Endure: Mind, Body, and the Curiously Elastic Limits of Human Performance Paperback – February 16, 2021

This is one of the most fascinating books I have read in recent memory. Hutchinson, writing in a style reminiscent of Malcolm Gladwell (who actually wrote the book's foreword) or Freakonomics investigates how the human body works and how it can be pushed to its limits - or beyond what we often perceive as our limits. The book was initially inspired by the chase to run a marathon in under two hours - a conquest many believe to be beyond the limits of human capability. The record has since been broken, but only in a very controlled and optimized setting, leaving questions remaining, but opening the door for the possibility much wider than previously considered. This is one of many principles Hutchinson looks at to bridge where psychology and physiology interrelate to define our limits. Once something is proven to be possible, it suddenly becomes attainable to a far wider audience; this is one of the clear psychological barriers. While the book does not definitively conclude how much is mind vs how much is body in defining limits, it clearly uncovers that the mind plays a much larger role than we like to give credit. Hutchinson references, and indeed observes, many ingenious studies aimed to identify what the true physiological limits are - from explorers in wild conditions, to elite athletes, to living and dead animals having their muscles stimulated by electrical currents. One of the central pillars is that the human body has many self-regulatory systems that act as a governor to keep us from approaching anywhere near our actual limit. As one of many examples, he considers the limits of oxygen deprivation. By looking at ultra free divers, a familiar pattern emerges that they must psychologically manage. Holding one's breath for an extended time begins with discomfort, a signal to the brain that oxygen is needed. If one continues to avoid breathing, the diaphragm will begin to spasm to try to force a breath. If one continues to refrain the task actually becomes easier for a time and a second wave occurs allowing the extension of holding one's breath. This is because the spleen sequesters a cache of oxygenated blood to be released in case of emergency. The true limit is far beyond what most people consider because few will willingly push themselves to the point of the spleen anticipating death and offering a final boost (clearly, this is not something a normal person should strive for). There are obviously much more pedestrian examples like how, if racers are running all out in an olympic race, is it possible that most are able to increase their pace in the last stages of the race? Or why, if access to glycogen stores is critically important, do most top marathoners allow their glycogen stores to deplete over the course of the race rather than keep them topped up? Or, more psychologically, it has been revealed that rinsing one's mouth with carbohydrate rich solution and spitting it out has a nearly identical impact on performance to actually drinking it (the suspicion here is that there is an as-yet unidentified pathway from the mouth that signals to the brain carbohydrates are coming, allowing an override of the governor that would otherwise signal you to reduce your effort). There are dozens of studies, real world examples, and fascinating stories, backed up by the biology and chemistry of how it works, that reveal so much about how our bodies work in the everyday and in the extreme limits of exertion. All of it is remarkably digestible and written almost like a series of mysteries to resolve. Simply put: this is a brilliant, enlightening, and entertaining book that will teach you about the limits of that which we're capable and why, even if it doesn't necessarily provide all of the answers.

An excellent text, delving on the extreme outer limits of human endurance. You will learn a lot about how far we can be pushed but I doubt that you would (or should) attempt what is described in this book. So this is more for encyclopedic knowledge than for practical application by an endurance athlete like the vast majority of us.

This book is a must read for endurance athletes at any level (even those just thinking about starting). The stories of elite athletes and outstanding attempts & accomplishments are inspiring and sometimes cautionary. Importantly, there are actionable items for anyone looking to enhance their performance. Maybe you need to think about your hydration or fuel or thinking to meet your next goal. It’s all in there. Great book! I hope he updates it regularly.

Easy to understand and appreciate the vast amount of effort complied by so many dedicated people.

The breadth of coverage is incredible: time spans from seconds to months; distances from zero or hundreds of yards to entire continents, and ranges of volitional control from nearly total (breath holding) to largely passive (surviving extreme altitude without supplemental oxygen).Part of what holds this extreme diversity together is the notion, introduced by Tim Noakes, of a "Central Governor," a self-defense mechanism that keeps us from harming ourselves. Some of the success of top athletes might be linked to an ability to ignore the urging to slow down and instead to keep going at full speed.The very long duration examples of endurance, such as pulling a sled across Antarctica, or an alpine-style month-long mountain ascent, are interesting as extremes but are obviously very different from a hundred meter dash, a marathon, or even a multi-day run. It's not so obvious that there's a "Central Governor" at work when the limits of survival are exceeded. Also one wonders what happened to the central governor while reading news stories of high school football players collapsing and sometimes dying during or soon after practice from heat stroke or overuse of muscles (rhabdomyolysis and compartment syndrome).The text is filled both with details of lab experiments and with stories of individuals pushing the known limits. Special attention is given to the two hour marathon along with other "barriers" which have been crossed, such as the four minute mile.The book as a whole is a handy compilation, made up in part from the author's web posts at OutsideOnline. It's great to have so much information in one handy package.