Sugar During Exercise

There is a world of difference between sugar consumption in a person’s daily diet and sugar consumption during exercise but they often get lumped together with the message that sugar is ‘bad’. True in your diet; Not true for use during exercise.

In our daily diets sugar in the form of sweets, sugary drinks (soda, juice, sweet tea, sweet coffee drinks) is a major source of empty calories and most health organizations recommend limiting these added sugar to 25 grams/day. Compare that to the sugar content of: 12oz regular soda (40g), 12oz Frappuccino (45g), 16oz milk shake (131g), Chocolate Chip Cookie Sundae (224g). This amount of sugar as well as the excessive amounts of fat in these junk foods has contributed to an epidemic of obesity and associated chronic diseases.

Sugar is a carbohydrate most people over-consume. Fiber is a carbohydrate most people under consume and it is found in wholesome foods like beans, oatmeal or oat bran, quinoa, fresh fruit, and vegetables. Once digested these carbohydrate rich foods are converted to glucose (sugar) to fuel the activity of the brain, kidney and moving muscles. These foods are also high quality providing other substance the body needs: antioxidants, phytochemicals, minerals, vitamins, and water. As a distance runner these foods, rich in carbohydrate, are critical in your daily diet. During exercise however fiber slows digestion so lower fiber choices are better tolerated.

Sugar in sports beverages, blocks, and gels are designed to provide working muscles with carbohydrate in it’s most easily digested form. Consider that every hour you run, your body is consuming 30-60 grams of carbohydrate (or .7gram/kilogram body weight which is 48 grams for a 150 lb person). After 90 minutes of running most of the carbs stored in both the liver and muscle are reaching depletion. Consuming carbs during endurance exercise ensures the muscles are continuing to receive fuel. It is true that the body is also burning fat during exercise but that supply is abundant and there is no risk of running out of this form or fuel.

So it is up to you how you wish to fuel your body during your training runs and your race. Sports beverages, block and gels are not unhealthy choices and they are easy to carry and available on the race course. The Colfax Marathon will be serving Gatorade Endurance sports beverage, which has 14 grams or carbs per 8oz serving. If you prefer to eat other sources of carb rich foods (bananas, orange slices, pretzel, potatoes, tortilla) that is also a fine choice provided you have tested them on long training runs and found that they work for you.

Unfortunately many inactive people misunderstand the purpose of sports beverages and consume them as a beverage choice while sitting. In these cases that is an unhealthy choice! Here is a very funny video where a vendor refused to sell Gatorade to people who were not sweating: Watch video

Jacque Maldonado, MS, RD, CSSD, CDE
Jacque has a B.S. and M.S. in Nutrition and is an avid endurance athlete having finished four full Ironman® Triathlons and over 25 marathons including qualifying for Boston.  She is also a USA Triathlon coach Level 1 and a Certified Specialist in Sports Dietetics.  Jacque currently works in Kaiser Permanente’s Population & Prevention Services department.