Planning to run the Boston marathon this year? Having the proper fuel on board before the race can help you have a strong showing at the finish line. Carbohydrate loading is a helpful practice to maximize the stored energy in your muscle cells to carry you through the race.
How does it work?
Our muscles store carbohydrate in the form of glycogen for use during exercise. This is one of the fuel sources that sustain you through endurance exercise. Our muscles also rely on body fat and on what we eat and drink during exercise for fuel for the long haul. Carb loading helps you store more glycogen in preparation for the big day.
Tapering exercise the weeks before the event allows for optimal rest and recovery of muscle cells before the event. It also helps prevent last-minute injuries. Resting muscles use less fuel, so glycogen storage can take center stage.
How do you do it?
Keep your carb consumption to about 50-55% of your total calories a week before the event. Protein and heart-healthy fats should make up the balance of calories you need.
Increase your carb intake to 55-65% (3-5 g carb per pound body of weight) of daily calories three or four days before the event as you continue to decrease your exercise to allow for maximum glycogen storage. You might need to reduce protein and fat intake on these days so as not to exceed your calorie requirements. If you notice excess gas, try lower-fiber sources of carbohydrate. Too little fiber can cause constipation, so experimenting early in the week before race day will be helpful. Glycogen is stored in the muscle cells with water, so you might notice weight changes during your carb loading due to fluid shifts. As your muscles use this glycogen on race day, the water is freed up and helps prevent dehydration.
Consider working with a registered dietitian to coach you through your carb loading process. This is especially important if you have diabetes or blood sugar problems, be sure your blood sugar levels remain in a safe range.
Have a great race and we’ll see you at the finish line!
