Another Few Barbells

ANOTHER FEW BARBELS

The book’s reception alerted me to another possible application of robustness in complex systems. The idea came from two fitness authors and practitioners who integrated the notions of randomness and Extremistan (though of the Gray Swan variety) into our understanding of human diet and exercise. Curiously, the first person, Art De Vany, is the same one who studied Extremistan in the movies (in Chapter 3). The second, Doug McGuff, is a physician. And both can talk about fitness, particularly Art, who, at seventy-two, looks like what a Greek god would like to look like at forty-two. Both were referring to the ideas of The Black Swan in their works and connecting to it; and I had no clue.

I then discovered to my great shame the following. I had spent my life thinking about randomness; I had written three books on dealing with randomness (one technical); I was prancing about as the expert in the subject of randomness from mathematics to psychology. And I had missed something central: living organisms (whether the human body or the economy) need variability and randomness. What’s more, they need the Extremistan type of variability, certain extreme stressors. Otherwise they become fragile. That, I completely missed.*

Organisms need, to use the metaphor of Marcus Aurelius, to turn obstacles into fuel—just as fire does.

Brainwashed by the cultural environment and by my education, I was under the illusion that steady exercise and steady nutrition were a good thing for one’s health. I did not realize that I was falling into evil rationalistic arguments, the Platonic projection of wishes into the world. Worse, I had been brainwashed though I had all the facts in my head.

From predator-prey models (the so-called Lotka-Volterra type of population dynamics), I knew that populations will experience Extremistan-style variability, hence predators will necessarily go through periods of feast and famine. That’s us, humans—we had to have been designed to experience extreme hunger and extreme abundance. So our food intake had to have been fractal. Not a single one of those promoting the “three meals a day,” “eat in moderation” idea has tested it empirically to see whether it is healthier than intermittent fasts followed by large feasts.†

But Near Eastern religions (Judaism, Islam, and Orthodox Christianity) knew it, of course—just as they knew the need for debt avoidance—and so they had fast days.

I also knew that the size of stones and trees was, up to a point, fractal (I even wrote about that in Chapter 16). Our ancestors mostly had to face very light stones to lift, mild stressors; once or twice a decade, they encountered the need to lift a huge stone. So where on earth does this idea of “steady” exercise come from? Nobody in the Pleistocene jogged for forty-two minutes three days a week, lifted weights every Tuesday and Friday with a bullying (but otherwise nice) personal trainer, and played tennis at eleven on Saturday mornings. Not hunters. We swung between extremes: we sprinted when chased or when chasing (once in a while in an extremely exerting way), and walked about aimlessly the rest of the time. Marathon running is a modern abomination (particularly when done without emotional stimuli).

This is another application of the barbell strategy: plenty of idleness, some high intensity. I took the research I read as support for combining long, very long walks with high-intensity exercise rather than just running.

I am not talking about “brisk walks” of the type you read about in the Health section of The New York Times. I mean walking without making any effort.

What’s more, consider the negative correlation between caloric expenditure and intake: we hunted in response to hunger; we did not eat breakfast to hunt, hunting accentuated our energy deficits.

If you deprive an organism of stressors, you affect its epigenetics and gene expression—some genes are up-regulated (or down-regulated) by contact with the environment. A person who does not face stressors will not survive should he encounter them. Just consider what happens to someone’s strength after he spends a year in bed, or someone who grows up in a sterile environment and then one day takes the Tokyo subway, where riders are squeezed like sardines.

Why am I using evolutionary arguments? Not because of the optimality of evolution, but entirely for epistemological reasons, how we should deal with a complex system with opaque causal links and complicated interactions. Mother Nature is not perfect, but has so far proven smarter than humans, certainly much smarter than biologists. So my approach is to combine evidence-based research (stripped of biological theory), with an a priori that Mother Nature has more authority than anyone.

After my “Aha!” flash, I embarked on an Extremistan barbell lifestyle under the guidance of Art De Vany: long, very long, slow, meditative (or conversational) walks in a stimulating urban setting, but with occasional (and random) very short sprints, during which I made myself angry imagining I was chasing the bankster Robert Rubin with a big stick, trying to catch him and bring him to human justice. I went to weight-lifting facilities in a random way for a completely stochastic workout—typically in hotels, when I was on the road. Like Gray Swan events, these were very, very rare, but highly consequential weight-lifting periods, after a day of semistarvation, leaving me completely exhausted. Then I would be totally sedentary for weeks and hang around cafés. Even the duration of the workouts remained random—but most often very short, less than fifteen minutes. I followed the path that minimized boredom, and remained very polite with gym employees who described my workouts as “erratic.” I put myself through thermal variability as well, exposed, on occasion, to extreme cold without a coat. Thanks to transcontinental travel and jet lag, I underwent periods of sleep deprivation followed by excessive rest. When I went to places with good restaurants, for instance Italy, I ate in quantities that would have impressed Fat Tony himself, then skipped meals for a while without suffering. Then, after two and a half years of this apparently “unhealthy” regimen, I saw significant changes in my own physique on every possible criterion—the absence of unnecessary adipose tissue, the blood pressure of a twenty-one-year-old, and so on. I also have a clearer, much more acute mind.

So the main idea is to trade duration for intensity—for a hedonic gain. Recall the reasoning I presented in Chapter 6 about hedonic effects. Just as people prefer large but sudden losses to small but regular ones, just as one becomes dulled to pain beyond a certain threshold, so unpleasant experiences, like working out without external stimuli (say in a gym), or spending time in New Jersey, need to be as concentrated and as intense as possible.

Another way to view the connection to the Black Swan idea is as follows. Classical thermodynamics produces Gaussian variations, while informational variations are from Extremistan. Let me explain. If you consider your diet and exercise as simple energy deficits and excesses, with a straight calorie-in, calorie-burned equation, you will fall into the trap of misspecifying the system into simple causal and mechanical links. Your food intake becomes the equivalent of filling up the tank of your new BMW. If, on the other hand, you look at food and exercise as activating metabolic signals, with potential metabolic cascades and nonlinearities from network effects, and with recursive links, then welcome to complexity, hence Extremistan. Both food and workouts provide your body with information about stressors in the environment. As I have been saying throughout, informational randomness is from Extremistan. Medicine fell into the trap of using simple thermodynamics, with the same physics envy, and the same mentality, and the same tools as economists did when they looked at the economy as a web of simple links.* And both humans and societies are complex systems.

These lifestyle ideas also drew on my reading of peer-reviewed research. I interpreted findings about episodic energy deficits, immune function, brain cells, cancer cells, and diabetes as support for the approach. That interpretation, together with changes I observed in myself, was the basis for my enthusiasm; my regimen did not isolate the effects of the individual practices. I felt I had re-created 90 percent of the benefits of the hunter-gatherer lifestyle with minimal effort, without compromising a modern lifestyle, in the aesthetics of an urban setting (I get extremely bored in nature and prefer walking around the Jewish quarter of Venice to spending time in Bora Bora).*

I extend the argument to economic life, claiming that eliminating speculative debt could lower 90 percent of Black Swan risks; the analogy alone does not establish that estimate.

The only thing currently missing from my life is panic, from, say, finding a gigantic snake in my library, or watching the economist Myron Scholes, armed to the teeth, walk into my bedroom in the middle of the night. I lack what the biologist Robert Sapolsky calls the beneficial aspect of acute stress, compared to the deleterious one of dull stress—another barbell, for no stress plus a little bit of extreme stress is vastly better than a little bit of stress (like mortgage worries) all the time.

Some have argued that my health benefits come from long walks, about ten to fifteen hours a week (though nobody has explained to me why they would count as workouts since I walk slowly), while others claim that they come from my few minutes of sprinting; I’ve had the same problem explaining the inseparability of the two extremes as I did explaining economic deviations. If you have acute stressors, then periods of rest, how can you separate the stressors from the recovery? Extremistan is characterized by both polar extremes, a high share of low impact, a low share of high impact. Consider that the presence of concentration, here energy expenditure, necessitates that a high number of observations do not contribute to anything except to the dilution. Just as the condition that makes market volatility explained by bursts (say one day in five years represents half the variance) requires that most other days remain exceedingly quiet. If one in a million authors makes half the sales, you need a lot of authors to sell no books.

This is the turkey trap: philistines (and Federal Reserve chairpersons) mistake periods of low volatility (caused by stabilization policies) for periods of low risk, not for switches into Extremistan.

Welcome to Gray Extremistan. Do not tamper too much with the complex system Mother Nature gave you: your body.