Why the Navy Seal 40% Rule is Key to Building Mental Toughness

It was my first Triathlon. I’d trained every day for the past six months and I was ready. The whistle blew and seconds later, I was in the water swimming.

About 200 meters out it happened: a cramp; so bad it felt as if someone had jammed a knife into my stomach. The pain was excruciating and I could barely move. As I watched the others swimmers pull away, I knew that I would have to quit and call for help. And then I remembered the 40% rule.

The 40% rule is a simple dictate used by the NAVY SEALS to build MENTAL TOUGHNESS: What it says is that ….

“When your mind is telling you that you’re done, that you’re exhausted, that you can’t possibly go any further, you’re actually at only 40% of your capacity.”

That’s when I realized that instead of giving up, I had to dig deep. And I did.

By the time I’d doggie-paddled my way out of the water, the shore was empty. Everyone else was on their bikes and well into the mountain course.

It didn’t matter. Even though the pain was intense, I was determined that not only was I going to finish, but that I was also not going to finish last. Two hours later I crossed the FINISH LINE, exhausted but ahead of the final three runners who I’d passed over the last hundred yards.

I’d completed my first Triathlon — but only because the 40% Rule had pushed me on …telling me that no matter what the challenge or difficulty, success is defined not only by our abilities but by our resilience.

At the heart of resilience is a belief in oneself.

Not the boasting, overarching confidence of an inflated ego but one grounded in a realistic assessment of the circumstances as well as the physical and mental abilities needed to cope with those circumstances.

Writing in Psychology Today, Harah Estroff Marano notes that:

“Resilient people do not let adversity define them. They find resilience by moving towards a goal beyond themselves, transcending pain and grief by perceiving bad times as a temporary state of affairs. It’s possible to strengthen your inner self and your belief in yourself, to define yourself as capable and competent. It’s possible to fortify your psyche. It’s possible to develop a sense of mastery.”

As everyone who has ever run a Marathon knows, the prospect of “hitting the wall” is never far removed. Hitting the Wall is defined as that moment in the race when continuing on toward the Finish Line seems exponentially harder that it did a few seconds before.

Not only does your body feel drained but your mind suddenly turns against you, whispering for you to stop, arguing that you’ve already proven yourself, that to keep running would be foolish, even dangerous.

And yet the percentage of runners who finish a Marathon is remarkably high, in many races such as the Boston Marathon as high as 98 percent.

Whether you call it grit or resilience or determination, the one thing common to every one of those runners is that at one point during the race they hit the wall yet continued on, digging deep into their core to find the strength to keep running.

It’s easy to be confident and push on when everything is going well. But as we all know, there are times when life hits you with a body slam that comes out of nowhere. You lose your job, get sick, or a parent dies and suddenly you’re put to the test.

How you respond will be in direct correlation with the mental toughness you’ve built up over the years. Or as the poet Charles Bukowski observed:

“What matters most is how well you walk through the fire.”

So, the next time you feel either frustrated or depressed or think that the odds are stacked against you and there’s not possible way for you to succeed …

Remember the 40% Rule and all the strength and resilience you still have left.