Peak Nutrition. Maria Hines
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the protocol: http://shepherdworks.com.au. For a super-nerdy take on digestion, watch this video by Precision Nutrition: www.precisionnutrition.com/how-digestion-and-absorption-works.
FOOD INTOLERANCES
If you think you might have irritable bowel syndrome or a sensitive stomach and you have dealt with the life stressors that could be causing these issues, you may have food intolerances. Food intolerances could be a result of either an enzyme in the body that can help break down a particular food or an immune response if the body perceives the food as a threat. Common food intolerances include dairy, yeast, gluten, nuts, shellfish, soy, legumes, fructose, and sugar. Food intolerances are very common; most people have had some sort of bad reaction to food, some more often than others. To make matters worse, each person has a unique reaction to food, which makes solving the problem more complicated.
The first step is to eliminate foods that cause you inflammation or pain. Start this protocol by keeping a more detailed food journal that includes timing of food and when you get symptoms of irritability. When you see a correlation, consider taking that food out of your diet and seeing what happens. This process does take a while to figure out, but it’s worth it. And removing something from your diet doesn’t mean you can’t ever eat it again—it just means you are armed with more knowledge and can prepare for the worst. If you eliminate foods and increase your use of probiotics (and possibly greens), your gut may repair itself to the point that you can reintroduce certain foods back into your diet. Of course, not every gut is going to respond to probiotics and greens. You may have to figure out more intense protocols, such as eliminating all sugar or undergoing fecal implantations (this is where you receive stool transplants from a donor with a healthy gut biome to restore gut flora).
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HOW FUEL PROVIDES ENERGY
HERE IS WHERE SOME OF YOU MAY NOD off. The content in this chapter is a bit nerdy. Feel free to skip ahead to get the main points. You learned in chapter 5 that once nutrients are digested and absorbed, they are shuttled through the liver for a final screening, then sent to general circulation throughout the body to reach cells that need them. At this point, nutrients could be used for energy production; sent to tissues in the body to be used for specific functions such as the brain, muscles, and adipose tissue; stored for future energy needs; or eliminated from the body.
Now it’s time to get down to the body’s energy currency—adenosine triphosphate (ATP)—and the energy systems responsible for fueling your favorite mountain sports. If you understand how fuel provides energy for your body, you will have an easier time figuring out your own peak nutrition plan and when to eat carbohydrates, proteins, and fats. This chapter explains energy transfer, micronutrients and macronutrients, insulin and blood sugar levels, and the science behind hydration.
ADENOSINE TRIPHOSPHATE (ATP)
To achieve peak nutrition, mountain athletes need to fuel their bodies with the appropriate amount of nutrients to create enough ATP, the body’s energy currency. This essential molecule carries the energy for every baseline process in the body, including the continuous muscle contractions that take place on those long slogs up to the summit. You need a constant stream of ATP to keep you moving and to keep pushing you toward your objectives. The more ATP you have, the more you can do. The kind of outdoor sports you do will determine how you spend the currency.
One of the essential laws of thermodynamics that pertain to mountain athletes is this: energy is never really created and it’s never really destroyed. Instead, energy is transferred from one entity to another. In a nutshell, the energy in the food you eat is converted into a usable form for the mountains you climb, as well as for the baseline energy needs of your body. If you take a closer look at the macronutrients in food, you’ll see that they are made up of organic molecules, with many carbon-hydrogen bonds. When these bonds break, you get a burst of energy that is used to fuel the process by which ATP is formed from ADP (adenosine diphosphate) and P (phosphate).
ATP use is triggered by nerve communication as you are about to contract a muscle. Although it can come from new nutrients, most of the ATP in your body comes from stored nutrients, so the food you ate yesterday or the day before will be used for today’s energy needs. The exception is long endurance activities, such as multipitch trad climbing, backcountry skiing, and big wall climbing, which require a lot more energy, so during these activities foods you consume at that moment will also be used for energy, in addition to stored energy. Otherwise, during most activities—including short-duration exercise (such as bouldering and lifting)—the energy you need comes from long-term stored nutrients in the liver cells, the muscle cells, and the fat cells. For these reasons, if you want to perform well in the future, it is important to have optimal nutrition quality and good daily eating habits.
The two most important stored nutrients that provide energy for ATP production are glycogen (carbs) and triglycerides (fats). When these nutrients are broken down into simpler forms, they generate enough energy to bind ADP + P into ATP and to act locally in the tissues where they are stored. These nutrients provide energy for cells that don’t have energy stores of their own, such as the brain and red blood cells. In times of low food intake (during fasting, extreme dieting, or very long endurance endeavors), they will continue to circulate through the body to provide cells with enough energy to generate ATP. This process is essential for survival.
Your body breaks down larger molecules into a more usable form:
Glycogen
Triglycerides
Proteins
ATP 101
To recap: You need a constant stream of ATP to carry out both your most basic and higher-level functions. The energy that is needed to generate more ATP comes from triglycerides and glycogen. It’s the breaking of the phosphate bonds in ATP that releases the energy for the task at hand—for example, muscle contractions and enzyme production. Once this bond is broken, it leaves us with ADP + P again, and the body will repeat the cycle of breaking carbon-hydrogen bonds to regenerate ATP.
ENERGY TRANSFER AND ENERGY SYSTEMS
Your body needs ATP, but how much do you already have in your body, and how does the process of creating more ATP work? Even though ATP is crucial, the body has only enough stored to perform a few seconds of maximal exercise.
For any maximal effort lasting longer than that, the body must regenerate ATP. There are a few systems in the body that can do this, each creating ATP at different rates and some kicking in depending on whether oxygen is available to the system or not. The three systems the body uses to transfer energy and regenerate ATP are:
•The ATP-PCr system (anaerobic)
•The glycolytic pathway (anaerobic)
•The oxidative phosphorylative pathway (aerobic)