If fatigue was a fatal event, we would drop to the floor once we reached it. We would slow down and not be able to pick the pace back up, but that isn’t always the case. Each of us can recall times when reach the last part of a race, we find the energy to give a strong kick and run fast to the finish. The closer we get to the finish, our ability to push increases. Danger levels drop because we can clearly see the end in sight. The kick is a result of networking between anaerobic reserve, drive/reward, and a loosening of the safety mechanism from the brain. This phenomenon can be seen in studies that illustrate that at the end of a race, a larger amount of fatigue is permitted by the brain. Even though our fatigue increases, our brain lets us recruit a bit more muscle and endure more fatigue.
What is the kick made of?
A successful kick requires that we have a reserve left in our tank as well as psychological drive/reward. If we have these two elements, the reins are let loose a little more. The kick is largely based on our ability to tap into our anaerobic capacity. The trouble is that many runners use up their anaerobic abilities to maintain their pace during the race. When the time comes to kick, they may have the motivation, but they lack the anaerobic reserve.
The reason why we take months to train for a marathon is because our target pace is likely to be one that we can run, but we run it largely with great anaerobic effort, using up our limited glycogen stores and not tapping into the long-term energy source our fat provides. Training allows us to acclimate our bodies to the workload of that demanding pace, bringing an anaerobic effort down to an aerobic effort that serves as a much better system to use for endurance.
Train hard, train smart, and remember to save the best for last.
Be well and run on!