How Do You Win a Marathon on a Torn Achilles?


Reflect: When to Quit and When to Grit

"Sometimes our behavioral inertia pulls us forward, toward continuing. Our thoughts latch onto a pursuit we've been after for years. We experience feelings of regret or remorse if we don't accomplish our goal. Our ego screams that we came this far, and we can't face our friends if we fail. The tough decision is to turn around, walk away, and quit… We often equate toughness with persistence, but in some cases, it's the exact opposite.
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Toughness is navigating the inner turmoil in order to make a good decision. Sometimes that's to persist. Other times it's to quit."

— Do Hard Things​

How Do You Win a Marathon on a Torn Achilles?

On Sunday, Tigst Assefa ran the third-fastest marathon in history, winning the Berlin Marathon in 2:11:04. But that doesn’t tell half of it.

With just over a mile to go, Assefa was ahead of world record pace, projected to run an astonishing 2:09:45. Then, she started to limp, significantly slowing but gutting it over the final mile and change to hang on for a new course record. Did she run out of fuel, hit the wall just before the finish line, pay the price of an early push?

Nope…she tore her Achilles tendon. For the last 1.4 miles, as her manager put it, “She was effectively running on one leg.”

Afterwards, her manager said her Achilles tendon was “completely gone…With a tendon like that, I don’t know how she could finish.” On Monday, she already had surgery.

It’s an absolutely insane level of toughness. One that will surely go up there in the history of athletes competing with injuries, and may even top that list. But it begs the question: how do you run over a mile on a torn tendon? Is that superhuman?

The science is fascinating. And it’s something I experienced firsthand.

The Weird Science of Pain

During World War II, anesthesiologist Henry Beecher studied 215 severely wounded soldiers. 32% said they felt no pain at all, while nearly three-quarters said they didn’t want any drugs for the pain. He concluded that “strong emotion can block pain.” While this was only an observational study, it set the stage for modern research that shows the meaning of an injury can influence its experience.

Neuroscientist Howard Fields proposed an explanation for this phenomenon: the motivation-decision model. Your brain weighs pain against everything else you want at that moment. When something bigger is at stake, it can turn pain down. It’s our nervous system dealing with competing demands and essentially deciding whether to value the pursuit of the thing or the retreat from the discomfort.

If you need to make it to the medic to help you and your squad survive...you don’t feel as much pain. Your body is prioritizing its signals, and it decides this one (pain) gets in the way of a much more important goal.

Think of a pilot in an emergency. Alarms flashing and buzzing everywhere. They all matter. But a good captain tunes out everything except what’s needed to steady the plane first. Our brain works similarly. We can turn up or down various signals, and even shift their interpretation.

One way in which this occurs is our brain’s natural pain relievers. In a 2013 study, researchers induced pain by restricting blood flow to their arm. Then they were asked to tolerate it as long as possible, with half the group being told the “ischemia would be beneficial to the muscles.” While the other were just told that it was essentially going to suck. The ones with the beneficial framing had increased pain tolerance.

Finally, they looked at what happened when blocking the body's pain-relief systems. Blocking either the opioid receptors or cannabinoid receptors partially blocked the advantage. When they blocked both, it eliminated the increase in tolerance. Their results can be seen in the title of the study, “Changing the meaning of pain from negative to positive co-activates opioid and cannabinoid systems.”

While we still have much to learn, I like to think of it as a kind of inner calculation. Your brain is making sense of your expectations, goals, pain, discomfort, likelihood of success, and all of the physiological and psychological signals bombarding it in those moments and then essentially deciding: is the juice worth the squeeze?

While much of the inner calculus runs in the background, we can influence it at a conscious level. One way is directing our focus. What we give attention to gains in value. So if we’re focused entirely on the pain, we often feel it more. When our attention is occupied with something else, research shows the brain turns pain down before the signal even reaches it, at the level of the spinal cord. If we refocus on the goal or catching the competitor ahead of us, our perception of pain decreases. We can also influence the calculus by setting the right expectations, adding context to how we interpret the pain, or elevating the goal’s importance. All of this shifts how our brain weighs whether continuing is worth it, and in turn, whether we should feel all of the discomfort and have it pull us towards stopping or slowing down, or not.

Our ability to modulate and shift how we experience discomfort is a powerful tool. But it’s also a dangerous one.

Now picture Assefa; she’s in the closing miles of the race. A new world record is in her sights. The thing she’s been targeting for months and years. The thing that will put her at the top of the running mountain, netting her millions of dollars, and much more.

She feels the Achilles, a little at first, then more and more. But the pull of the finish is too strong. She almost assuredly still felt the pain, as we can see her limping along the final stretch. But that finish line, and her lifetime of learning how to deal with high levels of discomfort, was enough to keep her going despite the serious injury.

I’ve experienced this firsthand on a much smaller scale.

In 2014, I raced a half-marathon as my tune-up to attempt an Olympic Trials qualifier in the Marathon. With about a mile to go, my Achilles screamed for just a minute. It felt like I stepped wrong, and I could feel it all. But I was in the middle of a race, with only a mile to go, and actively going back and forth with a pro runner for the win. My competitive instincts took over; I closed out the last mile in 4:30 and took the victory.

But then I was out for months because I partially tore my Achilles. I missed the ultimate goal of qualifying for the trials for a meaningless victory.

I still felt the pain during the race, but if you asked me during or even after the race, I would have told you, “Oh, just bad tendinitis.” My brain had edited the signal.

So is it toughness? Yes. It still hurt a lot. As I’m sure it did with Assefa. But toughness is more than handling discomfort. It’s navigating it: asking whether the risk is worth the reward, without being blinded by the goal.

Too often we think of toughness as just doggedness and persistence. But I see it another way; it’s a decision-making process. It’s taking wise action, which means being able to have just enough space to see if the persistence is serving the long-term goal. That’s why, sometimes the tough decision is to quit.

In my case, I should have stopped immediately. It was a meaningless tune-up race. For Assefa, maybe winning Berlin was worth it? She ran the 3rd fastest time in history, took home a major victory and a nice payday, and almost held on for a world record. I probably would have made the same choice to push on in that case. Though time will tell the impact of her injury.

But that’s the point. Toughness is nuanced. The same brain that let her run on one leg is the one that can blind you.

You can see this most clearly in studying climbers who try to summit Everest or similar mountains. Researchers found climbers sometimes get so locked in on the summit that they don’t take into consideration whether they have the resources and energy to make it all the way down. It’s “Summit fever.” A blindness to the goal that makes you tune out everything else. Or as the researchers put it, an “escalation of commitment and difficulty stopping.”

That’s why real toughness is so hard to figure out. We’re always pulled, sometimes to slow down, other times to press on. And both can be the right answer, depending on the circumstances. Toughness is a decision-making process, knowing how to weigh all the competing signals and make a choice that you can live with, that aligns with your values and what you care about deeply.

If the goal is big enough, your brain will let you push through almost anything. That’s the gift and the danger.

Toughness is knowing which finish line is worth it.

-- Steve Magness​


More Good Stuff:

  • A hockey player at Arizona State is in a coma after a "military-style" toughen-em-up workout. Can we stop this nonsense? Can we stop using poorly designed workouts whose sole purpose is to make people suffer? Steve argues that his entire sport is about going to the well, and that we need to understand the nuance of fatigue, instead of blindly pushing folks to it.
  • Brad lists out 33 'quests' to help you break out of a rut this month in his most recent Substack ​

Listen: How to Have More Agency

"You can just do things" — but should you? The word "agency" has exploded in recent months, but what does it actually mean to be a high-agency person, and when does agency cross the line into recklessness? Today on "excellence, actually," we're tracing the concept from Aristotle to Nietzsche to Silicon Valley, exploring why agency is core to our humanity in an age of increasing automation. We unpack the tension between people who overthink and never act versus those who act without thinking, share stories of taking big swings (including 25 book rejections), and offer practical tools for building agency as a muscle — whether you need to take more action, or you need to learn to pause and reflect before just doing things.

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The Growth Equation

Weekly ideas about living a good, meaningful and high performing life in a chaotic world from Brad Stulberg and Steve Magness. Best selling authors of PEAK PERFORMANCE, DO HARD THINGS, and THE PRACTICE OF GROUNDEDNESS.

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