The 40% Rule: A Navy SEAL’s Secret to Mental Toughness

Achieve mental toughness – Use this (scientifically) proven mental framework to push yourself beyond your limits.

99% of people who start a marathon finish. It’s a surprising number, I know, but there’s a reason that it’s so high. It’s called the 40% Rule, a concept used by Navy SEALs to increase mental toughness.

Navy Seal Mental Toughness

In his latest video on Big Think, Marquis Jet founder Jesse Itzler tells the story of the time he ran a 100-mile race alongside a 260-pound Navy SEAL:

“I first met “SEAL” at a 100-mile run in San Diego and I was running this race as part of a six-person relay team with friends and he was running the entire race by himself,” Itzler said.

“Who is this guy? I’ve never seen anything like it. And during the race, I kept an eye on him and around mile 70 — he weighed probably 260 pounds, which is quite large for an ultra runner — he had broken all the small bones in both of his feet and had kidney damage and he finished the race.”

The 40% rule

“He would say that when your mind is telling you you’re done, you’re really only 40 percent done. And he had a motto: If it doesn’t suck we don’t do it. And that was his way of forcing us to get uncomfortable to figure out what our baseline was and what our comfort level was and just turning it upside-down.”

The 40% rule, the SEAL explained, is the reason why even though most people hit a wall at mile 16 during a marathon, they’re still able to finish.

You can watch Itzler’s entire video below. It’s worth the six minutes, I promise.


Is the 40% rule real?

The story of Itzler and the SEAL sounds amazing, but does the 40% rule actually have science behind it, or is it just some motivational seminar nonsense? Science says yes, it’s legit.

In a 2008 study, researchers found that subjects who were given a placebo but told it was caffeine were able to lift significantly more weight than those who were really given caffeine.

Of course, this doesn’t imply that our bodies and minds are limitless, but it does confirm that the extent of those limits needs revising. Often we limit our abilities, but Itzler’s story and hundreds like it prove that we’re capable of exceeding these limits.

Like running a marathon every day of the week or memorizing a deck of cards in 20 seconds – turns out that what we often think is impossible is really just the 40% rule in place.

Push yourself past your limits this week!


Your compare list