Exercising is one of the best ways to enhance a keto lifestyle, not to mention to improve overall health and wellness. But since it’s long been believed that carbs are critical for workout energy, one of the most common questions from people on a keto diet is how to fuel the body for exercise without carb loading. In this article, we clear up the confusion and share information on what you should eat before and after a workout for optimal performance and recovery while on a ketogenic diet.
The Fact and Fiction of Carb Loading for Exercise
It was a long-held belief that carbohydrates are required to fuel and recover from exercise. But recent research by scientists and physicians such as Dr. Jeff Volek (a registered dietitian, professor at Ohio State University, and keto expert), provide a better understanding of the physiology of the body. The consensus? Carbohydrates are not the only fuel source the body can use during and after exercise. In fact, his studies suggest carbs are perhaps not even the optimal source, and that a higher fat, low-carb diet has more promising results for pre- and post-workout meals. These findings are the reason you may be hearing about more athletes and people dedicated to an active lifestyle following a keto or low-carb diet rather than a low-fat diet or other diet.
Still, despite these long held common misconceptions, there is some truth in the need for eating before and after working out. In the nutrition world, this is called peri-workout nutrition.
What is Peri-Workout Nutrition?
Simply put, peri-workout nutrition is the nutrition around your workout, or what you eat before exercise to fuel your performance and what you eat after exercise to facilitate recovery.
Standard recommendations for peri-workout nutrition are based on false pretenses that carbohydrates are essential for performance but also recovery. This leads many people to “carb load” before and after exercise.
On a ketogenic diet, where carbs are essentially off limits, carb loading obviously isn’t an option. But that doesn’t mean your energy or performance has to suffer.
What Should I Eat Before I Workout?
Here’s the truth: your body does not need carbohydrates to perform. In fact, on a keto diet, your body doesn’t need any pre-workout food or even a keto-friendly sports drink in order to maintain stamina; you can workout on an empty stomach. And this is true for every type of body composition! That’s one of the beautiful things about being keto; when you’re in ketosis, your body is in prime fat-burning mode. This means that during exercise, your body can tap into stored body fat for workout fuel. In fact, studies have shown that ketogenic dieters burn over twice as much fat during exercise compared to those fueling themselves with carbs. So, if your primary goal is fat burning, not eating before exercise may be a great way to maximize your efforts.
However, not everyone exercises with fat burning in mind or wants to exercise without fueling up first. To those people wondering what to eat before a workout, we have great news: You can eat whatever keto-friendly foods you know nourishes your individual body and allows you to maintain enough energy and achieve your exercise goals.
If you’re not sure what those are, follow these guidelines:
- Eat protein: it’s great to include before exercise because it gives your muscles the amino acids it needs to perform and repair themselves during exercise, not to mention build muscle.
- Eat fat: it’s your primary energy source on a ketogenic diet, so adding fat before exercise gives your body more energy to call on.
- Eat a full meal, if that works for you: Though not everyone can stomach a big meal before exercising, a full meal before a workout ensures you get enough grams of fat and grams of protein to fuel performance. If your personal preference is a meal, even one including keto-friendly veggies, go for it.
- Or drink a protein shake or smoothie with MCTs: It’ll ensure you have a fast-digesting protein and fat source your body can access shortly after eating, without having to worry about being too full to perform.
What to Eat After a Workout?
Whether you’re keto or not, post-workout nutrition is an important factor for how well your body handles workout recovery. During this time, post-workout snacks are in order, and protein is your best friend.
Protein is often under-consumed on a ketogenic diet because our classic recommendations are to eat 20 to 25 percent of our calories from protein to maintain ketosis. Although these guidelines were developed for children suffering from epilepsy, they continue to be recommended (along with 5 to 10 percent daily calories from carbs) because they represent a baseline for people wanting to get and stay in ketosis, meaning pretty much anyone who stays within these guidelines should be able to get into and maintain ketosis. But because every body is different, what actually works for you depends on your body and your lifestyle. For example, if you exercise intensely via cardio, weights, or otherwise on a regular basis, you need more protein (more on that below, but also see Dr. Marc Bubbs’ book Peak: The New Science of Athletic Performance That is Revolutionizing Sports).
Many people fear eating excess protein on a ketogenic diet because they think it will be converted to glucose in the body and potentially kick you out of ketosis. While this can occur, this conversion is a demand-driven process, meaning your body only converts protein to glucose when it needs glucose for uses such as cells in the body that can only use glucose for energy (e.g. red blood cells) or to help replenish glycogen (our bodies stored form of carbohydrates) after exercise.
Regardless, you shouldn’t fear protein consumption, especially since many ketogenic dieters don’t eat enough of it even when they’re not exercising.
While getting enough protein is something you should focus on anyway, getting enough is even more important if you exercise. Research shows that consuming just 20 percent of your calories from protein while exercising can lead to muscle loss. This tells us that your body requires more protein if you are exercising, likely closer to 30 percent of your calories or more depending on your individual body. Plus, right after you exercise, your body is ready to soak in nutrients for recovery, especially protein. This is why reaching for a quick, refueling keto-friendly protein shake on your way home from the gym may be your best option.
But it’s just as important to note that choosing the right protein source after a workout is also essential. You need something that is fast-digesting during your post-workout window, which starts right after your workout and extends up to 24 hours. Whey protein, which comes from dairy, is the fastest-digesting protein powder, and when taken after exercise, it can stimulate muscle-protein synthesis, or the building of new muscle. This matters because muscle-protein synthesis is essential for recovery and preventing sore muscles.
People avoiding lactose from dairy can still get the benefits of whey protein by choosing a protein powder containing whey protein isolate (aka whey isolate, a dietary supplement that separates components from milk), which contains the lowest amounts of lactose.
Once you’ve nourished your body with rapidly digesting protein, you’re ready for a full meal. After you get home from the gym, prepare a high-protein and higher fat meal to make sure that you are continuing to focus on protein intake and getting all of the micronutrients from quality fat sources. Both will help facilitate recovery.
The Final Word
The most important thing to take away from this article is to not fear protein consumption. The traditional low-protein recommendations for keto are based on epilepsy treatment and should be modified to fit your own bio-individuality and lifestyle. Bottom line: if you’re exercising, you need more protein, especially after exercise.