If you believe the hypothesis that human beings evolved to run in order to use persistence hunting to obtain meat and protein that would ultimately increase brain size, then the question of why we began running seems fairly straightforward. But the question of why humans continue to run is more complex. Since running no longer serves a survival purpose, it is unclear why some, but not all of us, continue to run long distances today. What draws certain individuals to long-distance running? Is it nature? Do some of us run because our personalities predispose us to adopt and maintain endurance exercise? Or is it nurture? Does exposure to running shape us so that we develop personalities through running that facilitate our continued participation in the sport?
First, a caveat. There are myriad potential explanations for why only some of us become long-distance runners, and these can include genetics, social factors, family influence, and economic incentives. However, I’m focusing today on the role that personality plays in long-distance running. There are several studies looking at the personality traits of long-distance runners, many by assessing scores on the Cattell personality factor questionnaire. Raymond Cattell was a psychologist who theorized that these 16 pivotal source traits (shown at right; take the test here) explain variations in human personality. An early study of middle-aged long-distance runners indicated that runners “were significantly more intelligent, imaginative, reserved, self-sufficient, sober, shy, and forthright than the general population.” These conclusions are interesting, but don’t tell us whether these personality traits select for or are developed by years of running. To answer that question, we might look at young children who participate in endurance running, presumably because self-selected participation in running at a very young age might have more to do with nature than nurture. A study of 16 children, ages 4-12, who participated in extreme endurance exercise (running marathons and ultra marathons) showed that these young runners “shared distinct positive and negative personality characteristics.” For example, they scored high on boldness, warmth, self-discipline and sensitivity, but also on dominance, high drive with tension, and distorted body image. In fact, 2 of the 16 developed eating disorders, and a third committed suicide. Based on these data, we might conclude that there is some natural personality selection for long-distance running. And, at a young age, these personality characteristics may have both beneficial and detrimental impacts when fostered through many miles of running.
Another question that seems relevant to ask is what drives certain individuals to pursue high-volume, extreme endurance training over the course of a lifetime. If you watch the trailers to the documentaries of racers participating in the grueling Badwater 135 mile ultra marathon or Western States 100 mile ultra marathon, it becomes clear that these individuals are uniquely driven and/or shaped by their experiences. An analysis of participants in the TransEuropeFootRace Project, a 64-stage 4500 km (2790 mile) transcontinental ultra marathon, showed that runners were distinguished by three major characteristics: they had higher pain tolerance, were less reward dependent, and were more spiritually transcendent. It’s impossible to determine, though, whether these characteristics developed after a lifetime of training and running, or were always present and uniquely predisposed these runners to miles of solitary discipline.
The answer to the role of personality in long-distance running is unclear. It seems as though certain predetermined, psychological traits may make it easier and more seductive for some of us to run than others. But it is likely that the act of running itself develops or shapes personality across the lifespan, helping to support and modify traits such as intrinsic spirituality and self-discipline. Perhaps, then, the more important questions regarding endurance running that we should ask ourselves are: How did I get here? Why do I run? Where have I been, and where am I going?