Before the 4 minute mile was broken, it was considered humanly impossible. It was first achieved in 1954 by Roger Bannister in 3:59.4. The "four-minute barrier" has since been broken by many male athletes, and is now the standard of all male professional middle distance runners. In the last 50 years, the mile record has been lowered by almost 17 seconds. If we believe in achieving the impossible, we are much more likely to achieve it.