
This is the last of three articles introducing an in-depth series on the topic of pacing marathons. This article continues a description of my coaching background, starting in 1979 as a rookie professional coach and marathon program director.
In the early years, most of my athletes wanted to compete and perform in the marathon, so I purchased a computer in the early 1990s and began crunching numbers to understand the factors that hinder or enhance performance in the 42K marathon.
My first study led me to promulgate a 4.2% rule: that athletes who did the first 10K segment of the marathon 4.2 percent slower than their average race pace finished with the fastest time they could muster on the day, and without a crashing slowdown on the final race segment from 30K to 42K.
By contrast, those who ran a faster first 10K segment had a much greater risk of crashing in the last 12K segment, while not performing as well as they could have. As the training grew into the mid-2000s, I found that a significant number of athletes weren’t necessarily concerned with a fast finish time. They were running the first 10K much slower than 4.2% of their average goal pace because they enjoyed flying by others on the last 12K segment more than hanging on for a fastest possible finish time.
Thus, my athletes forced me to recognize five mathematical ways they could perform on the final segment: flying (2% or more faster than average race pace), cruising (within 2% of average race pace), hanging (2 to 6% slower), slowing 6 to 10% slower), and crashing (more than 10% slower than average race pace). With this all-encompassing scheme in mind, I was on the cusp of a 10-year inquiry into the way pacing affects race experience (fun or not fun) and performance (fast or slow).
“My athletes were my study cohort, and the numbers were revealing in areas I chose to investigate.”
In my favor were large numbers of athletes in my marathon training programs—typically well over 100 who finished the marathon between 2009 and 2018. My athletes were my study cohort, and the numbers were revealing in areas I chose to investigate. As I reported earlier, I determined that the cause of crashing was the way my athletes paced the marathon, rather than conventional explanations, such as their training or marathon ability. As a result, I changed the way we approached the race in 2010.
First, I required everyone to have a pacing plan, which I gave them using a specially developed pacing spreadsheet. They told me their goal pace, and I gave them a written, mile-by-mile pacing plan. Second, with a few exceptions, I required them to race in groups with others who had the same pacing plan. As a result, we brought the incidence of slowing and crashing down to 33% in 2010. That was still too high for me. Looking carefully at our 2010 results, I saw that they were going slow enough on the first 10K, but they were disregarding their plans by running too fast during the next 21K.
With that in mind, I got them to follow their plans through 30K during the 2011 marathon, and they brought their incidence of slowing/crashing down to 14%, from 48% in 2009. Thereafter, 15% became the gold standard for marathon program performance.