Written by Bruce R. Copeland on November 16, 2008
Ultrarunners often get asked the question “How can you run that far?” For several years now there has been a provocative scientific hypothesis which says distance running was a significant part of human evolution. According to that hypothesis [D. M. Bramble and D. E. Lieberman, “Endurance running and the evolution of Homo.” Nature, vol. 432, pp. 345-352, 18 Nov. 2004], such well-known human traits as lack of body hair, high perspiration rate, upright stature, high arches, broad shoulders, and large gluteus maximus were selected through evolution to make it easier for us to run long distances.
As a long distance runner, I naturally find this hypothesis quite attractive. However if we’re going to embrace such a hypothesis, I think it makes sense to broaden it a bit. Humans in fact evolved (and evolved running) in at least half a dozen distinct geographic/climatic regions. Moreover different human populations apparently ran for different reasons. Taking this into account would go a long way toward explaining the wide diversity in electrolyte needs, in ability to tolerate heat/cold while running, in nutritional needs/strategies, in muscle physiology (fast twitch vs. slow twitch, etc.) and in human anatomy/body type.
Perhaps someday we can expect to undergo a few simple genetic tests that will tell us which electrolyte combinations we need, what foods we should eat on the run, and which distance we’re best suited for: 26.2 mile, 50K, 50 mile, 100 mile, or… Whether this would truly be an improvement, I don’t know.
But the next time someone asks you that universal question: “How can you run that far?” the appropriate answer is “We were all born to run long.”