We are excited to have Christopher Kelly join us as a guest writer on our blog. We asked Christopher some questions about metabolic efficiency and energy sources for endurance athletes. He’s written a great article in response…this is part 1 of 2. We would love to hear your experiences and questions so feel free to comment below.
How To Become A Fat-Burning Machine (And Why You Should)
by Christopher Kelly
It’s 60 minutes into your training. You’re getting lightheaded, dizzy. Good thing you brought those gel packs. Reaching for that sugar-laden gut bomb, you squeeze the oozing gel into your mouth. Sickeningly sweet. But, you get a rush of glucose. You’re able to finish your training, but there’s got to be a better way to fuel. You know it’s not healthy. Just because you’re an endurance athlete, are you doomed to investing in a lifelong supply of Energy Gels?
No matter how long you’ve been training and fueling your races on carbohydrates, you can still shift from being a sugar-burner to becoming a fat-burning machine. Here’s what you can do about it. It’s simple in theory, but it does take time to adapt. You’re an endurance athlete: nothing is as hard as spending your weekends on long rides, runs or swims, not even changing your fuel source.
- What is metabolic efficiency?
Efficiency is the amount of energy produced by a given amount of oxygen and food consumed. Being metabolically efficient means that you are able to easily convert the food you eat and the air you breathe into energy via the Citric Acid Cycle (CAC). This cycle does require several micronutrients to make the conversion from food and oxygen into usable energy (ATP):
The list of micronutrient dependant steps in the CAC are:
- Vitamins B1, B2, B3
- Lipoate (Alpha Lipoic Acid)
When everything is working well, your energy in equals your energy out. You always have the energy you need from the food you just consumed (the fed state), or energy that you have stored (fasted state). This allows you to get in a good workout, handle stress at work and manage matters at home. The problem arises when one or more of these micronutrients are missing. This disrupts the flow of energy, just like an accident on a busy expressway. Even though one or two cars are the only ones involved in the accident, they disrupt the flow of traffic for thousands of other cars on the same highway. A urine sample collected at home for organic acids analysis makes it possible to measure the flow of traffic and therefore, metabolic efficiency.
Where do these micronutrients come from? Some can be synthesized internally, but a majority of them must come from your food. Nutrient density is the key to becoming metabolically efficient and having the ability to generate more energy. It’s also the key to becoming fat-adapted. When you begin to consume a variety of nutrient-dense fats in your diets from sources like grass-fed beef and lamb, pastured pork, salmon, you are giving your body the micronutrients it needs to become metabolically efficient.
- Why is becoming fat-adapted advantageous for the everyday person and for endurance athletes?
Becoming fat-adapted makes you bonk-proof! The average person has the following energy storage capacity:
- 120g of glycogen in the liver (~480 kCal)
- 350g of glycogen in the muscles (~1,400 kCal)
- 11,800g of fat in adipose tissue (~100,000 kCal)
Picture a gas tanker, the type that delivers gas to a gas station. The tanker has a small tank that it uses like any other vehicle, and in theory it could run out just like any other vehicle. The irony is the large tank containing the payload for the gas station could still be full. In this analogy, the gas in the small tank that fuels the tanker is glycogen, the storage form of glucose (sugar). The large payload tank is fat stored in adipose tissue. Becoming fat-adapted then is like modifying the gas tanker so that it can use all of the fuel on board. The range of the vehicle is almost without limits.
As the name suggests, hormone-sensitive lipase is an enzyme whose function is inhibited by the hormone insulin. In order to get access to the fat stored in adipose tissue, insulin must be kept low. Your body releases insulin in response to consuming sugar. What’s the first thing that everybody does before starting a race? Shut down fat-burning by consuming a sugary gel! As anyone who has tried to consume more than 400 kCal of sugar per hour will tell you, there’s a hard upper limit on what your body can absorb.
Glycolytic pathways (that convert glucose into energy) produce more reactive oxygen species (ROS) than beta-oxidation (converting fat into energy). ROS are unstable molecules looking for another from which to steal an electron and so become stable. If the electron donated comes from the membrane that forms some part of a cell, then that cell could become dysfunctional and may even die. ROS are unavoidable and in some ways essential, but in excess cause harm. Simply stated, if you rely heavily on excessive carbs for fuel, you could be missing out on the benefits of fat adaptation, like anti-aging, steady energy and stable blood sugar levels.
When sugar is used as fuel, you will notice that your blood sugar levels tend to fluctuate, rather than remaining steady after meals. Have you ever felt a surge of energy after eating a high carbohydrate meal or felt sluggish after eating a heaping plate of carbs? Have you ever felt dizzy during the day? Or hungry enough to eat the person next to you? That’s low blood sugar. We assume that these symptoms of low blood sugar are normal, but they don’t need to be your normal.
After eating a meal comprised of nutrient-dense meat, fat and vegetables, you should feel a steady flow of energy. This is a result of fat adaptation. No, it doesn’t mean you will never eat starchy carbs again, but it does mean you are not reliant on carbs to feel energized. I do typically recommend eating a serving of starchy vegetables or carbs with your evening meal when the small glycogen tanks are more likely to be empty.
Fat should be your primary fuel source—not sugar—because fat gives you a steadier supply of energy. When your cells can produce energy with something other than glucose at the time of low blood sugar, you never have symptoms.
- Why is it important to continue consuming quality carbohydrate sources for endurance athletes while working on becoming fat-adapted?
Transitioning to a fat-adapted state is stressful to your body, similar to when you overreach in your training to become a better athlete. Your body is comprised of trillions of cells, and when those cells suddenly have their main source of energy removed—sugar—you’re going to experience symptoms. You wouldn’t attempt a marathon or a century ride straight off the couch, nor should you attempt to ditch all carbohydrates.
You can ease the transition by first removing the refined carbohydrates, like sugar, from your diet outside of training. Added sugar is everywhere, hidden in almost every bar, drink or snack inside a package. You’ll need to become a label reader if you want to continue eating packaged foods, but the easiest way to make the switch is to just eat real food! A good starting point if you are new to the process is the Whole30 plan, as it provides you with a variety of nourishing foods to choose from without feeling deprived of your old favorite munchies or sweet treats.
Once you get rid of all the refined carbohydrates in your diet, you can start experimenting with other protocols based on your level of training, your goals, your current health status and your lab results. This is also a great time to see a functional medicine practitioner, who can help you tailor your program.
Still unsure how you to move forward with all the blood sugar issues because you’ve already tried low carb? Ready to take action on becoming fat-adapted today? Let me help you. Book a free appointment, and we’ll find the reason why you are struggling to become fat-adapted. You’ll soon be able to train better, have more energy and feel steadily fueled during the day without needing to reach for that gel pack at minute 60.
Christopher Kelly is a computer scientist, pro mountain biker, certified Functional Diagnostic Nutrition Practitioner and graduate of the Kalish Institute. His wife is a food scientist, and together with Dr. Jamie Busch they run the functional medicine practice Nourish Balance Thrive.
Nourish Balance Thrive offers to athletes a holistic system that integrates the latest in modern scientific testing with age-old natural health solutions for weight loss, fatigue, depression, digestive problems and hormone imbalances. Through the implementation of simple lifestyle changes and the use of individualized, lab-based supplement programs, you will achieve your unique solution for optimal health.
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