The ketogenic and low carb diet craze has exploded over the past 3-4 years. This is for great reason. Ketogenic dieting has been shown to improve weight and weight loss efforts, reduce inflammation, and be a therapy for metabolic disease such as diabetes and cancer. There is even evidence supporting it use in neurodegenerative diseases such as epilepsy and Alzheimers. However, how do you properly eat prior to training on a ketogenic diet?
It is very common for bodybuilders and all athletes to consume high amounts of carbs and protein prior to training. This is because in normal individuals following a western type diet (standard bodybuilding diet), carbohydrates are the primary fuel source because carbs supply energy to the muscles and brain. Only rarely does fat and protein contribute as a primary fuel source to individuals who are carb adapted. This is not a blanket statement, however, for purpose of this article, carb adapted individuals run primarily on carbs and fat adapted individuals function primarily on fat. Check out my article on Metabolic Flexibility if you would like to learn more about how your body uses different types of energy sources. When talking about preworkout on keto, the approach is much different.
The Bodybuilding Norm
Above discussed why it is common for athletes to consume high amounts of carbohydrates prior to training; what does the research say about this? During exercise, the body converts food consumed into adenosine triphosphate or ATP. Under normal circumstances, the ATP is produced from the carbohydrate glucose. Glucose goes through a metabolic process known as glycolysis. If the intensity of the exercise is very high, glycolysis will also produce lactate (i.e., lactic acid), which is what causes the burning sensation when training. The lactate is recycled back into glycolysis to sustain exercise. As most know, as soon as the burning sensation becomes too intense, exercise cannot be continued. On the other hand, if exercise intensity is not high, glycolysis will feed into a process known as the Kreb Cycle and then the Electron Transport Chain. These are very complex topics that can be further explained in this article on energy systems, however, for the purpose of this article, know that carbohydrates produce and the ability to produce energy is predicated on the intensity of the exercise.
With all of this being said, athletes consume high amounts of carbohydrates to fuel their training. As is now known, carbs produce energy and a lack of carbs may not be able to sustain exercise. When carbohydrates are consumed in adequate amounts they are stored in the body as glycogen. Think of glycogen as a fuel tank; the body only uses it when it is needed (e.g., the car is running). If too much carbohydrate is consumed, the excess will be stored as fat. Therefore, the amount of carbohydrate needed is contingent on the athlete, sport, and intensity of the training. Now we introduce fat.
The Importance of Fat
In the last section, carbohydrates were discussed in detail, but where does fat play a role. We discussed the Kreb Cycle and Electron Transport Chain briefly, although, this is where fat plays a crucial role. Fat will feed into these energy systems with carbohydrates to produce high amounts of energy. To look at it in perspective, one carbohydrate molecule will produce 36-38 ATP whereas one fat molecule will product 130 ATP. It is known fat is more calorie dense than carbohydrates (9 calories/gram vs 4 calories/gram). Therefore, this is where the calorie density of each macronutrient becomes relevant.
When exercising at a low intensity, fat will feed into the production of energy and intensity can be sustained for longer. If the intensity exceeds what fat can contribute, the breakdown of fat to fuel movement is slowed. If carbohydrate availability before or during training is low, fat contribution to exercise will increase. On the other hand, if carbohydrate availability is high, then the contribution of fat to sustain exercise will be low. With this being said, it seems ketogenic dieting may be detrimental to exercise, but that is hardly the case.
Ketones to the Rescue
Ketones are produced when the body follows a ketogenic diet, has been in a fasted state, or has diabetes2,3. The last situation is called diabetic ketoacidosis and is irrelevant to this article because it is a clinical problem that should be addressed by a physician. Read more about the ketogenic diet here where I breakdown the ketogenic diet in its entirety. Although, ketones can provide energy to fuel both muscle and the brain when training.
In short, a ketogenic diet is when one is consuming 70-60% of their calories from fat, 20-30% from protein, and <5% from carbohydrates. This will foster a situation where the liver produces the three ketone bodies acetoacetate (AcAC), acetone, and beta-hydroxybutyrate (BHB) in the process known as ketogenesis from stored and dietary fat. BHB and acetoacetate are the primary ketone bodies used to feed the brain and peripheral tissue4. Ketones possess many health benefits because they are able to increase satiety, reduce inflammation, and act as an adjuvant therapy in neurodegenerative diseases. The ketogenic diet forces an individual to follow a different preworkout meal plan.
Preworkout on Keto
When on a ketogenic diet, preworkout nutrition will be high in fat, moderate in protein, and, and extremely low in carbohydrates. It would also be in the best interest of the ketogenic athlete to consume fats such as coconut oil, butter, and MCT oil because these fats are high in a fat known as Medium Chain Triglycerides (MCTs). MCTs can easily be converted to ketones because they are shorter chain fats than common fats such as olive oil and corn oil, which are considered long chain triglycerides (LCTs)5.
Therefore, a common preworkout meal on keto could be coffee with 1 tablespoon of coconut and MCT oil with a scoop of whey protein such as Myo100. This type of meal would supply sufficient energy from the coconut and MCT oil as well as a high quality protein source from the Myo100. If following a ketogenic diet, this meal would be extremely beneficial to sustaining performance and increasing cognitive acuity. Compared to a preworkout meal of an individual on a standard western diet, a ketogenic preworkout meal is much different. However, if one is adpated to the ketogenic diet, this meal will provide much benefit to their training session.
In conclusion, a ketogenic diet is a very high fat, low carbohydrate diet that requires a different approach to prewrkout nutrition. Normally, athletes will use high amounts of carbohydrates prior to training to sustain their performance. On a ketogenic diet, the same athlete would have to consume high amounts of fat because they are changing how their body produces energy. Therefore, the ketogenic athlete has to be more intuitive as to how to they program their nutrition around training.
- Coyle, E. F., Jeukendrup, A. E., Wagenmakers, A. J., & Saris, W. H. (1997). Fatty acid oxidation is directly regulated by carbohydrate metabolism during exercise. American Journal of Physiology-Endocrinology And Metabolism, 273(2), E268-E275.
- Bergqvist, A. C., Schall, J. I., Gallagher, P. R., Cnaan, A., & Stallings, V. A. (2005). Fasting versus gradual initiation of the ketogenic diet: a prospective, randomized clinical trial of efficacy. Epilepsia, 46(11), 1810-1819.
- Kerl, M. E. (2001). Diabetic ketoacidosis: pathophysiology and clinical and laboratory presentation. Compendium, 23(3), 220-228.
- Wilson, J. M., Lowery, R. P., Roberts, M. D., Sharp, M. H., Joy, J. M., Shields, K. A., … & D’agostino, D. (2017). The Effects of Ketogenic Dieting on Body Composition, Strength, Power, and Hormonal Profiles in Resistance Training Males. The Journal of Strength & Conditioning Research.
- Courchesne-Loyer, A., Fortier, M., Tremblay-Mercier, J., Chouinard-Watkins, R., Roy, M., Nugent, S., … & Cunnane, S. C. (2013). Stimulation of mild, sustained ketonemia by medium-chain triacylglycerols in healthy humans: estimated potential contribution to brain energy metabolism. Nutrition, 29(4), 635-640.