It’s possible to hit the wall in a half marathon, and when you do it’s a special type of discomfort. You probably have a sizable chunk of road to cover, which gives you plenty of time for less-than-positive thoughts, like “why am I not better prepared?” It’s a frustrating question, especially if you put in the training time but still fade long before the finish line. If you’re wondering how to train better for your next 13.1-mile race so you don’t suffer through a similar fate, we spoke with run coaches who explain a few reasons runners tend to struggle toward the end of a half marathon, and what adjustments you can make to keep running fast, straight through the finish! Top Reasons Runners Fade in Half Marathons The dragging, “heavy leg” feeling you experience toward the end of a race is likely due to the build-up of metabolic waste and the micro-tears that occur in muscle fibers during exercise. You may also have drained your glycogen, or stored carbohydrates, which is your body’s preferred energy source.…