Endure: Mind, Body, and the Curiously Elastic Limits of Human Performance

by Alex Hutchinson

In a wide variety of human activity, achievement is not possible without discomfort.

endurance is “the struggle to continue against a mounting desire to stop.”

What’s crucial is the need to override what your instincts are telling you to do (slow down, back off, give up), and the sense of elapsed time. Taking a punch without flinching requires self-control, but endurance implies something more sustained: holding your finger in the flame long enough to feel the heat; filling the unforgiving minute with sixty seconds’ worth of distance run.

Related experiments have extended this finding to clusters of related mental states: smiling, for instance, makes you happier, but it also enhances feelings of safety and—intriguingly—cognitive ease, a concept intimately tied to effort.

The self-talk group learned to use certain phrases early on (“feeling good!”) and others later in a race or workout (“push through this!”), and practiced using the phrases during training to figure out which ones felt most comfortable and effective. Sure enough, in the second cycling test, the self-talk group lasted 18 percent longer than the control group, and their rating of perceived exertion climbed more slowly throughout the test.

Just like a smile or frown, the words in your head have the power to influence the very feelings they’re supposed to reflect.

Over decades of follow-up, the children who resisted temptation the longest ended up with better test scores, more education, and lower body-mass index.

Kipchoge, whose English is fluent, is different. Though he’s so soft-spoken that you have to lean forward and squint to hear him, his words—and his demeanor, and the aura that David and I later agree he exudes—reveal a serene and imperturbable confidence. Is this what winning an Olympic gold medal does for you, I wonder? Or is it what you need to get there in the first place?

While great riders are often distinguished by the extremes of their physiology or their grace in the saddle, Voigt’s singular characteristic during an eighteen-year professional career was his appetite for suffering. His “open acknowledgment of pain as a state of mind to be combated, repressed and ultimately overcome,”

Such findings reinforce the idea that, all else being equal, the gold medal goes to whoever is willing to suffer a bit more than everyone else.

“Pain is more than one thing,” says Dr. Jeffrey Mogil, the head of the Pain Genetics Lab at McGill University. It’s a sensation, like vision or touch; it’s an emotion, like anger or sadness; and it’s also a “drive state” that compels action, like hunger. For athletes, the role of pain depends on how these different effects mingle together in their specific situation. Sometimes pain slows them to a halt; other times it drives them to even greater heights.

“It is reported,” he noted drily, “that pain can be strangely satisfying to the highly motivated athlete.”

This shows that simply getting fitter doesn’t magically increase your pain tolerance. How you get fit matters: you have to suffer.

“When I’m hurting like crazy,” he explains, “instead of blocking out the pain, I try to accept it, feel it as much as possible.”

While there are still plenty of gaps in the research, it does appear that top athletes really push themselves to a darker place, and stay there longer, than most people are willing to tolerate.

Salazar was famous for his unyielding racing style and his appetite for suffering. As a nineteen-year-old in 1978, he returned home to the Boston suburb of Wayland, Massachusetts, for the summer after a disappointing sixth-place finish at the NCAA championships ended his sophomore track season at the University of Oregon. He made a sign to post on his bedroom wall, scrawled in felt-tip pen on a giant piece of poster board, that he stared at daily: “You will never be broken again.”

The mind, in other words, frames the outer limits of what we believe is humanly possible.

trained ultra-runners have a higher pain tolerance than nonathletes, and even over the course of a single year the pain tolerance of athletes waxes and wanes with training cycles. In this sense, all training is brain training, even if it doesn’t specifically target the brain.

“Being boring is an important characteristic for inducing mental fatigue and, therefore, a brain training effect,”

I was a metronome, nailing each split to within a few seconds, with mental focus to spare.

Olympic athletes are strong and fit and tough. But none of that matters if they’re not also resilient, capable of shaking off setbacks and adapting quickly to unexpected circumstances.

when it comes down to two guys on a bike, maybe that’s the real secret weapon: believing that you have another gear.

Methodical planning and realistic goal-setting formed the bedrock of their coach-athlete relationship.

Telling runners they look relaxed makes them burn measurably less energy to sustain the same pace.

Even doing a good deed—or simply imagining yourself doing a good deed—can enhance your endurance by reinforcing your sense of agency: in one study, donating a dollar to charity enabled volunteers to hold up a five-pound weight for 20 percent longer than they otherwise could. Worryingly, they gained even more strength from imagining themselves doing an evil deed—confirmation, perhaps, of a theory, long discussed on online running message boards, that the best way to run an 800-meter race is fueled by “pure hate.”

the crew regularly did a workout of six times 500 meters as hard as possible. “And one afternoon, we did our sixth and turned around to row back to the boathouse, and the coach says, ‘No, go to the start again. You’re doing another one.’ So we did another 500. And he said go back. And we did another four. And you know, no one would have believed that we could do that, if you’d asked us.” That lesson, he recalled, stuck with him—first as an athlete and later as a scientist: “You have to teach athletes, somewhere in their careers, that they can do more than they think they can.”

The brain rules the body, Burfoot concluded, which is why his super-workout consisted of five times a mile as hard as possible, followed by your coach telling you to do another at the same pace. “From this workout, you’ll learn forever that you’re capable of much more than you think,” he wrote. “It’s the most powerful lesson you can possibly learn in running.”

confidence is great, but the marathon punishes overconfidence with Old Testament severity.

For athletes, the simplest way of acquiring justified true belief about your capabilities is to test them: whatever you’ve done before, you can do again plus a little more.

In any honest accounting, training is the cake and belief is the icing—but sometimes that thin smear of frosting makes all the difference.

If I could go back in time to alter the course of my own running career, after a decade of writing about the latest research in endurance training, the single biggest piece of advice I would give to my doubt-filled younger self would be to pursue motivational self-talk training—with diligence and no snickering.

When I line up for a race, I remind myself that my fiercest opponent will be my own brain’s well-meaning protective circuitry.

But it’s enough, for now, to know that when the moment of truth comes, science has confirmed what athletes have always intuited: that there’s more in there—if you’re willing to believe it.

Fighting all the way to the finish, he crosses the line in 2:00:25, pauses for the briefest of moments, and then jogs on toward his longtime coach, Patrick Sang, who wraps him in a silent embrace. Then, gingerly, he lowers himself to the ground, lies back, and covers his eyes. All around me, people are hugging, high-fiving, and screaming with raw emotion. While Kipchoge didn’t run sub-two, and thanks to the pacing arrangement didn’t set an official world record, I have no doubt that I’ve witnessed a watershed moment in the pursuit of human limits. Future marathon times will sound different in light of what just happened.

In the immediate aftermath of the race, though, the question that sticks in my mind is the opposite: How much faster could Kipchoge have gone if he’d had a rival with him in those final two laps? We know, after all, that racing against even virtual competition can boost performance by a percent or two compared to time-trialing against the clock. In a head-to-head race, could he have summoned the finishing kick that is nearly always seen in world-record runs?

“But you know, we are human.” It’s precisely that fact—his very human vulnerability—that has made Kipchoge’s run such gripping viewing for everyone who stayed up late or stumbled out of bed to watch it. And it’s what connects all of us, as we confront our own personal limits on the bike paths and mountain trails of the world, to those pushing back the limits of our species. Nothing is inevitable; nothing is simply mathematical. Kipchoge, I decide, has just come as close as anyone to truly touching the outer perimeters of his physical capacity. And that leaves me excited about the future—because, as he insists amid the good-natured post-race tumult on the racetrack in Monza, it was never just about him. “The world now,” he says, “is just twenty-five seconds away.”

The ultimate goal, it seems to me, is to dig deeper of your own volition—to be better than you were by leaving the tank a little emptier. That’s why, no matter what future research tells us about neat ideas like brain stimulation, the best answer I have for that nagging question about how to alter your limits is still humble, unsexy self-talk.

I can’t think of any place in the world I’d rather be than at a start line, either literal or metaphorical, balancing my eternal self-doubt with hard-won confidence and preparing to attempt the unknown.