Beyond the Macros: Protein Truths and Carb Loading Strategy
In the latest solo Q&A episode of Real Fuel with SLS, Stevie Smith dives deep into two pillars of endurance nutrition: the "proteinification" of the modern diet and what carb loading REALLY is. Whether you're navigating the grocery store aisles or prepping for your next race, understanding these nuances behind these macronutrients is key to performance.
The "Proteinification" Trap: Quality vs. Marketing
The current food landscape is saturated with "proteinified" products—from protein ice cream to protein potato chips. While protein is essential for muscle repair, hormone production, and satiety, Stevie warns against the "more is always better" mindset.
What "High Protein" Actually Means
According to FDA standards, food labeling follows specific thresholds based on a Daily Value (DV) of 50g:
High / Rich / Excellent Source: Contains 20% or more of the DV (typically 10g+ per serving).
Good Source / Contains: Provides 10–19% of the DV.
More Protein: At least 10% more of the DV than a reference food.
The Quality Gap (PDCAAS)
Not all protein is created equal. Scientists use the Protein Digestibility Corrected Amino Acid Score (PDCAAS) to measure quality on a scale of 0 to 1.0.
Score of 1.0: High-quality proteins like whey, egg whites, and soy isolate.
Lower Scores: Many plant-based sources or "proteinified" additives may have lower digestibility or incomplete amino acid profiles.
The Takeaway: 10g of protein from cottage cheese is not the same as 10g from a processed protein chip. Relying on "proteinified" snacks often means missing out on fiber and vital micronutrients found in whole foods.
The Fiber Gap: What We’re Actually Missing
While culture is obsessed with protein, 90% of Americans are falling short on fiber. Why does fiber matter? Fiber promotes digestive regularity, prevents constipation, and feeds beneficial gut bacteria. It also aids in weight management by increasing satiety, helps control blood sugar levels, lowers cholesterol, and reduces the risk of heart disease, diabetes, and certain cancers
Women's Goal: 25g per day
Men's Goal: 38g per day
Carb Loading: Filling the "Glycogen Tank"
For endurance athletes, overdoing protein can lead to early satiety, making it impossible to hit the carbohydrate targets necessary for performance, recovery, and health. But when should you carb load? If your race or event lasts longer than 90 minutes, a protocol is warranted to maximize your glycogen stores (your body's preferred, high-efficiency fuel).
Carb Load Protocol:
Target: 8–12g of carbohydrates per kilogram of body weight.
Timeline: 2–4 days preceding the event.
Why it works: Your body can store roughly 2,000 calories of glycogen. Proper loading ensures you don't "hit the wall" or bonk during the late stages of a race.
And you shouldn’t save carb-loading just for race day. Practicing your carb load in your peak weeks before the race will help you find what foods work for you and allow your gut to tolerate the amount of carbs needed for an effective carb load.
Stevie’s Favorite "Fuel" Hacks
When hitting high carb numbers feels difficult, Stevie recommends:
Orange Juice: Or any other juice—a liquid carb source that is easy on the stomach and doesn’t take up much ‘space’ is a great way to increase carbs.
Sour Patch Watermelons: A personal favorite for big training days and carb loading.
Top Takeaways
The "Proteinification" of food is a marketing trap: Just because a label says "High Protein" doesn't mean it’s a "health food."
The quality gap: Companies often use lower-quality protein sources to hit those numbers. Stevie emphasizes the PDCAAS score, which measures how well your body actually digests and uses specific proteins.
The trade-off: When you fill up on "proteinified" chips or ice cream, you often miss out on fiber and critical micronutrients (like the Omega-3s in salmon or Vitamin D in dairy).
If your endurance event is going to last longer than 90 minutes, you need a formal carb load to prevent "bonking" or hitting the wall.
The protocol: Aim for 8–12g of carbs per kilogram of body weight for 2–4 days before your race.
Pro-tip: If eating that much volume is hard, use "liquid gold" like orange juice or simple sweets like Sour Patch Kids to hit your numbers without feeling overly stuffed.
Too much protein can sabotage endurance performance: For athletes, more protein isn't always better. Because protein is highly satiating (it keeps you full), eating too much of it during a race build-up can make it physically impossible to eat enough carbohydrates.
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