The Top Reasons Ultrarunners DNF

This excerpt comes from Training Essentials for Ultrarunning by Jason Koop. In his book, Koop reveals the highly effective ultramarathon training methods he uses with elite ultrarunners and shows how you can use them, too.

While other endurance sports such as triathlon, marathoning, and cycling have an abundance of scientific research to draw upon, ultrarunning has very little. In the ultrarunning world only a few researchers (most notably Martin Hoffman and Guillaume Millet) have attempted to delve into the nuances of how ultramarathon runners work and what ultimately affects their performance. It’s a difficult proposition for a researcher. Finding subjects who are willing to run on a treadmill for the necessary durations is understandably challenging. And because of the remote nature of most ultras, fieldwork and race-day biological assessments are difficult to attain. Taking post-race measurements involves poking and prodding athletes who in many cases have just finished the most difficult race of their lives. With all these variables, the scope of what can be studied is somewhat limited.

Much of the research that has been conducted is based on pre- and postrace questionnaires. Why did you drop out of the race? What was your biggest issue? How many miles was your longest training run? While the answers to these questions offer a glimpse into a runner’s trials and tribulations during an ultramarathon, their usefulness is limited. They are the runner’s own interpretations of what happened, not necessarily clear explanations for why it happened. Take, for example, a commonly cited reason for underperformance in an ultramarathon: nausea. “I had a queasy stomach” and “I couldn’t tolerate any food” are certainly important sentiments to capture, but then what do you do about them? Very little research exists into why that nausea happened in the first place in an ultramarathon setting. Did you take in too much food? Not enough fluids? Too much of a particular carbohydrate? Is the gut actually damaged and leaking endotoxins into the bloodstream? Did your vision become altered late in a race, causing disequilibrium and nausea? We know that nausea is in fact an issue, but no one knows for sure what the key triggers for nausea are in an ultramarathon setting. Make no mistake: We’re getting closer and closer to finding helpful answers for this and many other questions. But you would be hard-pressed to find a singular “aha” discovery that would prevent nausea from happening in every case.

So what do we really know about the science of ultrarunning? In 2011, Martin Hoffman and Kevin Fogard published an article titled “Factors Related to Successful Completion of a 161-km Ultramarathon.” Their study explored the characteristics and issues that affected the performance of runners during the 2009 Western States 100-Mile Endurance Run and 2009 Vermont 100 Mile Endurance Run via pre- and post-race questionnaires. One of the more interesting tables in their article outlined the main problems self-reported by both finishers and nonfinishers (Table 4.1).

Through this lens, we can look at many of the failure points and limiting factors of performance and what the science has to say about them. Nausea, blisters, exhaustion, and muscle pain/cramping top the list of ailments runners mentioned as limiting their performance.

PROBLEM                            %

Nausea and/or vomiting    23.0
Unable to make cutoff times 18.7
Other, not categorized        12.2
Ongoing injury                     7.9
Injury during the race          7.2
Inadequately heat acclimatized       7.2
Blisters or “hot spots” on feet            5.8
Muscle cramping                                 5.0
Muscle pain                          4.3
Exhaustion                            3.6
Illness before the race        2.9
Vision problems                  0.7
Started out too fast              0.7
Inadequately trained         0.7

Surprisingly, in another part of Hoffman and Fogard’s study, being inadequately trained was the least cited reason (at 0.7 percent) for dropping out among nonfinishers  and represented only 13 to 15 percent of the complaints among both groups as a reason for limiting performance. For me, this data point is crucial.

I would argue that if you are nauseated, are unable to make the cutoff times, and have muscle pain that is forcing you to drop out or causing you significant issues, above all else, you are inadequately trained.

A successful training process for an ultramarathon addresses all those issues. Any ultramarathon will still be hard, and even the most well prepared ultramarathon runners encounter these issues, but training either alleviates or completely fixes these complaints. The striking fact is that while runners often are able to identify the acute causes of their discomfort, they usually do not correlate those sensations with being inadequately trained. This is important because it means runners are focusing on the symptoms and not the root cause of the problem: training.

Adapted from Training Essentials for Ultrarunning: How to Train Smarter, Race Faster, and Maximize Your Ultramarathon Performance by Jason Koop, coach to elite ultramarathoners. In his book, Koop reveals his highly effective ultramarathon training methods for ultrarunners of all abilities. Jason Koop is the Director of Coaching for CTS, coach to elite ultrarunners, and an accomplished ultramarathoner.