In the early 1950s, one sports barrier seemed completely unbreakable—running a mile in under four minutes.

Both the scientific and athletic communities had deemed it impossible. But on May 6th, 1954, Roger Bannister proved the world wrong, running a mile in 3 minutes 59.4 seconds, Bannister broke the four-minute mile, crushing a world record that had stood for nine years!

That’s a spectacular feat, of course, made possible by Bannister’s unwillingness to accept that it couldn’t be done. But even more stunning is what happened next. Less than two months later, a runner named John Landy also broke the “unbreakable” four-minute mile. In the following three years, a total of 16 runners did so, even shaving additional time off the record.

Had the human body changed? Nope. Had the track shrunk in size? Nope.  A mile was still a mile.

So what had changed? Runners now believed it was possible! Once Bannister shattered the record, it lost its power to deny the achievement. This limiting belief, this psychological barrier, had held others back for years. But one after another, runners began to believe.

The world record is currently 3 minutes, 43 seconds. Imagine that.

It’s amazing how real our mental barriers can be. So what barriers have you constructed in your life? What have you deemed as impossible? Imagine infinite possibility. Disallow psychological barriers. Normalize the impossible.

How can you break the four-minute mile in your life?