RULE 1: Make fat, not carbohydrate, your predominant fuel source for most outdoor activities and competition
The human body is able to use several different substrates as fuel sources during prolonged exercise. These range from ketones and fats, skeletal muscle and protein, to carbohydrates found in several different forms, as well as lactic acid.
The best analogy to the manner in which we metabolize these is the way we might burn soft wood or hardwood in our fireplace or wood stove. Carbohydrates are much like the soft woods pine, cedar, and fir. They tend to catch easily, are quick to burn, release quite a bit of heat, but are limited in duration. Anyone living in a Northern climate realizes at a young age that it is a mistake to try and heat a home with these types of wood. They are consumed so rapidly that, without a constant feeding, the fire will burn out leaving a house without heat or worse, with a chimney fire-heat/energy in the wrong place.
The same can be said for an athlete on a carbohydrate-based diet. The body prefers fat and ketones as a fuel, lactic acid is a second choice (if we train enough to be good at recycling it), and will use protein (by breaking down skeletal muscle) or carbohydrates (from glycogen) to complete our needs or if left with little else from diet. Numerous investigations with runners and cyclists, cross country skiers and rowers, among other athletes, have shown increased performance with higher fat, lower carbohydrate diets as well as with ketogenic diets that are very limited in their carbohydrate content. Most recently, the European Journal of Sports Science published a research paper that showed dramatic differences in performance with an adoption of a low carb, high fat diet in runners and cyclists(1). Athletes experienced significant decreases in their recorded times during trials and observed longer times to exhaustion or fatigue in comparison to previous diets or their peers who retained the typical high carb diet.
I have always though it best and saw the best results personally when climbing or hiking, trail running or paddling, on avocados, almond butter, coconut, and other high fat foods. In fact, I would estimate that I got more than half of my calories on every major mountain, Everest included, from olive oil.
It makes sense, even without a PhD in Sports Science or Nutritional Biochemistry. The mitochondria generate 99.9% of energy in exercise (life for that matter). The mitochondria can burn some fats in an extremely clean fashion (little in the way of undesirable intermediates or byproducts of combustion-the creosote if we return to the firewood analogy). These fats also give us more than twice the amount of energy per gram and, maybe most importantly for overall health, the right fats will provide us with low insulin levels (critical for optimal performance) and offer protection against the free radicals generated in exercise.
We need consistent energy available to our working muscles, it needs to be in good supply (everybody has fat to burn regardless of how lean they might be), and it has to burn cleanly so our mitochondria stay trouble-free and do not “catch on fire” with inflammation or oxidative stress-based pathologies like the wood stove or chimney that was stuffed with pine kindling and ignited on a cold winter night.
The best fats for exercise are the most stable. Saturated and monounsaturated fats are resistant to per oxidation or oxidative damage. The best sources can be found in both plants and animals depending upon availability and an athlete’s preferences. Included in the best of the best list are:
- avocados and anything you can make with them from guacamole to smoothies (see future blog listing best recipes)
- macadamia nuts
- almonds and almond butter
- grass-fed butter or ghee
- extra virgin olive oil
- extra virgin coconut oil or coconut butter
- and the yolks of pasture-raised eggs (the yolks are mostly fat and cholesterol-maybe the ultimate pre event or competition food)
Try to make your pre-training or pre-activity meal be high in one or more of these. Go slow at first, fat requires some additional digestive capacity and it may take a few weeks to get to where you can digest those 3 egg yolks in a breakfast along with a whole avocado and vegetables sautéed in coconut oil. When out in the mountains or on the water, develop trail foods around coconut and macadamia nuts which hold up really well in rough environments and pack an incredible amount of energy.
These days we make coconut macaroons with almost no sugar, bring canned sardines and goat cheese to have with carrots, and use as much grass-fed butter in almond butter bars for the trail. We also start out the day with our own version of Sherpa tea. I was always amazed at how this incredible mountain culture relied on Yak butter in tea to fuel a full day of climbing and carrying heavy loads at altitude. If it didn’t work, they wouldn’t be doing it. We add butter or coconut oil to our coffee or black tea, use full fat or heavy whipping cream at times, but try to avoid things like fruit juice or Gatorade in the morning as they can get the blood sugar roller coaster really going early.
In summary, start to experiment with egg and butter breakfasts (some vegetables added for more potassium and other electrolytes), avocado and lemon smoothies, or coconut-macadamia nut pancakes topped with berries and heavy cream or grass-fed butter in place of that granola and dried fruit combination, energy bars or boxed cereals. I am confident based upon both my personal experiences as well as the supporting research, that you will see great results in many areas of life, not just your success in the outdoors!