CrossFit Nutrition 101: How to Eat for Strength, Energy, and Recovery
The difference between simply surviving a WOD and truly thriving in CrossFit often comes down to what happens outside the box—specifically, what's on your plate. While many athletes focus intensely on perfecting their technique and increasing their training volume, nutrition remains the foundation that either supports or undermines these efforts.
Lexi Schmidt, a CrossFit head coach and performance nutritionist since 2017, understands this connection better than most. After discovering CrossFit in 2012, she quickly recognized how dramatically nutrition affected her performance in the gym. What began as personal experimentation with different nutritional approaches eventually led to professional certifications and launching her own nutrition practice in 2019, where she now specializes in both performance nutrition for CrossFit athletes and functional medicine approaches for hormonal and gut health issues.
With over a decade in the CrossFit community and years of experience as a nutritionist, Lexi has identified the common nutritional pitfalls that hold athletes back—and developed practical strategies to overcome them. Whether you're struggling with recovery between training sessions, hitting performance plateaus, or simply feeling less energetic than your training demands, the following nutrition principles can transform your CrossFit experience from the inside out.
Common Nutrition Mistakes CrossFit Athletes Make
Even dedicated CrossFit athletes can sabotage their performance through common nutritional missteps.
Underfueling
According to Lexi, the most prevalent issue she encounters is significant under-fueling.
"Under-eating is definitely one of the big things that I see," Lexi explains. "Especially if I have someone who wants to either lose weight or alter their body composition, their mindset is calorie deficit, calorie deficit." This mindset leads to diminished performance, poor recovery, and ultimately, stalled progress.
Determining appropriate caloric intake begins with accurate measurement. Lexi recommends a two-pronged approach: "If you have a smartwatch, that's a good baseline to determine how many calories you're expending throughout the day. They are not 100% accurate, but they give you a good starting point." Devices like Whoop, Fitbit, Apple Watch or Garmin provide valuable initial data.
For those without wearables, online calculators like tdee.net can help. Lexi educates clients on key metrics: "We have our BMR, our basal metabolic rate, and then our TDEE, our total daily energy expenditure." She explains that BMR represents "how many calories your body burns at rest. For most females, that might be between 1,200 to 1,600. For males, that could be between 1,600 to 2,200."
The total daily energy expenditure factors in your activity level. "Let's take into consideration what you're doing throughout the day. What kind of job do you have? Are you sedentary or moving all day? How often do you work out? How intense are your workouts?" These factors add calories on top of your BMR, making up your TDEE.
CrossFit athletes often drastically underestimate their needs. When Lexi investigates clients' actual intake, they frequently discover: "Yikes, I'm only eating 1,200 calories," despite burning significantly more. This creates a substantial energy deficit that undermines performance and recovery, requiring a careful approach to "refeed you and get you to increase your caloric intake" appropriately.
Following Trends
Another frequent mistake is blindly following nutrition trends without considering individual needs. "Being easily lured in by diet trends or labels on things" creates confusion for many CrossFit athletes who are eager to optimize their nutrition.
"If something says gluten-free, high protein, or keto on the front of the label, they think, 'oh, this must be healthy, so I'm gonna eat it,'" Lexi explains. However, these marketing terms often mask problematic ingredients. "When we look at the back ingredients, it's like, well, this is just a ton of chemicals."
Beyond misleading "healthy" marketing on foods, trends are often adopted without consideration for individual needs. "Why are you trying to be keto or low fat—is it even necessary for you?" Lexi challenges. The problem often stems from social media influence: "They'll say, 'well, someone on TikTok said blah blah blah,'" making decisions based on viral content rather than personalized nutritional science.
Misinterpreting Inflammation as Fat
Perhaps most surprising is how many CrossFit athletes misinterpret inflammation as stubborn body fat. "If I have someone who's like, 'I know there's muscle, I can feel it, but I have this layer of fat that just won't go away'—sometimes it's just inflammation and bloat," Lexi reveals.
This misdiagnosis sometimes leads athletes down frustrating paths of increased caloric restriction or excessive cardio when the real issue is dietary inflammation. Common culprits include "processed foods, gluten, processed dairy, processed sugar, processed oils," but the inflammation triggers can be highly individualized.
Even foods typically considered healthy might be problematic for specific individuals. "I've had people very sensitive to high amounts of cruciferous veggies, certain nuts or legumes, or eggs," Lexi notes. "I've seen some of the craziest food sensitivities—spicy foods or nightshade vegetables."
The solution often involves careful elimination and observation. "Sometimes we'll dig through their food log and ask, 'Are you noticing any GI issues or anything that could be indicating inflammation?'" When problematic foods are removed, the results can be dramatic: "More often than not, they come back and say, 'Whoa, I didn't eat this for a week, and what I thought was fat was bloat or inflammation around my midsection. I feel a lot leaner.'"
This revelation highlights why cookie-cutter nutrition plans fail many CrossFit athletes—individual inflammatory responses require personalized approaches to nutrition for optimal body composition and performance.
Protein: The Foundation of Performance
For CrossFit athletes seeking to improve performance and body composition, protein intake serves as the nutritional cornerstone. Lexi emphasizes that most athletes need to significantly adjust their macronutrient distribution to support their training demands.
"I like to make sure I'm getting people 25 to 30% of their calories from protein," Lexi explains. This target represents a substantial increase for many clients who come to her severely under-consuming this critical macronutrient.
Rather than obsessing over perfect macronutrient ratios, Lexi focuses clients on hitting specific protein targets first. She sometimes starts with clients by saying, "I don't care where your carbs and your fats fall, but I need you to hit your protein grams first and foremost." For many active individuals, this means aiming for substantial daily intake—"Maybe that's 130 grams of protein every day"—before filling in remaining calories from carbs and fats to get them to reach their daily caloric needs.
Practical Strategies to Increase Protein
Increasing protein consumption requires practical strategies that fit into busy lifestyles. Lexi recommends several approaches:
"I encourage people to use a food scale just so they can get a concept of just how much they are eating at each meal," she advises. "Sometimes people realize that they thought they were getting eight ounces, but they're really only getting three." This awareness often reveals significant protein shortfalls.
For those who struggle with consuming enough animal protein, Lexi suggests diversifying sources: "I really like to take advantage of things like cottage cheese, plain unsweetened Greek yogurt or Icelandic yogurt." Plant-based options can supplement intake as well: "If they tolerate lentils and legumes and beans really well, can we up your intake of those things?"
Simple meal additions can significantly boost protein content: "Incorporating an egg on top of a meal, or if you're doing two eggs, can you add in a half cup of egg whites just to boost that protein a little bit?" For convenient options, "I do love protein shakes and protein bars. I just make sure my clients are educated on selecting one that's a good quality."
Lexi emphasizes creative solutions beyond traditional protein sources: "There are a lot of great brands out there making protein cereals and protein granolas. I just recently found this protein granola that's super clean ingredients, with 12 grams of protein per serving. That's equivalent to two eggs."
Protein Timing: Does It Really Matter?
The fitness world has long debated the importance of protein timing, particularly around workouts. Lexi offers clarity on this often misunderstood topic, especially as it relates to CrossFit performance.
"Protein timing is something that's been recently studied again. There was a time where everyone focused on that 'post-workout window.' We thought that you needed to get a protein shake within twenty or thirty minutes for muscle recovery," Lexi explains. "But that has now been reframed a bit with the recent research that has come out."
For most CrossFit athletes, especially younger ones, the total daily protein intake matters more than precise timing. "As long as you're getting your protein in throughout the day, it almost really doesn't matter when we get it in," she notes. This gives athletes flexibility to structure meals around their schedules rather than obsessing over narrow post-workout windows.
However, age introduces an important variable to this equation. "Protein timing actually does become more important as you age. When we get to over 40, our muscle starts to break down," Lexi explains. While younger CrossFitters can focus simply on hitting their total daily protein targets, older athletes benefit from more deliberate protein distribution across meals to maximize muscle protein synthesis.
"I do like people in their 40s, 50s, and 60s to make sure that they're getting about 30 to 40 grams of protein per meal," she recommends. "Muscle protein synthesis becomes less efficient when we age. So spreading out protein throughout the day gets more important as we age."
This strategic protein distribution helps combat age-related muscle loss (sarcopenia) and supports recovery for masters athletes who need more nutritional support to maintain performance and muscle mass.
Pre and Post Workout Nutrition Strategy
While protein forms the foundation of a CrossFitter's overall nutrition plan, strategic fueling around workouts requires specific attention to carbohydrates and meal timing. Lexi's approach to workout nutrition emphasizes understanding the metabolic demands of CrossFit and tailoring intake accordingly.
Pre-Workout: Carbohydrate Focus for Glycogen-Fueled Performance
CrossFit's high-intensity nature primarily relies on glycogen as fuel, making carbohydrates essential for optimal performance. "For the most part, a CrossFitter is going to be more of a glycogen-fueled athlete because it's a high intensity sport," Lexi explains.
This metabolic reality shapes her pre-workout recommendations: "If you are going into a workout, carbs are going to give you the biggest bang for your buck in terms of energy." While some athletes experiment with fat adaptation, most CrossFitters perform best with adequate carbohydrate intake before training.
"Once our glycogen is depleted, our backup energy sources are fats," she notes. "Protein doesn't do a whole lot for fueling you during a workout."
Post-Workout: Balanced Recovery Approach
After the workout, recovery nutrition requires a more balanced approach that addresses multiple physiological needs. "That post-workout meal should be a well-rounded balance of all 3 macros; protein, carbs and healthy fats," Lexi advises.
The post-workout meal serves dual purposes: "You definitely want carbs just as much as you want protein. We want to restore the glycogen that we depleted by consuming more carbs, which also helps with soreness." Simultaneously, "we also want to facilitate muscle building by consuming protein in that meal."
Timing Considerations Based on Training Schedule
The timing of pre- and post-workout nutrition should be customized based on individual training schedules. "It comes down to what time of the day you are working out," Lexi explains. "Is it 5:30 AM? You could probably go in fasted. Is it 4:30 PM and you haven't eaten since lunch? Let's make sure you have a carb-based snack before the workout."
By strategically emphasizing carbohydrates before workouts, balancing nutrients after training, and adjusting timing based on individual schedules, CrossFit athletes can optimize both performance during workouts and recovery afterward—setting themselves up for consistent progress in the gym.
How Do I Know If My Nutrition is Working Well for Me?
The most powerful indicator of nutritional success comes from your body's own feedback signals. Lexi emphasizes that tracking these internal responses—what she calls "biofeedback"—provides crucial information for optimizing nutrition for CrossFit performance.
Key Biofeedback Indicators to Monitor
Lexi points to several indicators that point to problems in your nutrition:
Energy levels: "I like for people to pay attention to their energy levels throughout the day," Lexi explains. "Are you having these midmorning, midafternoon, midday crashes?" Lexi also points to reliance on caffeine as a red flag: "Are you relying on caffeine? Something's not working."
Sleep quality: "Are you struggling to fall asleep? Are you struggling to stay asleep? Are you struggling to wake up in the morning?" Even those who sleep through the night should assess whether they feel truly rested upon waking.
Workout performance and recovery: "Are you dragging yourself through a workout and then not recovering? Are you chronically sore?" These signals indicate potential nutritional deficiencies affecting both performance and adaptation.
Hunger patterns: "Are you either not hungry ever, or you are just ravenous?" Erratic hunger signals often reflect imbalanced nutrition.
By systematically tracking these indicators, athletes gain insights that numbers alone can't provide.
Signs Your Nutrition Plan Is Working
Positive shifts in biofeedback confirm effective nutritional strategies. Athletes who have made a positive change to their nutrition might notice that their "hunger seems way more regulated throughout the day, or their energy is more stable," Lexi notes.
Some other tangible improvements you might notice? Not feeling like you want to nap at 1PM anymore, not reaching for that second cup of coffee at 11AM, waking up without an alarm, and actually feeling rested.
For CrossFit athletes specifically, performance metrics provide additional confirmation: "Are you having to rest less between sets? Are you able to push through more burpees without stopping? Can you hit your percentages? Are you a little less sore than you were before?" These improvements validate nutritional changes.
When Does Professional Help Make Sense?
When should a CrossFitter seek professional guidance? Lexi identifies several key scenarios:
"If you've gotten to a point where you feel like you've tried a lot of things, or you're just so inundated with so much information that you're having a really hard time piecing out what's actually applicable to you," professional guidance can provide clarity.
Consistently low biofeedback scores also signal the need for help: "If on a scale of one to five, you're ranking all those biofeedback indicators a one or a two, it's probably time to sit down with a professional."
The ultimate indicator is quality of life impact: "Brain fog, low energy, poor sleep, poor performance—that's probably my definitive answer. Assess your biofeedback, maybe try to change something, reassess the biofeedback. And if you're like, 'yeah, something's not clicking,' then let's chat."
Lexi Schmidt is a certified Nutritionist and CrossFit Level 2 Trainer with a love and passion for all things health and wellness related.