Before Roger Bannister ran a 3:59 mile in 1954, the 4-minute mile was deemed impossible. After Bannister broke through that barrier, it was broken repeatedly by others. This was the running version of a “send train.” Once we know something is possible, there is a very real shift in our mindset, and we become energized to achieve what we once thought was too difficult. We see this phenomenon in climbing all the time. - Coach Matt Chapman