Mind, body and the limits of human performance: A review of ‘Endure’
As cyclists, we understand limits. We know what it’s like to ride so hard that it’s not possible to go any harder. To have legs, lungs and heart screaming at us to stop. We know what it’s like to hit the wall on a long, hard ride in the hills; to feel that there’s nothing more to give.
But what are these limits exactly? Where do they come from? What’s stopping you from riding harder or longer? From breaking that personal best you’ve been unable to crack for years?
That’s the subject of the latest book by Alex Hutchinson, called “Endure: Mind, Body and the Curiously Elastic Limits of Human Performance”. It’s a book that was nine years in the making and one that has plenty to teach us about athletic ability, endurance, and how we can get the best out of ourselves.
Hutchinson sets the scene with the story of “Breaking2”, Nike’s somewhat infamous quest to break the mythical two-hour barrier for the marathon. It’s a story that Hutchinson has weaved throughout the book and one that exemplifies what he’s trying to achieve with “Endure”: to investigate the limits of human performance and whether (and how) it might be possible to get past them.
Hutchinson takes the reader on a guided tour through the history of endurance research, introducing key concepts (e.g. VO2max, lactate threshold and carbohydrate loading), key researchers (e.g. Tim Noakes, Samuele Marcora and Ross Tucker), and showing how our understanding of the limits of human endurance has evolved over the years.
And Hutchinson is the perfect tour guide – he’s a science PhD, a great writer, and also an elite distance runner in his own right. He synthesises and presents complex research in a clear and compelling way but he also knows what it’s like to suffer, to push yourself to your limits, and to want to push past those limits.
The book is peppered with stories from Hutchinson’s years as a runner, helping to illustrate the concepts he explains. These anecdotes are an important ingredient — there’s a very real sense that the author doesn’t just understand the concepts he’s presenting, he’s lived them too.
One of the key recurring themes throughout “Endure” is the question of whether an individual’s physical limits are set by their body or their brain. It’s a complex and fraught topic — indeed, as Hutchinson writes “The brain’s role in endurance is, perhaps, the single most controversial topic in sports science.”
Say you’re out for a long, hard ride and you get to the point where you simply can’t go any further. Is that your body reaching the limit of what it’s capable of? Or is it your brain deciding that it’s time to stop, and instructing your body accordingly? Putting it another way, does your brain set physical limits, as a way of protecting your body? And if your brain does impose those limits, is it possible to muffle or ignore your brain’s instructions, allowing you to push further and unlock potential you didn’t know you had?
A compelling example of this comes with Hutchinson’s discussion of freediving and the inescapable human need for oxygen. As he writes “The urge to breathe … turns out to be a warning signal that you can choose to ignore — up to a point.”
This, too, is a key theme of the book: that some of the things we understand to be limits are more fluid than we might expect. But, crucially, there is a limit. At some point, the freediver will need air, just as the ultra-endurance cyclist will need food and water if they’re going to keep riding hundreds of kilometres a day for weeks on end.
There are some enjoyably surprising moments in this book. For example, Hutchinson’s description of research showing that swishing carbohydrate drink around your mouth then spitting it out can offer a performance boost. Why? Because, seemingly, “the brain relaxes its safety margin when it knows (or is tricked into believing) that more fuel is on the way.”
Or the research that suggests mental fatigue has a real effect on athletic performance. Or that when you’re reaching exhaustion while riding, your brain seems to know it’s happening before your legs actually give out. “Shortly before the cyclists gave up,” Hutchinson wrote of participants in a German study, “there was an increase in communication between the insular cortex, which was monitoring their internal condition, and the motor cortex, which issued the final commands to the leg muscles.”
Cycling features prominently in “Endure”. A chapter on pain opens with an ode to Jens Voigt’s tenacity and the genesis of his famous (if by-now slightly tired) catchphrase “Shut up legs!” The hour record gets several pages, with Voigt, Eddy Merckx and Bradley Wiggins getting a mention, while Tom Simpson’s death on Mont Ventoux is discussed in a chapter about heat. Many cycling-related studies are referenced as well, including those on the power of self-talk, the importance of hydration, and the value of high-fat-low-carb diets.
And while “Endure” certainly isn’t all about cycling, that won’t matter to the vast majority of cyclists. It’s a compelling read full of great stories about the athletes and adventurers who have helped evolve our understanding of what humans are capable of. To name just a few: Roger Bannister with his legendary sub-four-minute mile; Reinhold Messner and Peter Habeler with their world-first ascent of Mt. Everest without supplemental oxygen; and perhaps most strikingly, Mexican prospector Pablo Valencia who managed to survive for a week in the desert without water.
Quite simply, “Endure” is a worthwhile read for any athlete that’s ever pushed themselves, or wondered where the limits of their endurance might lie. As Hutchinson notes, it “isn’t a training manual” — it’s not a step-by-step guide to ignoring your body’s warnings and pushing beyond what you thought was capable.
What it is is a thoroughly researched, well-written book that will give you an appreciation for what’s happening in your body and your brain when things start to get tough during exercise. It will inform, entertain and likely inspire you to learn more about what you’re capable of, and what “capable of” even means.