With type 2 diabetes, patients may want to get the most health benefits from exercise. You need to fuel yourself before, during, and after exercise.
If diabetes can be managed through diet and exercise alone, then patients do not need a preexercise refill compared to patients without diabetes. However, if you are taking insulin or taking medications that promote insulin production by the pancreas, you may need to think about it a little before you eat.
The choice of a pre-exercise energy-boosting food depends on the following:
- Pre-exercise blood glucose levels;
- Expected duration of exercise;
- The time of day you plan to exercise;
- The body’s response to exercise.
Before exercise
Glucose testing should be performed. If the blood glucose reading is between 200 and 300 mg/dl and you have already eaten at least 1 meal during the day, you may not need to take any food supplements. However, if the blood glucose reading is above 250 mg/dl, it may be necessary to check for ketone bodies. Ketone bodies are produced when the body burns fat instead of sugar as fuel. Do not participate in exercise if ketone bodies are present in your body. If your blood glucose level is over 300 mg/dl, ask your doctor if you can exercise.
Otherwise, eat an extra meal with 15 to 30 grams of carbohydrate. The lower your blood glucose is before you start exercising and the longer you plan to exercise, the more you should add, even up to 30 grams of carbohydrate. It may be necessary to try a variety of types and amounts of foods to see which ones are most appropriate.
The following additional meals provide 15 grams of carbohydrate and require only simple preparation:
- 1 Small piece of fresh fruit
- 1 small piece of fresh fruit (about 110 g);
- 1 slice of bread (about 30 grams) or 1 slice (about 15 cm) of tortilla;
- half cup of oatmeal;
- 2/3 cup plain nonfat yogurt or yogurt with added sugar substitute.
The following foods contain 30 grams of carbohydrates:
- 1/2 peanut butter sandwich (1 slice of whole wheat bread with 1 tablespoon of peanut butter) and 1 cup of milk;
- 1 English muffin and 1 teaspoon low-fat margarine;
- 3/4 cup whole grains, ready-to-eat cereal and 1/2 cup nonfat milk.
If your blood glucose level is below 150 mg/dl and you plan to exercise for at least 1 hour, you can choose a small amount of protein as an extra meal. The following foods contain protein and less than 5 grams of carbohydrate:
- 15 almonds;
- 1 tablespoon of peanut butter;
- 1 hard-boiled egg;
- Slice of hand-rolled cheese.
Many people with diabetes find that a 3 gram carbohydrate to 1 gram protein ratio works best as an addition to a meal. No additional protein is needed. The food already contains enough protein.
The morning exercise diet
If you like to exercise in the morning, make sure you eat breakfast first, regardless of your blood glucose level. Exercising in the morning on an empty stomach can raise blood sugar. However, food signals the pancreas to produce insulin, which keeps blood sugar at a safe level.
If you are using insulin or diabetes medication, ask your doctor if you need to make any adjustments to your exercise.
Adding a meal plan for prolonged exercise
Take some snacks with you if you are going out for a ride, running a marathon, or going on an all-day hike. If you are participating in a race, it may not be easy to carry food with you. Glucose gels and tablets or sports drinks may be good options. As with meals, be sure to count the amount of carbohydrates you consume.
Tip: The body can absorb carbohydrates faster if they are in liquids and gels. These foods can come in handy if you need to put your best foot forward.
Check your blood sugar every hour. The amount of carbohydrate in a refill meal depends on how long you plan to exercise and on your blood glucose reading. The right idea for a refill meal is to consume enough carbohydrate to avoid low blood glucose levels or loss of strength, but not so much carbohydrate that blood glucose levels spike. It may take some experimentation to find the right balance.
Post-exercise meal plan
Take another blood glucose test. If the blood glucose level is below 100 mg/dl, add 1 additional meal. If the next planned meal or refill is 30 to 60 minutes later, 15 grams of carbohydrate should keep blood glucose at normal levels. If a planned meal or refill is an hour later, about 5 grams of carbohydrate and 7 or 8 grams of protein are needed.
Blood glucose levels may drop after moderate or vigorous exercise and continue for 24 hours. If your blood glucose level is still below 100 mg/dl at bedtime, double the amount of extra meals. If taking insulin, ask your doctor if you can lower your dose at bedtime.
Even if you don’t need to add a meal after exercise, you still need to regain energy to help your muscles recover. The best time to eat is between 30 minutes and 2 hours after exercise.