Most of us have heard of carb loading as a way to prepare for a sporting event, but many of us don’t really know what it is, how it works, and why it’s only appropriate at certain times, and for certain kinds of athletes.
Most of us have heard of carb loading as a way to prepare for a sporting event, but many of us don’t really know what it is, how it works and why it’s only appropriate at certain times — and for certain kinds of athletes.
“Carb loading is a strategy used very commonly by long distance runners, swimmers, triathletes and individuals who are participating in activities that are normally going to be high intensity and long duration,” said Dr. Jennifer Gourdin, a sports medicine physician with Kaiser Permanente, in Silver Spring, Maryland.
In general, when preparing for an event, such as a 26.2 mile marathon, carb loading is a process to boost the amount of fuel stored in muscles.
“Carbs are stored in our body as glycogen in the muscle and liver,” said Gourdin. “We need the glycogen in order to perform during these long duration, high intensity events.”
Gourdin said loading up on carbohydrates in a systematic way “is a way to increase your glycogen stores in your body, so you’re less likely to fatigue, and you can also improve your performance during the long duration activities.”
What’s the right amount of carbs?
“We recommend that you consume between 8 to 12 grams of carbohydrate per kilogram of body weight per day,” said Gourdin. “And you distribute that amount of carbohydrates over the course of your meals and snacks throughout the day.”
She said first-time half-marathon runners make the common mistake of eating a carb-laden meal the night before a long race.
“You should start carb loading at least two to three days in advance leading up to your activity, so that you can build up those glycogen stores,” said Gourdin. “And, during that carb loading period you have to reduce your training volume and intensity, because if you don’t you’ll just burn off the carbs you’ve been intaking and you won’t store it up in that glycogen form.”
And importantly, “Carb loading is not intended for the short duration activities, like a casual workout, or pickup basketball game,” said Gourdin, who also doles out knowledge on TikTok and Instagram under the handle @drjthesportsdoc.
If you’re looking to improve your energy in a short period of physical activity, she added: “You can just eat a small snack — like a banana — 30 minutes before. That’s not considered carb loading, that’s just giving you that little added boost or push that you need for your activity.”
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