Your blood sugar level (BSL) determines how good you feel, and a low level is a source of stress. Blood glucose is your brain’s only fuel, and the brain monitors this carefully. When the level gets even a bit too low, negative hormones increase, lowering motivation. When BSL is adequate, the receptor cells receive good messages, and positive attitude hormones transmit positive messages throughout the mind–body network. If you eat too much sugar, starch, or other simple carbohydrate, your BSL can rise too high. You’ll feel really good for a while. But the excess sugar triggers a release of insulin, which can push BSL too low. In this state, your reflex brain is under stress and reduces blood flow to the frontal lobe, resulting in foggy thinking. If the BSL is not raised, negative peptides are produced, lowering motivation and energy level.
When BSL is maintained at a stable level throughout the day, you will be more motivated to do most activities, including exercise. You’ll have a more positive mental attitude and will be more likely to deal with stress and problem solving. Just as eating at regular intervals throughout the day maintains metabolism, the steady infusion of balanced nutrients all day long will maintain stable blood sugar levels, sending positive peptide messages between the body and mind that everything is OK.
See my books Women’s Complete Guide to Running, Running and Fat Burning for Women, or Nutrition for Runners for more meal planning information.
If your BSL is low, the simple act of eating a snack containing 80 % simple carbohydrate and about 20 % protein 30 minutes or less before your workout will boost the BSL and stimulate positive peptides, improving attitude and helping you to get out the door.
Eat every two to three hours
When exercisers experiment with various snacks, most find that an individualized arrangement of small meals produces a more stable BSL.
Do I have to eat before a workout?
Only if the BSL is low. Most who exercise in the morning don’t need to eat anything before the start. As mentioned, if your blood sugar level is low in the afternoon and you have a workout scheduled, a BSL snack can help. If you feel that a morning snack will help, the only issue is to avoid consuming so much that you get an upset stomach.
For best results in raising blood sugar levels when they are too low (within 30 minutes before exercise), try different snacks. The product Accelerade has worked best among the thousands of exercisers I hear from every year. It has the 80 %:20 % ratio of carb to protein. If you eat an energy bar with the 80:20 ratio, be sure to drink 6 to 8 ounces of water at the same time.
Eating during exercise
Most exercisers don’t need to worry about eating or drinking during a run or walk until the length of the session exceeds 60 minutes (for most of my clients, 90 minutes). At this point, there are several options.
On runs longer than an hour, many runners like to use a BSL booster. Practice various eating strategies on your long run-walks and pick what works best.
Rule of thumb: 30 to 40 calories every 2 miles.
Gel products—These come in small packets and are the consistency of honey or thick syrup. The most successful way to take them is to put one to two packets into a small plastic bottle with a pop-top. About every 10 to 15 minutes, take a squirt or two, with a sip or two of water.
Energy bars—Cut a bar into 8 to 10 pieces and take a piece with a couple of sips of water every 10 to 15 minutes
Candy/sugar—When consumed during exercise, sugary snacks have produced the quickest boosting effect among the runners I’ve monitored. The usual consumption is 30 to 40 calories about every 10 to 15 minutes
Sports drinks—Since there is significant percentage of nausea episodes among those who drink these during exercise, this is not my top recommendation. If you have found that a product works for you, use it exactly as you have used it before.
Reload within 30 minutes after exercise
Whenever you have finished a hard or long workout (for you), a reloading snack of 100 to 300 calories will help you recover faster. Products with 80 % simple carbs and 20 % protein have been shown to be most successful in reloading the muscles. The product that has worked best among the thousands I work with each year is Endurox R4.