"Five minutes each week that might change your life."

In 1980, Yiannis Kouros was a mediocre marathoner. Today, he is widely considered the greatest endurance athlete to ever live.

Kouros started by racing marathons. But after he’d finish a marathon, he’d notice something strange:

While his competitors collapsed on the pavement after crossing the finishing line, he felt like he had just gone on a Sunday stroll. He was ready to run another.

In 1983, Kouros signed up for his first ultramarathon—a 153-miler called the “Spartathlon.”

Without even trying, he broke the previous world record by multiple hours, finishing in 21 hours and 53 minutes. The next year, he broke his own record with a 20-hour, 25-minute finish—a record that still stands today.

Then, Kouros went on to run:

• 100 miles in 11 hours and 46 minutes
• 188 miles in a 24-hour span
• 294 miles in a 48-hour span
• 635 miles in a 6-day span
• 1,000 miles in just over 10 days

Scientists suspected his success was biological—that he had different muscle recovery from other people.

But Kouros insisted it was all mental.

“When other people get tired, they stop,” Kouros said. “I don't. I take over my body with my mind. I tell it that it's not tired, and it listens.”

Kouros is the gold standard of the psychological principle of self-efficacy—the belief that you’re capable of meeting a challenge.

As it turns out, simply believing you can do something dramatically increases the odds that you will. Research shows that when people think they can handle something, they’re more likely to persist, adapt, and succeed—even under extreme stress.

Every time you push through something, you build proof that you’re tougher than you think.

And over time, that evidence rewires your identity: “I’m the kind of person who does hard things.”

Run that proof long enough, then, like Kouros, you prove to yourself that anything is possible.

See you Monday,
Mark

P.S. You don't have to run a thousand miles to take over your body with your mind and make anything possible. Start with a book, or 15,000+.

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