How can we define health? Ever tried to take a stab at it? I attempt to define “fitness” and “geek” here because they appear in the title. But it seems health is a mélange of a lot of things—genes, lifestyle, a feeling of being safe and in charge—not all of which we can put a finger on.

We tend to grope around in defining good nutrition and health. We can be too reductionist in our view of who’s healthy or whether we are healthy, claiming that “nutrition is 90 percent of health,” or that we have achieved some perfect biomarker like total cholesterol after six tests at the doctor’s office, so therefore we must be healthy. Or maybe we find out our telomeres are resilient and hanging in there, or we take a long survey on the Web, and the results pat us on the back and suggest we’ll live to be one hundred. Many of these things seem like feel-good, almost delusional exercises. So much about health is mysterious, yet to be discovered, and may never be discovered. I like that aspect of it, because it leads to more experimentation. Maybe your own ideas about how to stay healthy haven’t been refuted yet.

This doesn’t mean that you can’t aim for health, particularly if your current strategy has you waking up in the morning most days feeling pretty good. That’s where my “fitness” and “geek” definitions come in.

This is a book about fitness and nutrition for the independent of spirit and irrepressibly curious. The reason I have cleaved “nutrition” off from the general rubric of fitness is that, even though eating well (and the book will try to define that too) is part of being fit, we usually think of “fitness” as being an aspect of physical culture.

Fitness implies an underlying assumption of physical health. The Oxford American Dictionary defines fitness as “the condition of being physically fit and healthy.” This book will discuss fitness in respect to becoming a physically stronger person and aging as well as we can. It will not advocate achieving a level of fitness, say, for a particular sport that undermines health in the process, which can actually be pretty common among all our popular extreme sports.

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Mea culpa: I’ve done a few things in my life that some might consider extreme—like a five-hour–plus triathlon and a little mountaineering, mostly guided—but I would not claim that I was pursuing fitness during these adventures (I was fashioning unforgettable memories, and sometimes raising money for charity), and therein lies the difference. Since a good part of this book is about the latest and greatest gear that people are using for self tracking, speaking of extreme, I must pay homage here to the wonderful GoPro HD Hero helmet cams, which are tracking devices in their own right and have captured simply amazing outdoor videos for YouTube, such as that of a skier in the Alps being buried and dug out of an avalanche, and another skier launching off a cliff, unfurling a parachute, then watching an avalanche crash off the cliff behind him. Now that’s personal tracking.

METs Anyone?

I will attempt to define fitness in terms of energy output—this book mentions metabolic equivalent of task, or MET, a number of times. This is a simple numerical index of the energy a person outputs during the day. So, fitness is the ability to not only have the requisite energy to get through your daily tasks, but to be intermittently capable of a high-intensity energy effort: a higher than typical MET, like lifting a heavy weight, jumping high, or running fast, relative to your age and circumstances.

We might even aspire to a more brass-tacks definition of fitness, which also comes from Oxford-American: the biological angle, “an organism’s ability to survive and reproduce in a particular environment.” You want to aspire to a level of fitness that allows you to thrive in your environment and be reasonably free of serious chronic illness. In this book’s discussions of food, exercise, sleep, rest, meditation, hormesis, and other issues, I hope upon hope that readers can mine a few nuggets of information that help them “ a particular environment.”

The Food Angle

I like Boston Marathon winner Jack Fultz’s “see food” diet—“see food and eat it” (see Chapter 7 for an interview with him)—for its simplicity. Eating in the modern world is anything but simple these days. The act of eating has been completely medicalized, and has become sociopolitically militant to boot. The vegans are hurling pies (nondairy, of course) at the meat eaters, the vegetarians are aiming online flames at the omnivores, and the raw foodists are, well, refusing to cook anything.

As you’ll see in the chapter synopsis coming up, I’ll provide a lot of detailed nutrition information, but it all comes down to “eat real food.” Avoid processed junk and things we haven’t eaten for millions of years (OK, coffee might be one exception). Yes, especially in Chapter 1, I spend a fair amount of time with the ancestral-health meme, or paradigm, that has worked its way through Western culture and among science and nutrition circles during the last few years.

The Mashed-up Ancient Angle

Humans spent hundreds of thousands of years moving around a lot outside, sleeping fairly long hours by the solar clock, and eating lots of plants and animal foods—and we carry largely the same software code inside ourselves today (human genes) as humans did back then. The closest approximations to an ancient person now are contemporary hunter-gatherers like the Maasai or the Hadzabe in East Africa, and they tend not to get our diseases.

Maybe a good part of fitness is simply getting back to our roots—not corrupting our own internal software by immobilizing ourselves in chairs, in cars, or in front of screens, moving around under the sun (making vitamin D), taking the time to sleep, and eating real food. Maybe.

Ironically enough, this is also a book about the latest technology—apps and gear that uses Global Positioning Systems, 3D accelerometers, and data connections to your own web dashboards to track personal propulsion (in running shoes and ski boots, etc.), eating, rest, and sleep. So it’s a high-tech/ancient roots mashup. I certainly hope the mashup appeals and people don’t find it cognitively dissonant.

Annals of Experimentation

OK, now that we kind of know what fitness is, what’s a geek?

The typical image of a geek in popular culture is the Spielbergian hero with Coke-bottle glasses who gets picked on at school, then becomes the town hero when he hacks the computers at the nearby nuclear plant that’s having a meltdown. I tend to go for a broader definition, however. A geek is someone who spends a huge amount of time analyzing the fine points of whatever interests her, ad infinitum, to a level that no one around her can possibly understand. Her family members and friends are all flabbergasted and scratch their heads, until finally, with a shrug of their shoulders and a murmur of “fanatic...,” they return to quotidian concerns.

When a geek focuses on fitness, that interest often manifests itself as self-experimentation. Geeks are inveterate, fearless experimenters. They want to plunge into demonstrations and proofs of conventional truths and, to this end, subject their bodies to experiments that make others squeamish, like long fasts, “hormetic” cold-river swims, guzzling pans full of leftover beet juice and admiring the red color of their pee afterward, or sometimes just going out to a beach or mountain and sprinting like wild people.

They absolutely do not automatically accept the bland marching orders of some officially anointed expert, whether it be the company dietician, a health-network M.D. they’ve never seen before, or the acronym-denoted bureaucracy that is determined to lecture them about how to eat and exercise.

The several people I’ve interviewed in the book—including two NFL pro football players, a mountaineering guide, a national expert on vitamin C, a scientist who tests the effects of fasting on mice and tumors, an MIT scientist who studies our mTOR growth pathway, and a former Israeli soldier who studied the Spartans, Greeks, and Macedonians and made up a “warrior diet”—don’t necessarily fit any kind of cultural cross-section, but I think they’re all fitness geeks in their own right.

I know I’ve always been a fitness geek. I’ve kept a little text log of sleep, workouts, morning heart rate, and body composition since way before the Internet became popular. I’ve also been educated in English and American literature and software engineering, and have spent a fair amount of time as a software programming geek. I have found many parallels between software design and fitness geekdom, such as the whole concept of antipatterns, or learning how to do something by studying how not to do it first. These parallels are sprinkled throughout the book—as is a little code here and there, but you don’t have to be that kind of geek to enjoy the reading.

The “Measure First” Mantra

The final point I’ll make about fitness geeks is that measuring, whether it be with the Fitbit, Zeo, Endomondo, their own software, or a simple text file, is a big part of a fitness geek’s obsession (healthy obsession, I’d say). The other day, we got a mailing from the electric utility describing our home’s energy usage and comparing it to that of our neighbors. We’re usually right in the middle, leaning toward the most efficient and not the most gluttonous, but this time we had used way too much energy. I handed my 15-year-old daughter the graph of our energy usage and the local comparisons—“Here, you might find this interesting.”

Lo and behold, I started to find yellow sticky notes all over the house, at outlets and on appliances, containing tips on how we can reduce our electricity use. Cool! The old cliché is, “What gets measured gets managed.” The same is true with measuring health and fitness—the biofeedback makes a big difference.

How to Use This Book

This is a book that you can read from cover to cover, but you don’t have to approach it linearly. You can bop in and out of it—“Hey, today I’m going to read something about macronutrients or fasting.” Each chapter definitely stands on its own, so happy sampling.

This isn’t a book that prescribes exactly how to eat and exercise. “If you do A, B, C, and D, you will be healthy—trust me.” So many of those books come and go. I admire the determination and temerity of their authors to find the one pathway to Elysium. This book is, however, chock-full of ideas—mostly not mine originally, but certainly tested by me—of ways that you can tinker with your lifestyle and body and move into a different, healthy direction. I do appeal to some general paradigms, though, which I’ve mentioned—to eat real food, move around a lot, sleep copiously (things you’ve heard of before)—and I look at a lot of different tools that geeks have invented to help you measure and share your progress.

I suppose the pursuit of optimal fitness for yourself is a lofty goal, and it’s the path you take to get there that provides all the fun, stimulation, and gratification. In terms of pursuing personal, optimal health, it’s not selfish—let’s shake that monkey off our backs. It’s the fit person who has the energy and availability to be charitable, help others, and give more of herself.

Chapter 1

Too many of us are living in chairs (including the front seat of your Honda Civic or Ford Explorer), eating processed fake stuff on the run, and eschewing sleep for cable TV and social media. Isn’t our internal software designed for something—Monty Python enter here—completely different? Isn’t there a way we can live in the modern digital world and still feel physically vibrant? We look at cultivating respect for and seeking the wisdom of the ancients, as well as the evidence for rebooting our installed code and thus reacquainting ourselves with real food, sleep, and the great outdoors.

Chapter 2

There’s a lot of gear now that’s designed to promote fitness, as well as for just plain time-wasting fun. Self-tracking is a bona fide movement among humans. Want to track your exercise (even weightlifting), analyze your chow, and view your sleep graphs for the week? There are apps and widgets for that, and more. We look at stuff like the Fitbit, Endomondo, Fitocracy, Alpine Replay, Garmin Connect, Google Earth mashups, and, among others (Zeo is covered in Chapter 9).

Chapter 3: Macronutrients

This is the first of two heavyweight chapters on nutrition before we turn to the “kicking up your heels” part of existence later in the book. We explore everything you always wanted to know about carbs, fats, and proteins, and then some stuff you probably didn’t, like Rabbit Starvation Syndrome (the joy of living on seal fat) and the effect of fructose on your liver.

Chapter 4: Micronutrients

This chapter looks at everything you always wanted to know about vitamins, minerals, and phytochemicals, including some stuff that might have slipped past the school nurse during those vitamin lectures, such as “antinutrients” and what spinach might be doing to your mineral absorption, and the sorrows of vitamin deficiencies (and how easy it is to avoid them).

Chapter 5

Shouldn’t you just see food and eat it? Yeah, I suppose if you were wandering through a dystopian-blasted landscape with Terminators in pursuit, but these days we can be a little more nuanced about choosing food. As in, do your wandering through weekly farmer’s markets, find out what a CSA is, and get to know your local farmer (get to know him really well). This chapter also offers with some ideas for dealing with food shortages, price increases, and food deserts.

Chapter 6

This chapter also has a nutritional bend, but from a different angle—not eating for intermittent periods and the health benefits of fasting. We talk to a scientist that studies the metabolic effects of fasts, and we discuss numerous variations of fasting protocols and some of the stuff that happens with your body during fasting. We also interview the inventor of the “warrior diet,” which can involve eating for only four hours per day. Hey, the Spartans did it.

Chapter 7

This chapter looks at the absolute joy and necessity of being outside (we’re programmed for it), from the point of view of walking, sprinting, hiking, body-weight exercises, running, and skiing. You learn how to do Tabata sprints, a pull-up, and your own resistance-exercise regimen on a remote beach. We talk to a former Boston Marathon winner and a mountaineer. We bring in some of our favorite tools: Endomondo, Google Earth, and Alpine Replay. And hey, I’ll bet you never knew what friluftsliv was!

Chapter 8

You decide you gotta join the gym and get strong. Now what? We give you a rundown on the basics of resistance exercise in the gym (yeah, we figure you get the most bang for your buck by aiming to add and retain lean mass). The chapter talks about sets, reps, volume, and “repetition max,” then it jumps into descriptions of about 15 different techniques, including photos and links. We talk to two NFL pro football players about the not-so-casual aspects of getting strong enough to withstand a profession as modern gladiator.

Chapter 9

Ever written a random( ) method or function in your code? Did you know that randomizing fitness, as in letting an algorithm choose a random exercise for you, might be good for you? We propose a couple of ways that you could do that (the CrossFit world has a “workout of the day” tradition), including the tool. We also discuss an online tool for determining if an athlete is rested and ready to go, called RestWise. Last, but not least, is the all-important topic of sleep—and this is where you get a look at a nice piece of gear for the power sleepers of the analytic set: the Zeo Sleep Manager.

Chapter 10

Once you start going crazy on bumping up your outdoor and indoor activities, you have to start paying even more attention to nutrition. You suddenly start eating to get stronger and/or faster, not just because you’re hungry. This chapter discusses some of the nuances, such as eating more of everything to add muscle, the magic hour after exercise for chowing, as well as a few supplements you might consider based on the science literature. We interview an MIT scientist about the mTOR pathway, which is the core biochemical sequence, buried just about everywhere in your body, that controls growth of both good (muscle) and bad (tumor) stuff. That’s right, it’s anabolic.

Chapter 11

There are so many different potential ways that you can hack fitness (and at least delight in the experimentation, even if they don’t really work). This chapter discusses a few of them that probably do work, many falling under the rubric of hormesis, or good stress. Try cold-water swims, saunas, a nice glass of vintage grape (but not three), plus high-intensity exercise (also hormesis). “The world breaks everyone,” Hemingway wrote in A Farewell To Arms, “and afterward many are strong at the broken places.”


I always wanted to write a whole book about fitness, even before I became a geek (wait, I guess I always was a geek, they just didn’t have a word for it yet—curious dork?). I absolutely never would have published this book, however, without the help of numerous other people.

I’ll start with my family. My parents, Anne and Robert Perry, brought me up in Concord, Massachusetts (back then a land of rebels, geeks, writers, and readers), and constantly made sure that either I had a book in front of me or I was running around playing outside. No matter how hard he’d worked that day, my dad always took me outside to throw baseballs at him (note the suggestion of inaccuracy). Thereby a “fitness geek” was born. I’m grateful for everything they have done for me.

Stacy LeBaron, my wife, constantly lends her encouragement, not to mention indefatigable assistance, along with our two dear, fit children, Rachel (black belt in martial arts) and Scott (slick downhill skier in Vermont). It’s tough to carve out time to write a book, and these guys are constantly covering for me so I can escape to the Vermont woods to write, not to mention inspiring new ideas with their feedback.

I’m grateful to all the busy scientists, researchers, professors, athletes, inventors, and all-around fitness geeks who took the time out of busy schedules to answer my questions, after I had “cold emailed” them out of the blue. This would have been a far lesser book without their input.

I thank my editor Brian Sawyer, who shepherded the book along from the beginning, as well as the rest of the O’Reilly team and Bob Watson, Lindsay Peterson, and Meghan Johnson, the tech reviewers, whose feedback and perspicacious efforts have made this a better book.

I’d also like to acknowledge you, the reader, and your pursuit of health for health’s sake, which ends up benefitting everyone, not just yourself. Keep experimenting!

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