Subscribe to Dr. Mirkin's free FITNESS & HEALTH NEWSLETTER
Race Longer with a Low-Glycemic-Index Meal

The Glycemic Index measures how high blood sugar levels rise 30 to 120 minutes after eating a particular food or combination of foods. A study from Loughborough University in England shows that athletes in sports events lasting more than a couple hours may benefit from a pre-competition meal that has a low glycemic index (American Journal of Clinical Nutrition, August 2006).

How long you can exercise a muscle without hurting depends on how much sugar you can store in that muscle and how long you can keep that sugar in the muscle during competition. Just about everyone agrees that taking extra carbohydrates for two or there days prior to an endurance competition can help fill your muscles maximally with stored sugar and therefore increase endurance. A well-trained athlete can also fill his muscles maximally with sugar just by cutting back on workouts for a few days prior to competition, no matter what he eats.

Since it takes up to 24 hours to fill your muscles maximally with sugar, the pre-race meal is not used for that purpose. This new study showed that a low-glycemic index meal taken three hours prior to competition may help an athlete to exercise longer by causing muscles to use more fat, and less sugar, for energy. While nobody really knows why, the most likely explanation is that when blood sugar levels rise too high, the pancreas releases huge amounts of insulin. Insulin drives sugar into cells and causes cells to burn more sugar. This uses up sugar more quickly. On the other hand, the low-glycemic meal does not cause a high rise in insulin, so muscle burn more fat, preserve their stored sugar supply and can be exercised longer. More on the Glycemic Index


Reports from

How can I raise my HDL (good) cholesterol?
Is it normal to stop breathing during sleep?
How can I strengthen a painful shoulder?


Dear Dr. Mirkin: Is high blood pressure during exercise dangerous?

People with normal resting blood pressures who develop very high blood pressure during exercise are the ones most likely to develop high blood pressure later on. These people have arteries that do not expand as much as normal arteries when blood is pumped to them. When your heart beats, it squeezes blood from inside its chambers to the large arteries. This causes normal arteries to expand like balloons. If the arteries do not expand enough when blood enters them, blood pressure can rise very high.

Normal blood pressure is 120 when the heart contracts and 80 when it relaxes. During exercise, the heart beats with increased force to raise blood pressure. It is normal for blood pressure to rise up to 200 over 80 during running, and to 300 over 200 while doing a leg press with very heavy weights. If your blood pressure rises much above 200 during running, you are at increased risk for developing high blood pressure. You should go on a heart attack prevention program that includes a diet low in saturated fats and refined carbohydrates, regular exercise, losing weight if you are overweight, not smoking, and avoiding stimulants and drugs that raise blood pressure. Check with your doctor. More


Dear Dr. Mirkin: Will taking creatine supplements help to prevent the loss of muscle strength that occurs with aging?

Each muscle has millions of muscle fibers, and each muscle fiber is innervated by a single nerve. With aging, you lose nerves and with loss of each motor nerve, you lose the corresponding muscle fiber. So the treatment of muscle weakness with aging is to increase the size and strength of each remaining active muscle fibers. You do this only by exercising against increasing resistance.

Creatine will do nothing to stop the progressive loss of nerves that decreases the number of active muscle fibers. However, it can help you to exercise harder and longer, so it may help you to do the intense workouts that will build larger and stronger muscles. At this time we do not know whether there are any deleterious side effects in older people from taking creatine, so I cannot recommend it. More


Pumpkin Recipes!
Pumpkins and the winter squashes are interchangeable in recipes. Use cooking pumpkins, not jack-o-lantern pumpkins, which lack flavor and tend to be stringy. Here are some of Diana’s favorite recipes for cooking pumpkins or winter squash.

Tagine with Pumpkin and Vegetables (a lovely veggie stew)
Squash Chili
Three Sisters Soup

You'll find lots of recipes and helpful tips in The Good Food Book - it's FREE

June 26th, 2013
|   Share this Report!

About the Author: Gabe Mirkin, MD

Sports medicine doctor, fitness guru and long-time radio host Gabe Mirkin, M.D., brings you news and tips for your healthful lifestyle. A practicing physician for more than 50 years and a radio talk show host for 25 years, Dr. Mirkin is a graduate of Harvard University and Baylor University College of Medicine. He is board-certified in four specialties: Sports Medicine, Allergy and Immunology, Pediatrics and Pediatric Immunology. The Dr. Mirkin Show, his call-in show on fitness and health, was syndicated in more than 120 cities. Read More
Subscribe to Dr. Mirkin's free FITNESS & HEALTH NEWSLETTER
Copyright 2019 Drmirkin | All Rights Reserved | Powered by Xindesigns