I’ve always considered myself to be in good shape. For years, I worked out and competed in CrossFit. If you’ve ever seen the CrossFit Games, you know it’s an intense sport requiring significant strength, typically broken up into shorter workouts. But when I embarked on my journey to climb mountains, I needed to improve my endurance and be able to perform at a high level for longer periods of time. After all, climbing a mountain takes days or weeks, not minutes or hours!
Training as a climber is a process, and I’ll address that in another post. But the research shows (and my own experience proves) that nutrition is at least half the battle. That’s why, when I got serious about reaching the Seven Summits, I also got serious about becoming a fat-adapted athlete.
What is a fat-adapted athlete?
Athletes who are fat-adapted burn fat for energy instead of glucose. The average person, when working out, burns glucose first. This is basically sugar derived from a number of foods, most specifically carbohydrates, and it runs out quickly.
Why should I become fat-adapted?
Athletes who choose to fat-adapt generally do so as a means to improve endurance and long-term performance. It’s popular among long-distance runners and mountain climbers – like me!
In addition to improved endurance levels, fat adaptation is particularly advantageous when climbing due in part to the lack of oxygen available at higher altitudes.
Looking at the numbers, fat contains 9 calories of energy per gram as compared to just 4 calories of energy per gram in carbohydrates. Just by its nature, fat is a denser source of energy, which allows the body to go longer. Additionally, the body can store significantly more fat than sugar, meaning it has more resources to draw from over long periods of time.
How do I become fat-adapted?
It’s a process, so make sure you’re in it for the long haul. Here are some basic steps to follow:
1. Reduce your carbohydrates. (And totally cut out refined sugar.)
This might take some time, depending on your current diet. You don’t want to shock your body too much by immediately and sharply cutting out carbs. And let’s be clear, you will have some sort of withdrawal period! But stick with it, because the less sugar you eat, the less your body will crave it.
When we talk about sugar, it’s important to note that this means any substance that the body will automatically convert to sugar, including many carbohydrates. Refined sugar is a modern-day creation, and it’s never necessary. Do yourself a favor even if you decide not to fully fat-adapt…cut the refined sugar altogether!
Your body does need some carbohydrates, but it’s not the kind found in bread. Carbohydrates are also found in things like broccoli and other vegetables. And that’s probably enough.
2. Increase your (good) fat intake.
Since you’re trying to get your body to burn fat for energy, it’s reasonable that you’ll need to increase the amount of fat in your system. Exactly how much fat you should consume depends on your needs and what you want your body to do. PaleoFX offers a good equation to figure out how many grams of fat you may need per day:
If you’re going for 80 percent of your calories from fat, this equation should help you identify a precise number of grams. Talk to your trainer, nutritionist or health care provider about how many total calories per day you need depending on your fitness goals.
3. Manage your intake of high-quality protein.
Eating a ketogenic diet in pursuit of fat-adaptation doesn’t mean eating ALL the protein you want. Part of the balance is ensuring you’re getting a moderate amount of protein and making sure it’s high-quality. Shoot for an intake equivalent to 0.7 times your lean body mass in grams of protein per day.
What should I eat?
Starting this diet is the hardest part, but once you’ve mastered it, the food is delicious! Here are some examples of what I eat to maintain my fat-adapted lifestyle.
Eggs (the yolks are the best part, but the whole egg is fine)
Bacon or sausage (be careful to avoid processed sausages with added sweeteners)
Low-carb dairy products (hard cheeses like Swiss, Greek yogurt)
Fatty fish (shoot for wild-caught things like salmon or tuna) – this helps accomplish both your fat and protein goals
Steak (fattier cuts, like ribeyes, are better)
Ground beef dishes (hamburgers sans the bun can be a great meal) – shoot for 85/15 fat ratios
Wild game (chicken, duck, quail, pheasant)
Low-carb vegetables (spinach, bell peppers, green beans, cabbage)
Salads drizzled with olive, avocado or other high-fat oils
Nuts – the fattier the better (almonds are excellent!)
Ultra-low training bars and drinks (My sponsor, SFuels, offers some truly delicious options without all the sugar of many “energy” drinks or bars. Use my code, SummitGoLonger, for a discount on your first order!)
Nut butters (stick to higher-fat versions like almond butter – avoid peanut butter)
How will I know when I’ve become fat-adapted?
Ultimately, you should test your endurance. You may still feel tired after an intense workout, but you should be physically able to continue for longer periods of time.
Another obvious sign of fat-adaptation is the ability to go longer between meals. Most people get “hangry” if they don’t eat often enough. But fat-adapted athletes may be able to go six or seven hours between meals and still feel OK, because their bodies are breaking down the denser fat in their diets at a slower pace.
Follow me on Instagram @tom_lawrence3 for more tips on eating as a fat-adapted athlete!