Sports drinks, gels, bars, Fig Newtons, bananas, sweet potatoes, peanut-butter-and-jelly sandwiches and even pizza have all been used as sources of nutrition for various endurance events lasting over four hours. At a minimum, we will want to clarify our needs from a caloric standpoint.
Muscles store carbohydrate as glycogen (long-term stored energy). This glycogen energy source is tapped out at about 2,000 calories for a trained triathlete. Why is this important? Because this fuel source is only good for about 1.5-2 hours of high-intensity performance. So, for those of you with plans on racing events that will end in about 1.5 hours, race-day nutrition isn’t as critical as for those competing in events lasting more than 2 hours. In a situation like the CrossFit Games, the replenishment of calories becomes the burden, not fueling during competition.
Pre-Competition Nutrition—CrossFit Endurance
Assuming an event will last three hours or more, the same protocol as shown above is appropriate. The goal is the same: consuming a measured ratio of macronutrients with a carbohydrate bias to top off one’s glycogen stores.
Assuming an event will last three hours or more, the same protocol as shown above is appropriate. The goal is the same: consuming a measured ratio of macronutrients with a carbohydrate bias to top off one’s glycogen stores.
In-Competition Nutrition—CrossFit Endurance
Now that you are aware of how much energy your body can store (approximately 2,000 calories), we need to identify how many calories are being burnt and how to replace those calories to perform between three and 17 hours. Caloric burn rates can vary anywhere between 400-750 calories per hour depending on the specific individual and effort being given.
Now that you are aware of how much energy your body can store (approximately 2,000 calories), we need to identify how many calories are being burnt and how to replace those calories to perform between three and 17 hours. Caloric burn rates can vary anywhere between 400-750 calories per hour depending on the specific individual and effort being given.
The second part of our equation is identifying how many calories our bodies can process and turn into energy in that same time period. This again can vary between 300-550 calories per hour. Confirming this number is very personal and should be established during training rides or runs. Success begins by starting with about 300 calories per hour (for a 140-170 lb. male) and monitoring your energy levels both during and after exercise. The following information can be reviewed to see how the body demands more protein and fat as the time of an event increases.
90 Minutes-4 Hours
Glycogen is depleted.
Fueling transitions to glucose/carbohydrate.
Isotonics or gel/water should be the source of calories.
Target should be 300 calories per hour/20 oz. of water.
Electrolytes begin to have larger role.
Glycogen is depleted.
Fueling transitions to glucose/carbohydrate.
Isotonics or gel/water should be the source of calories.
Target should be 300 calories per hour/20 oz. of water.
Electrolytes begin to have larger role.
4-12 Hours
Intensity trends lower.
Fueling moves from glucose to fat.
Carbohydrate loading must continue to fuel fat burning.
Electrolytes must be replaced at 500-2,000 milligrams
per hour.
12-18 Hours
Carbohydrate contributes 50 percent of energy vs. 80 percent at lower levels.
Protein is now needed to provide approximately 10 percent of calories.
Fat now bears a 20-35 percent burden of total calories.
Electrolyte and water prescription remains the same as in the 4-12 hour period.
Total consumption is 300-600 calories per hour and breakdown is 60-70 percent carbohydrates, 20-30
percent fat, 10-15 percent protein.
Potassium should be replaced once every 3-4 hrs (via electrolytes or bananas).
Total consumption is 300-600 calories per hour and breakdown is 60-70 percent carbohydrates, 20-30
percent fat, 10-15 percent protein.
Potassium should be replaced once every 3-4 hrs (via electrolytes or bananas).
Don't be a fool
Finally, here are a couple of “watch outs” and thoughts around deviating from this program. For those of you thinking you can simply down all your calories at the beginning of each hour, think again. If you flood your digestive tract with too many calories, you will force your heart to pump a disproportionate amount of blood to your stomach. This takes vital blood away from the muscles you need to compete.
At the other end of the spectrum, training at 90-95 percent max of your maximum heart rate (or rate of perceived exertion) will disallow proper digestion as your body will flow a disproportionate amount of blood to your muscles and away from your stomach. This is the cause of so many “reversals” (or vomiting), which cause so many longer distance athletes to lose vital nutrition and consequently
DNF.
DNF.
For those procrastinators trying to catch up in your race by loading up on nutrition missed at previous occasions, you will likely meet the same end as those trying to “forward buy” their nutrition. So, measured, methodical introduction of calories and measured, methodical use of those calories (60-80 percent of max heart rate or RPE) will ensure your fuel is processed and used as economically and efficiently as possible.