by Dave Asprey
WHEN THE WORKOUT’S OVER
Fast. Exercise. Eat. That’s the basic order of things as you are strengthening yourself. Which raises a big question: What should you eat after you exercise?
Your answer will depend on what you want your body to look like. Do you want to look like an ultralean, strung-out endurance athlete? A “swole” body builder? Maybe not that extreme. It’s better to find a comfortable middle: lean and muscular, not too much body fat, the picture of health. The look of health and longevity. I felt as though I had nailed it when the New York Times described me as “almost muscular.” Goals!
It’s all up to you, of course, but if I can make a suggestion, please avoid the starving animal look. This is the TV and movie version of what a fit person is supposed to look like. You know, the body aesthetic of Wolverine in the Marvel movies or of a woman who’s single-handedly battling a battalion of enemy soldiers. That physique actually comes from actors fasting for two days and taking diuretics to get rid of the water from the glycogen that their bodies have been holding on to. The ripped, lean, sexy style isn’t something you can actually sustain. It’s just a temporary thing that actors and fitness models do to get ready for a shirts-off scene.
I promise you that they don’t look like that all the time. It’s a short-term fix and really unhealthy. In fact, I’ll go further and say that it’s unhealthy even to fetishize that body type. Just as Big Food tries to get you craving foods that you don’t need and don’t want, Hollywood fantasies get you craving a physique that would literally kill you if you tried to maintain it. This is another great opportunity for you to exercise more self-control. Try going without the helpless desire for the kind of body that no normal human has. Do some squats, and grow a nice backside. Do some leg lifts and get quads. Just don’t expect to look like a superhero every day.
But I digress. Let’s say that you want to put on some muscle or at least maintain the muscle you have. As soon as you’re done lifting weights or doing HIIT intervals, you should eat. You can have some carbs as part of your postworkout meal. As I like to keep reminding you, it’s okay even to have a little bit of sugar on occasion—just not a lot, because sugar is bad for you. If you decide to have some starch, choose something such as rice, sweet potato, or root vegetables. Take advantage of the fact that bumping up your blood sugar will release insulin, which will then help you put on muscle. Unending keto can make it harder to put on muscle. Cycle your fasting, cycle your keto.
Carbohydrates will also boost your blood level of a separate hormone called insulin-like growth factor, or IGF, which signals the body to put on muscle. You want to strike a delicate balance here, though, because a chronically high level of IGF is associated with colorectal, breast, and prostate cancer. This is a place where the yin-yang between diet and exercise really helps you. Over a long period, intermittent fasting tends to drive down your level of IGF, protecting you from its potentially disastrous health effects. But in the short term you can hack your metabolism to boost your IGF level temporarily, so that you can bulk up and build strength.
If you’re not worried about being ketogenic and you want to put on muscle, you can also take an amino acid called L-glutamine. At the end of your fast—but only after you’ve exercised—take anywhere from 2 to 10 grams of L-glutamine. This flavorless powder will help you build muscle mass. It also supports a heathy gut lining and reportedly has a calming effect on your mood to boot.
Do you have to eat after an exercise session? Certainly not. If you’re looking to push your metabolic limits as an extreme athlete or just to prove how strong you are, go ahead and return to fasting. It will push you into ketosis faster and help you lose weight, but you’re going to feel pretty awful. But first you should make an honest assessment of your mental and physical state. Are you feeling strong? Confident? Directed? Or are you feeling overwhelmed? Remember that starting with an intermittent fast, exercising, and transitioning into a longer fast is very likely to raise your stress hormones. Having said that, if you’re not already overstressed (from work and family and the news cycle and all the random things we all have to deal with in our lives), and if you’re not sick, there’s no obstacle. You can go ahead and undertake the fast-exercise-fast challenge.
It is perfectly acceptable to do a multiday fast and keep exercising during the fast, but not until you have adapted to fasting and exercising on shorter fasts. It’s best to keep your workout basic. And don’t exercise right before bed—which is never a good idea, honestly, because it raises your adrenaline levels and can interfere with sleep. During a long-term fast, you should go for a twenty-minute or longer walk every day. Your daily walking break will increase your lymphatic circulation, the cycling of resources through your immune system. It needs a little kick while you’re giving your digestive system a break. Your body still needs to get rid of its toxins, even though you’re producing less of them in the gut. The walk will refresh your immune cells and do wonders for your mitochondrial biogenesis. It’s a simple, low-impact way to get stronger.
If you’ve reached the point where you feel truly powerful—rock solid in body and mind—you can go all-in on the attitude that you’re going to do something hard every day. I’m talking about heavy lifting while you are also doing a long-term fast. Like running a marathon, this is a pretty dumb idea, but if you want to show yourself how strong you are, it’s possible. There could be psychological benefits to feeling fully in control of your body. Just don’t make a habit of it.
Let me warn you: You’re going to really feel pretty darn tired. You’re going to be dragging. You’re going to be emotionally more reactive. You’re going to be a little bit cranky. You’re going to need a huge amount of sleep. Things that you would normally handle with no effort are going to feel bigger than they really are. The thing that sets you off might be a child whining, your boss telling you that you did a crappy job, someone cutting you off in traffic, or any one of a million other little things. Be prepared for them. Seemingly minor nuisances will loom large. You need to have the self-control to cut them back down to size.
If you are genuinely ready for the challenge, though, there are few feelings more exhilarating and life-affirming than pushing yourself harder than you’ve ever done before. Don’t even think about it before you’ve built up your strength. But if your mind-set is that you’re ready to show your body—and yourself—that you can do it, go right ahead.
You should do it because you want to do it, not because you feel you need to do it. This is certainly not something you want to do every time you fast, because it is incredibly depleting. If you must, try it once, and not more than once every few months. You can fast for multiple days every month if you want, and you can exercise lightly during those fasts.
However you choose to fast, however you exercise, and however you combine the two, keep your eye on the prize. What you’re doing is finding the strength inside you in all the different ways you can interpret those words.
7
Fast for Mental and Spiritual Health
The voice of hunger in my head couldn’t make me eat in the cave, so it tried to find other ways to undermine me. After all, nobody knows your weaknesses better than you do.
I was now a couple days into the vision quest, sinking into the solitude of First Woman cave and retreating deeper and deeper into my own mind. Or maybe I was exploring outward. My senses seemed to be growing sharper, more vivid, almost unbearably intense. I became aware that the stone walls forming the canyon were not just red but dozens of distinct colors I hadn’t noticed before. At one point I abruptly noticed that about a dozen sweat bees were with me in the cave. How had I possibly missed them before? I didn’t know if they were the kind that stung or not, but almost everything in the desert will sting you. They definitely derived a perverse pleasure from circling my head. They distracted me so much that I almost didn’t notice that I had way more energy than I’d expected.
At one point I left the cave and went for a long, slow hike
, testing out that welcome strength while also seeking respite from the hunger and loneliness. I carried with me a talisman of sorts, a dark gray windproof fleece jacket that bore the names and heights of the mountains I’d visited that year: Mount Shasta in California, Mount Cotopaxi in the Andes, Annapurna base camp, and Mount Kailash in the Himalayas. It had a few holes from errant campfire sparks, but it was what I always wore when exploring. I still do. I also had my hair cropped short, keeping the style I had adopted during my spiritual travels in Tibet, and a manly beard suitable for a vision quest.
It was remarkable how far away I felt from the moment of arrival at Delilah’s ranch. I laughed to myself, thinking back on it. She seemed unusual, for sure, but there was also something otherworldly about her. Every one of the few photos I had taken of her showed inexplicable orbs floating around her body. They looked like dust motes, but my lens was clean and they didn’t appear around anyone else. When I wiped my lens and complained about them, she just laughed and said, “You really think those are dust?” To this day, I don’t have a concrete explanation for what was showing up in those pictures, but Delilah demonstrated that she could cause more of them to appear on command before I snapped a new photo of her on my digital camera.
By the time I returned from the hike, though, my hunger had injected itself into my awareness again, and the water I drank to stay hydrated didn’t seem to help. At least my stomach had stopped rumbling. But my mind began fixating on food again as those bees circled threateningly. I lay down to sleep for the night, feeling increasingly anxious. I had two more days to go without food, and I was truly on my own until then. My brain started fixating on survival strategies. Should I try to call on my Boy Scout training? Maybe I could harvest some wild prickly pear cactus and cut it open with a knife. Do people ever eat it raw?
Intellectually, I knew I was fine, but the voice kept telling me that my life was in danger. That being without food was an emergency. That’s what hunger does to you when you don’t know what to expect. I had not yet crossed over to a state of self-control. In fact, as the now-familiar darkness closed in around me once again, I was feeling very much out of control. The voice in my head began whispering about predators, but this time even louder.
Much louder.
The voice grew so loud and insistent that I swore I could hear the desert sounds of a predator coming for me. I became totally convinced that I might wake up with a mountain lion raking his three-inch claws across the soft flesh of my belly. Except that in order to wake up to an attack, I would have to be able to fall asleep first, and that night it didn’t seem as though sleep would be coming to me.
WE ARE ALL SEEKERS
All of that fantasy and fear came from my brain.
We’ve talked about the ways that fasting can make your mitochondria stronger and your muscles stronger, reduce inflammation and extend longevity, help you sleep better, and even improve your sex life. We’ve talked, too, about enhancing the physical functioning of your brain, tuning its chemical balance and energy so you can think more clearly. These are all quantifiable, tangible changes. You can measure them scientifically. You can perform laboratory tests to confirm the release of specific hormones and ketones in the body that promote autophagy and improve your metabolic efficiency.
But you must also learn about the intangible aspects of fasting, because they are just as central to your well-being. In fact, they may be even more important, because they amount to the most basic reason for living. You could call it your soul. You could call it your inner consciousness. You could call it your chakras. Or your midi-chlorian-powered Force. Whatever terminology speaks to you, there is a deeply spiritual side to fasting. Many people would argue that all fasting has a spiritual dimension.
You might feel uncomfortable being asked to contemplate such a personal topic right smack in the middle of a book about intermittent fasting. Many people habitually keep their spiritual conversations separate from their conversations about the tangible world. For that matter, many people don’t consider themselves spiritual or religious and don’t necessarily see these things as important—or even serious. I get where you’re coming from, because that’s where I started out. Bear with me.
I come from a long line of sober-minded folks. My grandmother was a nuclear engineer. My grandfather was a physical chemist who wrote for the Encyclopaedia Britannica. The two of them met while working on nuclear engineering projects at the dawn of the Nuclear Age. I grew up indoctrinated in the idea that humans are nothing more than meat robots—that I am a meat robot. Life is just a biochemical process of power in, power out. Too much power goes in, that means you ate too much. Not enough power goes out, that means you didn’t exercise enough, therefore you get fat. Signals from your senses go into your brain, responses from your brain make your body move around and do things. Logic is all that matters. Anything that’s not logical is therefore garbage and should be ignored.
Over time, I came to realize that this purely materialist view of human biology couldn’t be true. Some of that revelation hit me while I was investigating various Native American traditions as a young man. A lot of it came later: in Tibet, in the cave in Arizona, in the jungles of the Andes, and in the process of getting married and starting a family. The whole point of spiritual practice, I see now, is that there’s a lot of stuff going on inside us that is clearly just not logical. Consciousness is not logical, and emotions are not logical. (The voices that tortured me in the cave were definitely not logical.) We are not flesh and blood. Or rather, we are not just flesh and blood; we are much, much more than that.
Fasting is one way to discover this complexity. There’s something inside you that is intimately tied to sensing and feeling rather than thinking. You intuitively know that hunger is a feeling, not a thought, and that feelings by definition are not rational. Some of the most powerful influences on your behavior aren’t rational, so there is no way that you can manage them in rational ways. The art of fasting is teaching yourself when those feelings are real and should be acted on and when they’re false cravings and impulses that are better put to rest. Fasting helps you gain the strength to act on only the feelings you choose to act on. It puts you into the driver’s seat, which sounds great until you remember the first time you got behind the wheel of a car and didn’t know where the brakes were.
Perhaps you still aren’t on board with all of this. I’m not here to proselytize, I’m just here to help you gain productive experiences and skills. Use the scientific method. Observe, look at the evidence, and decide for yourself. Wherever you stand on more ethereal matters, I guarantee that you will experience altered states when you become consciously aware of your body’s many unconscious behaviors around food. First you feel hunger, and then, before you really have a chance to think about it, there’s something else. A twinge. A resistance. Something holding you back. An old program, well hidden. It’s one thing to sit still and be alone or to meditate and become aware of your thoughts. What happens during fasting is that you become hyperaware of all your senses. Sometimes meditation and prayer are about stilling the mind, sensitizing you to feelings, not thoughts. Fasting does that, too, but it also helps you dial into your instincts at a bodily level so that you can get a handle on the feelings that tend to divert you from the path you want to follow.
The simple act of denying your body food can be a significantly more expansive spiritual act than meditation or solitude alone. If you use fasting to deepen your faith or expand your consciousness—or even if you just keep yourself open to these possibilities—you will achieve much better results than if you focus narrowly on goals of weight loss or longevity. When you approach fasting this way, there is also a wonderful humility to it. If you’re fasting for spiritual reasons, you probably won’t make a Facebook announcement about your fast. The goal of spiritual clarity and renewing your faith is completely at odds with the dopamine hit of receiving “likes.” You can make your fast a time of cleansing and transcendence that moves you beyo
nd the triviality of modern culture. Better yet, you can just make spiritual fasting a part of your modern culture. The point is, if you ignore spirituality, you are missing out on an entire world of experiences.
Remember the importance of moderation in all of this. You can work your body too hard, and you can work your soul too hard. You don’t want to get stuck in the group that says all fasting must be spiritual and you must put on a lily-white robe before you do it. There really are people like that. They missed out on the part about humility. Once you start running around in a robe, I’m not sure you’re still keeping yourself open to new experiences, either. But you also don’t want to get stuck in the group that refuses to keep an open mind and open eyes. As you are fasting, you may have a spiritual experience without intending to. Give yourself permission to make that journey, even if you don’t think of yourself as religious or as a seeker. If you begin fasting with the thought “I am skipping meals purely for the physical benefits” and you end up having a profound spiritual insight, that’s one hell of a bonus.
You can even regard your spiritual enlightenment as a purely scientific process, if you prefer. I’ve done meditation retreats in Nepal and Tibet and ayahuasca ceremonies in the Andes. Participants are always instructed to fast for a couple of days beforehand. Why? It’s not just because you’re going to throw up anyway from the exertion or altitude or fear—although that may be part of the reason. It’s because it’s what works, based on thousands of years of trial and error. Or it’s because fasting puts you into a state of increased clarity due to ketones and what they do to energize the neurons in your brain. If you argue that spiritual experiences are just about chemistry and electrons, you can frame it this way: deep concentration requires more electrical output from the neurons in your brain, and the neurons prefer ketones to glucose because of their greater energy density. Ketones have more electrons than glucose. More energy, more brain activity, more consciousness.