your fasting blood glucose exceeds 300 mg/dl. Ask your doctor what’s best for you.
• Test during and after, especially if you are starting a fitness program, a new activity or switching to a different intensity. This will help predict how the exercise will affect your blood sugar. You may need to pare your insulin or drug dosage in response.
• Time it right. Plan to exercise about one to three hours after a meal. This ensures your body will have enough glucose to fuel your muscles. Avoid working out when insulin is at its peak to prevent low blood sugar.
• Be prepared. Carry snacks in case your blood sugar starts to fall. Juice, raisins or glucose tablets are portable sources of fast-acting sugar.
• Tell a buddy. Working out with a friend who is aware of your condition can motivate and protect you. If you play a team sport, make sure everyone knows what to do in case of emergency.