I have now survived for over a month on the ketogenic diet. It is an extreme form of a low carbohydrate high fat (LCHF) diet. My interest in the diet is in teaching my body to use fat as an energy source rather than carbs during endurance training and racing. I set out to experiment with this nutrition plan for a minimum of four weeks. My goal was to become “keto adapted.” Essentially teaching my body to burn fat through an alternate metabolic process (rather than using carbs for energy). Here is my report for weeks 4 and 5. Check here for my previous posts on this topic.
Over the last two weeks, I was able to keep a fairly consistent daily intake of carbs. My average daily intake of net carbs (total carbs minus fiber) was 29 g with no day over 40 g.
My fat/protein/carb balance remained good. My target has been to get my calories in a ratio of approximately 70:20:10 from fat/protein/carb. My average daily calorie intake was about 2600 cal/day. That had me taking in around 210 g of fat per day. My calorie requirement will be increasing to >3000 cal/day now that I am back in training mode. So that will increase my fat intake to 250 g or more per day.
Another metric I have been tracking is my protein intake as it relates to my body weight. The ketogenic diet is not a high protein diet. One source I found indicated that an intake of 1.8-2.0 grams/kg of body weight is a good target. This is consistent with the 20% of calories from protein intake mentioned above. For me at 70 kg (165 lbs), that is around 130-140 g for a 2600 calorie intake. My average daily intake of protein over the two-week period was 130 g.
I finally got the nerve up to try Bulletproof coffee. This is a concoction consisting of coffee, butter, and MCT oil (medium chain triglycerides commonly found in coconut oil). The mixture is blended (I use a handheld immersion blender) and served hot. The original creation is found here. My homemade version was made with 10 ounces of coffee, one tablespoon unsalted butter, and one tablespoon MCT oil (purchased from Whole Foods). This provides around 340 calories and around 40 g of fat. I have to say that it actually tastes really good and gives a nice boost of fat and calories.
In general, I am very selective in the supplements I take. With the ketogenic diet, it is important to take in enough electrolytes. Potassium and magnesium intake has been a challenge for me. I just was not getting enough from the foods. I had already been using MgSport for my magnesium supplement. I wrote about the importance of magnesium here. For potassium, I found a product from Emergen-C called ElectroMix. I have been mixing one packet in with 32 ounces of water and I get 408 mg of potassium (in addition to some calcium and magnesium). And, of course, I ALWAYS take my Base Salts during exercise.
Another concern is to make sure I am getting adequate nutrients for maximum performance, recovery after workouts and to maintain and build muscle. Amino acids are critical for this. I can get amino acids from protein sources, but I also use Base Amino as a great supplement for amino acids.
You may be wondering how I am tracking all of my nutrition data. I have been using an app called MyFitnessPal. The app allows me to track all of my nutritional information by simply inputting my meals into the daily tracker. One feature that I love is the ability to use the built-in barcode scanner to scan the product UPC barcode. This automatically captures all of the nutrition information (most of the time) and all you have to do is enter the number of servings. One word of caution: make sure the nutrition information makes sense. I have noticed that it is generally very accurate for most entries, but occasionally I find errors or things left out. For example, I have be tracking potassium intake and I have noticed that sometimes products I know have potassium in them (e.g. spinach) indicate zero when the barcode is scanned.
Another feature that is great about MyFitnessPal is that it snycs up with several fitness apps. For example, I use GarminConnect and TrainingPeaks to capture all of my exercise data. The apps work seamlessly together so that I can see nutrition data in TrainingPeaks and exercise data (calories burned) in MyFitnessPal.
Since the first week, I have been at a steady state for body weight sticking right on 165 pounds. As I mentioned in my last post, I continue to feel very good physically and mentally. Other than a slight feeling of sluggishness early on in the diet, I have had absolutely no adverse effects from the nutrition plan.
Effects on Exercise
After spending the first four weeks of the ketogenic diet with unstructured exercise, I started a more formal base-building workout routine in week 5. I did a total of 11 hours of training with the longest session of 2 hours. I felt great during all workouts with lots of energy. But admittedly out of shape given my layoff from structured training.
I experimented with having a Bulletproof coffee (and nothing else) before a couple of my morning workouts including an easy two-hour bike ride. I only took on water and Base Salts during the ride. I never felt any real fatigue, loss of energy, or hunger. Pretty amazing!
Well, I’m officially sold on the ketogenic diet. After strictly cutting carbs and increasing fat consumption over the last 35+ days, I feel great. I’m encouraged with the results from my training so far. Once I found a routine of what and what not to eat, the transition has been pretty easy. I plan to stick with it for a while longer and continue to research how to manage the diet long-term.
I’m interested in feedback from others that have tried the ketogenic diet while endurance training and racing. Please leave a comment or email me directly at firstname.lastname@example.org.