Carbo Loading

Carbohydrate loading is a technique used to maximize glycogen stores for long endurance competitions. Without careful planning, after a couple hours of strenuous activity, glucose stores can deplete causing dysfunction with the nervous system and will make continued exertion almost impossible. Let’s avoid this, yeah?

Thousands of studies have been conducted on this topic since carbohydrates were identified as the most efficient energy source over 80 years ago. Today the discovery goes on and on; does carbohydrate loading solely prevent fatigue? Can it actually improve performance? What is the best type: food, liquid, supplement? Does the timing of intake make a difference, etc. It’s overwhelming right now the piles of books, journals, and pages I have found just on this topic. For your sake, and my sanity, I am going to keep this basic.

I will begin by saying, that carbohydrate loading is pretty much unnecessary for athletes participating in events lasting less than 90 minutes. I mean, the orange slices at the soccer games, and spaghetti dinners the night before track meets are great, but the increasing load of carbohydrate intake days before an event and doubling your grams/kg/day amount is a little overboard.

So how does carbohydrate loading work? The key is to consume substantial amounts of carbohydrates a few days prior to the event and at the same time decrease the duration and intensity of training to assure plenty of endogenous glycogen stores. This sort of tricks your muscles into storing more glycogen and can possibly double muscle glycogen concentrations! Here is a good basic “how-to” chart.

Before the Event Training Intensity Training Duration  Dietary Carbohydrate
6 days Moderate (70% VO2 max)      90 min Normal (5g/kg body wt)
4-5 days Moderate      40 min Normal
2-3 days Moderate      20 min High-Carb (10g/kg body wt)
1 day Rest        — High-Carb

Some people (those who do not struggle with reactive hypoglycemia) do well to have a little bit of carbohydrates about 90 minutes before an event. Also, it is important to eat around 60 grams of carbohydrates immediately following activity to replete glycogen stores. And carbohydrate ingested during prolonged activity can help maintain blood glucose levels and even reduce the psychological perception of effort. Cool huh? This is when Gatorades and sports gu’s come in handy.

Those of you who exercise regularly and intensely, but do not fall under the endurance category, would do well to have a higher carbohydrate diet all around. 5-8 grams/kg/day is a good target for ya’ll.

SO…for some perspective, the following snack ideas provide around 60 grams of carbohydrates:

  • 16 oz sports drink and a small bagel
  • 2 pieces of toast with jelly
  • 8 oz pineapple juice and a granola bar
  • 1 large sweet potato w/ juice or sports drink
  • Other good concentrated carbohydrate foods include dried fruits, nectars, and athletic gu’s.