In 2013, Runner’s World published a piece by Amby Burfoot that concluded most runners are better off listening to their bodies versus following a formulaic pacing approach, according to a study he cites.
Amby reviews the marathon data and writes…
The runners held their pace for 13.1 miles, but then slowed dramatically. But wait. We all know The Wall doesn’t hit you until 20 miles. There’s no physiological reasons for marathoners to suddenly fatigue at the halfway point. What gives? Why did the runners crash at 13.1 miles?
My guess: The runners were relying too heavily on high goal-setting, heart-rate monitors, GPS systems, equivalent-performance tables, and the like. In other words, they used one or several of these tools to pick a goal pace faster than their actual race-day fitness. That’s what we high-success, high-determination, Type A runners often do.