Nutrition needs for cyclocross are driven by the energetic demand of high intensity training and racing. During the racing season, a good rule of thumb is to target ~8 grams of carbohydrate per kilogram of your body weight per day. For many racers, this amount of daily carbohydrate is adequate to support the type of training and recovery that's specific to cyclocross. Of course, some bigger training/racing days (including double-header race weekends) may necessitate even more carbohydrates, from 8-12 grams per kilogram per day.
While it's important to pay attention to your daily overall carbohydrate needs using the targets above, carbohydrate availability around training and racing is also important. Since cyclocross racing is relatively short and high intensity, and fueling is not typical during the event, it's imperative to have a solid pre-race fueling plan in place.
On a training day...
Aim for 2-4 grams of carbohydrate per kilogram of your body weight in the 2-4 hours before training. During training, take in ~60 grams of carbs per hour from your choice of sports drink, gels, and/or chews. ASAP after training, take in 1 gram of carbohydrate per kilogram of your body weight, and following training, aim to meet the remainder of your daily carbohydrate target by eating regular meals and snacks that provide nutritious complex carbohydrates (such as whole grains, beans, lentils, fruits, and vegetables).
On a race day...
Aim for 3-4 grams of carbohydrate per kilogram of your body weight 3-4 hours before the race and another 1 gram of carbohydrate per kilogram 1.5-2 hours before the race. Top off with ~30 grams carbohydrate just before the race with your choice of gel/chews and some sips of a sports drink. ASAP after the race, take in 1.2 grams of carbohydrate per kilogram of your body weight and aim to meet the remainder of your daily carbohydrate target by eating regular meals and snacks that provide nutritious complex carbohydrates (such as whole grains, beans, lentils, fruits, and vegetables). If you have another race the following day, you can eat small carbohydrate-based meals with 1-1.2 g/kg carbohydrate every 2-3 hours throughout the remainder of the day to reach 8-12 g/kg carbohydrate for the day.
Hydration on race day can be a challenge, so higher-sodium sports drinks can be used to pre-hydrate and rehydrate for the purpose of fluid retention and rapid rehydration between races. To pre-hydrate before a race, drink ~10 milliliters per kilogram of body weight of a high-sodium drink like Skratch Labs high sodium hydration 3 hours before the race. You can top off your pre-race hydration by drinking 5-10 milliliters of fluids (sports drink or sodium-containing drink) per kilogram of body weight about 2 hours before the race.
Cyclocross is a demanding sport, and meeting daily protein needs is helpful for daily recovery, health, and performance. Aim for 1.6 to 1.8 g/kg per day with moderate protein meals and snacks spread out throughout the day. Your pre-race meal can be lighter in protein, but aim to get 20-30 grams in your post-race recovery meal.
Sample pre-race intake
3-4 hours pre-race
Keep this meal low-fat and fiber. Moderate protein is ok as tolerated but keep it carb-focused. Here are some suggestions:
2-4 frozen waffles or 1-1.5 cups cooked rice
Maple syrup and sea salt (optional: tahini, pumpkin seeds, hemp seeds)
3 dates with 1 tsp nut butter
Bottle sports drink
2 hours pre-race
5 minutes pre-race
If you're looking to dial in your daily nutrition and race nutrition, check out the nutrition assessment I developed specifically for CX racers.