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First things first—what does it mean to negative split a run?
Well, my friends, my official/unofficial definition is this: to negative split a run means that your splits per mile progressively get faster. A perfect negative split run is when each mile is faster than the last. Most runners still consider the run to be a negative split if you start slower and finish faster, even if there is a mile or two in the middle where your pace is slightly positive.
For years I didn’t listen to music on runs outside. In order to keep myself entertained, I would find various different things to work on during each run. One of the tactics I practiced was a fast finish. This means I sprinted the last half mile of the run, pretending that it’s the finish line of a race. I also learned to negative split by noticing how I felt during every mile. I would increase my effort slightly as each mile progressed.
The key to running a negative split is to start the first mile slow or even painfully slow.
Official/unofficial definition of painfully slow: a pace that you feel silly running at because you tell yourself in your head, “I might as well be walking because this feels too easy.” Remember that your painfully slow pace will vary from day to day depending on how you feel, the weather conditions, and the terrain.
After a slow start, work on increasing the effort slightly with each mile. When you get to the end of the run, two things will happen. You will thank me for suggesting the “painfully slow” start. If your first miles are too quick, you would have to hit an uncomfortable and unrealistic pace that you have never run before during the last miles. And because you started out slowly, you will be able to run faster than you thought possible that day.
When learning how to negative split, don’t pay attention to your watch. Don’t look down obsessively at your arm to see if you are running a pace that is faster or slower than the last mile. Practice increasing your effort gradually by feel. If you increase your effort too greatly from mile to mile, you won’t be able to keep running at a sustainable pace. This technique teaches you patience, which is an essential part of marathon training and racing.
Why is it good to learn how to negative split a run?
The majority of runners believe that in order to run a PR pace in the marathon, you have to start slower and finish faster. This technique works in other distances as well but is often the most apparent in the marathon, where many people are accustomed to hitting the wall. The wall can be avoided—YES I just said that! The wall does NOT have to happen in a marathon. There are, of course, other factors that can determine how effectively you execute your marathon, but in my opinion as a coach, controlling your pace at the start is one of the most important.