By: Nick Harden
Summer is coming, and if you’re like most people, you want to lean down and look your best for beach season. But with so many diets and "schools of thought" out there, how do you know which one will actually get you the results you want?
At the end of the day, the most important factor for fat loss is a calorie deficit—consuming fewer calories than you burn. No matter how you structure your diet, if you’re not in a calorie deficit, fat loss won’t happen. That said, if your goal isn’t just to lose weight but to retain muscle and look strong and lean, the way you go about dieting becomes incredibly important.
One of the biggest decisions people make when dieting is whether to follow a high-carb or low-carb approach (which includes keto and carnivore). These are two of the most popular methods right now, and which one you choose will have a major impact on both your physique and your strength levels.
But before we begin, let’s briefly talk about body composition and the scale.
The Scale Lies—Focus on Body Composition
When it comes to the scale, we often get attached to “numbers” we want to see. For example, if you weigh ~200 lbs, you might think, “I’ll look so much better if I lose 20 lbs!”
The problem is, most people assume that losing weight automatically means losing fat. But the number on the scale reflects more than just body fat—it includes muscle, water, and other tissues. Hypothetically, if you put on 3 lbs of muscle and lost 5 lbs of fat, you’d only see a net difference of ~2 lbs lost on the scale! For those of us who actively resistance train with the goal of putting on muscle, this absolutely needs to be taken into consideration.
That’s why understanding our terms is so important when it comes to the scale and body composition. If we start with the wrong baseline, we won’t properly understand the results we’re seeing. For that reason, the scale shouldn’t be your only measure of progress. Non-scale victories—such as how you look in the mirror, how clothing fits, how your performance in the gym is going, and more—are all important variables to keep in mind.
So how does keto affect your body composition? Let me explain.
The Problem With Keto: Artificial Loss, Muscle, Performance & Brain Fog
Why Keto Makes You Lose Weight (But Not the Right Kind)
A ketogenic diet often leads to rapid weight loss—but not for the reasons most people think. The biggest drop in weight comes from losing water and glycogen (the stored form of carbohydrates in your muscles). Since every gram of glycogen binds to about 3 grams of water, cutting carbs means your muscles shrink and lose volume.
Sure, the scale moves—but at what cost? Without glycogen, your muscles appear flat and deflated, and your overall body composition suffers. If your goal is to look full, strong, and lean, keto works against you.
And unfortunately, the moment you reintroduce carbs, your muscles rapidly soak them up, replenish glycogen stores, and retain water again. This can cause a noticeable weight spike, but it’s not fat—it’s simply your muscles restoring their natural fullness.
Many people misinterpret this as fat gain, reinforcing the myth that carbs make you “bloated” or “fat.” In reality, they’re restoring what was lost—lean mass and hydration—which is essential for muscle performance and overall aesthetics.
Muscle & Performance Impact
Carbohydrates are the body’s most efficient energy source for high-intensity training. Glycogen provides faster and more efficient energy than fat ever can. This is crucial because high-intensity activities—whether sprinting, lifting heavy weights, or doing endurance sports—rely primarily on glycogen. Without it, your strength and endurance will be severely limited. Simply put, if you’re running on fat alone, you’re handicapping your ability to train hard and build muscle effectively.
Additionally, when glycogen levels are low, an enzyme called AMPK is activated. AMPK prioritizes conserving energy rather than using it to build new muscle. Worse, it inhibits mTOR, the enzyme responsible for muscle growth. So not only does keto limit your performance, but it also makes it harder for your body to recover and grow stronger over time.
Brain Function & Strength Connection
Your brain also heavily depends on carbohydrates. Approximately 80% of the energy needed for neurons comes from carbohydrates, meaning when you restrict carbs, your neurons don’t perform as well. This is why people on keto often experience “brain fog”—their central nervous system isn’t operating at full capacity.
This has major implications for your strength. Your ability to produce force isn’t just about muscle; it starts with the nervous system sending strong, fast signals to the muscles. When the brain is under-fueled, your reaction times slow, coordination suffers, and ultimately, your strength and athletic performance decline.
Instead of getting stronger and more defined, you’re increasing the likelihood of muscle breakdown and reduced neurological efficiency. If your goal is to look athletic, powerful, and lean, keto is working against you.
Why Carbs Are Your Best Friend for a Lean, Muscular Look
If you want to look strong, defined, and full of energy, a carb-rich diet is the way to go. Carbs fuel your workouts, keep your muscles looking full, and help you perform at your best in the gym. Instead of feeling depleted and weak, you’ll train harder, recover faster, and look your absolute best.
In contrast, keto may leave you feeling sluggish, weak, and struggling to maintain your performance.
A Real-Life Transformation: Jared Feather & Tristyn Lee
Still not convinced? Let’s look at a real-world example from our own team. Coach Jared Feather worked with Tristyn Lee, an athlete who had been following a strict carnivore/keto diet. Despite his incredible work ethic, he found himself struggling with muscle fullness, performance, and overall energy levels. His strength and endurance weren’t where they should have been, and despite his lean physique, he didn’t feel his best.
When Jared transitioned him to a high-carb diet, the benefits were undeniable:
- He looked fuller and more muscular – Restocking glycogen allowed his muscles to retain more water and appear rounder and more defined.
- His strength skyrocketed – With muscle glycogen replenished and ample carbs fueling his nervous system, he was able to lift heavier and train harder than before.
- His energy levels drastically improved – No more brain fog, no more sluggish training sessions. He could train harder and recover faster, making his workouts exponentially more effective.
This transformation is a perfect real-world demonstration of why carbs are irreplaceable when it comes to looking and performing your best. When you fuel your body correctly, the results speak for themselves.
Check out RP's transformation video where Mike interviews Jared & Tristyn to get all the details on what they did and what the experience/transformation was like.
So, Now What?
We now know that a higher-carb diet is best for body composition and performance. But what do we do with this information on our way to a successful transformation?
Because there’s so much variability in our lifestyles and training, it’s challenging to tell you exactly how many carbs you should eat. So here’s a simple macro framework you can personalize:
Using the approach above, you might find you feel much better than you did on a lower-carb diet. In fact, even if you’re eating carbs, you may not be eating enough carbs to truly thrive.
Once you’ve set your macros, chart your weigh-ins 2–4 times per week. Insert a trendline into your chart and observe your rate of loss (ideally ~0.5–1.0% of body weight per week). Based on your trend, all you’ll mostly need to adjust is your carbs—since protein and fat are set.
That’s it! You’ll be on your way to getting the jacked physique of your dreams and turning heads at the beach before you know it.
The Bottom Line
Want to get shredded for summer while keeping your strength, energy, and performance at their peak? Don’t fear carbs—embrace them. They’re essential for fueling your workouts, maintaining muscle, and achieving that full, lean, and powerful look.
Set your macros, chart your weigh-ins with a trendline, adhere to the plan, and look forward to turning every head on the beach this summer.
Need help refining your diet to get the summer body of your dreams while ensuring you have plenty of carbs and great training? With 1:1 coaching, I’ll help you optimize your nutrition and training so you can maximize performance, recover faster, and step on the mat feeling strong and prepared.
No more second-guessing your meal timing, macros, or energy levels. Together, we’ll create a simple, effective plan tailored to your goals—whether you’re cutting for competition, building strength, or just striving for peak performance.
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