What to Eat Before a Workout On a Keto Diet

We all know healthy eating is essential for your overall health and wellness. But exercise is the real game-changer.

It’s your stress-shredding, energy-surging, fat-incinerating, muscle-sculpting solution for conquering your goals, whether that’s dropping LBs or chiseling your ultimate physique.

So how do you fuel your body to push its limits? Should you opt for a small snack? A full, macro-rich meal? Or hit the gym in a fasted state?

Let’s explore the science of what to eat before a workout to answer these Qs and dish the best pre-workout nutrition for a ketogenic diet.

First Up: Should You Fast Before a Workout?  🤔

Fasted cardio or fasted training — hitting the gym on an empty stomach — has become a hot topic in the fitness world.

If you work out in the AM, your body’s glycogen stores (glucose/sugar reserves) are depleted after your overnight fast. So when you hit the rack, you force your body to tap into your fat stores for the energy it needs to push through your reps.[*] Burning through fat should theoretically lead to greater weight loss.

That’s a ketogenic diet in a nutshell. When your glucose stores are empty, your body switches to using ketones (fuel made from fat) as its primary source of energy.[*]

This explains why keto diets consistently slash body fat.[*][*] In one study, long-term keto-adaptation resulted in 59% higher fat-burning, an “extraordinarily high rate” of metabolism during exercise.[*]

Now for the Downsides...

Even though fasting may ignite your body’s flip to ketones and torch those love handles, it may come at a steep price for your fitness goals. Fasted exercise may:

Tank your performance. Dizzy spells mid-workout? Feeling sluggish, unmotivated, or nauseous? These signs scream that your body isn’t fat-adapted yet and needs some pre-workout fuel to achieve peak performance — especially if you’re engaging in high-intensity interval training (HIIT).

Sabotage muscle gains. If your body senses a lack of dietary protein, it may steal it from your muscles. So instead of building muscle during that sweat sesh, you’ll hinder hard-earn gains, weaken your muscle strength, and feel extra sore.

Noshing a pre-workout meal or snack can remedy these pitfalls. But are carbs the way to go?

Fighting the Carb Loading Juggernaut  👊

Why do most registered dietitians and nutritionists suggest eating whole-grain toast, bagels, pretzels, and other high-carb pre-workout snacks? Because they flood your body with glucose, raise your blood sugar levels, and supply a quick energy source.[*]

But when you’re in ketosis, your body relies on ketones for energy, not carbohydrates. So eating more dietary fat is the key to unlocking surging yet sustained energy levels. 

Then there’s the final macronutrient:

The Protein Power Play  💪

Protein gives your body essential amino acids: the building blocks of muscle and the champions of recovery.

Whether you’re strength training or sweating through an intense workout, physically demanding activities break down muscle fibers (which is why you feel sore the next day). 

Protein powers muscle protein synthesis (MPS) — the scientific term for muscle growth. MPS is how your body rebuilds bigger and stronger post-workout.

Skimp on protein, and you’ll never achieve the muscle gains you’re sweating for. Worse? Soreness, fatigue, and stalled progress will become your uninvited training partners.

The International Society of Sports Nutrition (ISSN) says eating 20–40 grams of a complete protein (with all essential amino acids) has been shown to "maximally stimulate" MPS.[*] It also significantly increases post-workout calorie-torching and fat-burning compared to fasting.[*]

So, now that we’re equipped with this intel about the benefits of higher fat and protein, let’s jump into:

What To Eat Before a Workout On Keto  ⛽

Experts recommend eating 30 minutes to 4 hours before your workout. According to researchers, eating 0.4–0.5 grams of protein per kilogram of lean body mass pre- and post-exercise is a simple, relatively fail-safe general guideline.[*]

The closer you are to exercising, the lighter your pre-workout snack. Conquering a monster workout? Snag a larger pre-workout meal way in advance to give your body ample time to digest and turn it into energy.

Strike the golden balance here — overstuffing yourself leads to sluggishness, while skimping on fuel leaves you gasping for gas mid-set. Give these ideas a go:

1. Keto Coffee Smoothies

The caffeine in coffee spikes your energy levels, attention, focus, and reaction times — essential perks for getting your head in the game and preventing injuries.[*][*] Blend up your java with MCT oil, and you’ll score a creamy, winning combo to optimize performance.

Medium-chain triglycerides (MCTs) are easily digested and rapidly converted to ketones, serving up a quick, efficient, steady energy source for your muscles and brain.[*] MCTs have been shown to:

• Elevate ketone levels [*]
• Enhance exercise performance and endurance [*][*]
• Significantly increase fat-burning during physical activity [*]
• Boost muscle strength via improved muscle energy production [*]

2. Protein Shakes (The OG)

Easy, portable, and endlessly customizable, protein shakes are a workout staple for good reason — as long as you put the right foods in (and leave out the carbs). Use these ingredients to create the best pre-workout protein shakes:

• High-quality plant-based or whey protein powder
• Unsweetened almond milk or full-fat coconut milk (for those MCTs!)
• No sugar-added nut butter (almond butter, cashew butter, peanut butter, etc.)
• Collagen for joint health
• Avocado for healthy, energizing fats
• Power greens or other low-carb veggies
• MCT oil
• Cacao powder
• Berries (optional for flavor)

According to the science of satiety, these ingredients blend healthy fats, protein, and vital nutrients to keep you feeling full and energized during your workout while supporting muscle growth and repair.

3. Full-Fat Cottage Cheese or Greek Yogurt

Sugar-free cottage cheese and Greek yogurt are loaded with casein protein. This protein is digested slowly to provide a steady source of amino acids to your muscles during and after exercise.

Besides improving muscle mass and performance, one study also revealed that consuming 25 grams of casein protein vs. an equal amount of whey protein resulted in more fat burning.[*][*]

Skip the low-fat options (usually loaded with sugar) and go full-fat here. 

Then top your dairy delight with a homemade granola that includes nuts, hemp seeds (a complete plant-based protein!), ground flaxseeds for hormonal health, unsweetened coconut flakes, unsweetened cacao nibs, or berries.

4. Fatty Fish

Tuna, salmon, sardines, and other fatty fish are rich in anti-inflammatory omega-3 fatty acids. These combat inflammation and oxidative stress caused by exercise, potentially reducing muscle soreness post-workout and speeding up recovery.[*] 

Studies also suggest they tout benefits for muscle mass, strength, physical performance, and MPS.[*]

5. Carnivore Charcuterie

A full pre-workout meal should include muscle-building and satiating animal protein, highly nutritious organ meats, or complete plant-based protein sources. 

When you’re on-the-go or opting for a lighter pre-workout snack, consider a grab bag of:

• Turkey, chicken, or roast beef roll-ups
• Cheese sticks
• Clean, grass-fed and finished beef jerky or wild-caught fish jerky
• Canned fatty fish (tuna, sardines, salmon, etc.)
• Nuts and seeds
• Keto Bricks!

6. Electrolytes

No pre-workout routine is complete without electrolytes. On a keto diet, you need more dietary electrolytes to maintain optimal fluid balance, muscle function, energy production, and hydration — especially during any type of exercise.

Being dehydrated by just 1–2% can decrease your physical and mental performance, tank your exercise endurance by 10%, and slow (if not prevent) MPS.[*][*][*]

Skip the fluorescent, sugary sports drinks and add a keto-friendly electrolyte supplement to your water bottle. Look for a balanced combo of sodium and potassium and bioavailable forms of magnesium. Drink this before, during, and after your workouts for best results.

7. Keto Bricks  🧱

Keto Bricks are shelf-stable performance bars with the perfect keto macros (81.5% fat; 12.5% protein; 6% carbs). Stash them in your gym bag for on-demand fuel or use them to make easy Keto Brick recipes (like pre-workout Peanut Butter Muffins!).

Unlike most protein bars, you won’t find any junk in our Bricks — only clean ingredients like:

• Grass-fed and pastured whey protein or superior-quality plant protein
• Raw, organic cacao butter (nature’s #1 source of fat-burning stearic acid!)
• Pure MCT oil powder (for more energy-elevating ketones)

Keto Bricks have been scientifically proven to raise ketone levels and encourage fat burning.[*] They’ll supply the healthy fats you need to dominate every workout!

Eat Like a Champion  👑

These keto-friendly pre-workout foods will fire up your energy levels and empower you to smash your goals, gain muscle, and torch fat. Experiment with different eating windows and food amounts to find your sweet spot for peak performance. You got this!

Forget the gym buddy who cancels last minute. Keto Bricks are your reliable partner, fueling your fitness journey and packing the nutritional punch you need to achieve your ultimate physique! 

🧱  Discover your favorite flavors and optimize your nutrition without compromise!