Around mile 10 of the Edmonton Marathon in August, Collin Jarvis was faced with a choice. One of the runners in the top pack pulled ahead at a pace that would lead to a sub-2:30 finish. Jarvis knew that he could either continue at a conservative effort with the group or risk hitting the dreaded wall while following the leader to a potential breakthrough. Just as he had done many times before in his life, Jarvis took the risk: He hung on to finish the race third overall, in a massive personal best of 2:27:30. Shaving 22 minutes off a...