Combining powerful presses and explosive cleans with rapid-fire rounds of swings, dips, and jumps is hard work. But for CrossFit enthusiasts, it’s just another normal day at the gym. Even a single 10-minute metcon (metabolic conditioning) can be a brutal experience that tests your body’s muscles and energy systems to the max.
So what’s the best way to prepare your body for this onslaught? Aside from what you bring mentally, it comes down to nutrition—and in particular, carbohydrates. You need lots of energy to fuel short, high-intensity workouts. The longer the workout, the more energy you need.
If you’ve been combining paleo-style eating with CrossFit but largely skipping the starches—a common approach—it’s time to rethink your CrossFit carbohydrate strategy.
Low-Carb May Leave Gains on the Table
Your body uses carbs stored in your muscles (glycogen) and carbs floating around in your blood (as glucose from your last meal) to power you through your workout. Once you’ve used up a lot of that available glycogen and glucose, your body starts looking for ways to conserve energy. What happens next? Increased fatigue, and decreased focus, power, and strength. Over time, those all lead to impaired results.
Yes, there is research tying a low-carb, higher-fat diet to enhanced performance.[1,2] However, the studies focus on endurance, which relies more on fat as a fuel source. As anyone who has been in a box recently can tell you, there’s a big difference between running a marathon and powering through a high-intensity CrossFit workout.
Not only are low-carb, higher-fat diets less than ideal for WODs and power-focused training, they can actually make high-intensity workouts harder. That’s partly because fats slow down your body’s ability to burn carbs.[3,4] And since fat provides energy at a much slower rate than carbs, you may finish your WOD long before the energy benefits of those fats kick in.
How to Match Your Carbs to Your Training
CrossFit athletes are often highly committed to their training, so it’s not unusual for them to not only do the workout of the day, but also more accessory work, additional skill or strength practice, or even an extra metcon. Suddenly, that already-tough 30-minute workout becomes an hour-long rampage that has your body crying out for more fuel.
Carbs are “muscle sparing,” which means when your body has enough of them, it won’t draw as many amino acids from muscle tissue for fuel. This becomes more important as your workout reaches the one-hour point and beyond.
To find out just how much energy you need, start by assigning a level to each of your workouts. Refer to the guidelines below for CrossFit-specific examples of “light,” “moderate,” and “hard” training sessions. In the course of a week, your workout intensity may vary. Just stay consistent in how you label each one.
- 30-60 minutes
- Strength/skill WOD + one metcon
- 60-90 minutes
- WOD + extra metcon/accessory work
- 90+ minutes (total in a day)
- 2-3 skill/movement WODs + 1-2 metcons
How Many Carbs Belong in Your CrossFit Nutrition Plan?
Now it’s time to assign the number of carbs you need for each workout level. I know that counting macros sounds more “bodybuilder” than “CrossFitter,” but if you’re serious about your training, it’s worth considering. Think of it this way: When high-level athletic performance is a central part of your life, you owe it to yourself to use the tools at your disposal.
Just like Goldilocks wanted everything “just right,” you need to do the same with your carbohydrates. If you eat too few, you won’t perform your best, and you’ll put your hard-earned muscle at risk. Eat too many, and your body composition may head more toward fat and less toward muscle. And every pound of fat you gain is an extra one you have to pull up to the bar!
- Non-training day: 0.5-0.75 grams of carbs per pound of body weight per day
- Light workout: 1.0 grams of carbs per pound of body weight per day
- Moderate workout: 1.5 grams of carbs per pound of body weight per day
- Hard workout: 2.0 grams of carbs per pound of body weight per day
Maximize Fuel Availability
The kinds of carbohydrates you choose and when you eat them during the day are up to you. But if you’re looking to crush your workouts, I recommend eating the majority of your carbs shortly before and after your workout.
And don’t forget that you can drink carbs during training, too. It’s common to diss Gatorade and other sports drinks these days, but they were made for hard-training athletes in this type of situation.
- Lambert, E. V., Speechly, D. P., Dennis, S. C., & Noakes, T. D. (1994). Enhanced endurance in trained cyclists during moderate intensity exercise following 2 weeks adaptation to a high fat diet. European Journal of Applied Physiology and Occupational Physiology, 69(4), 287-293.
- Higashida, K., & Higuchi, M. (2015). High Fat Diet and Endurance Exercise Performance. Sports Performance (pp. 151-156). Springer Japan.
- Havemann, L., West, S. J., Goedecke, J. H., Macdonald, I. A., Gibson, A. S. C., Noakes, T. D., & Lambert, E. V. (2006). Fat adaptation followed by carbohydrate loading compromises high-intensity sprint performance. Journal of Applied Physiology, 100(1), 194-202.
- Stellingwerff, T., Spriet, L. L., Watt, M. J., Kimber, N. E., Hargreaves, M., Hawley, J. A., & Burke, L. M. (2006). Decreased PDH activation and glycogenolysis during exercise following fat adaptation with carbohydrate restoration. American Journal of Physiology-Endocrinology and Metabolism, 290(2), E380-E388.