Ultramarathoner Dean Karnazes Is A Medically-Proven Super Human Who Can Literally Run Forever

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  • Dean Karnazes can run ultramarathons without stopping for hundreds of miles.
  • Karnazes has a rare genetic disorder that allows him to run pain-free.
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50 marathons, in 50 consecutive days, in all 50 states. While this may sound like a myth, it is a reality for ultramarathon runner Dean Karnazes.

Karnazes has a rare genetic disorder that allows him to run for hundreds of miles without stopping. He is a literal super human.

What Is An Ultramarathon?

Simply put, an ultramarathon is any race longer than the standard 26.2 mile marathon. There are two types of ultramarathons: those that cover a specific distance and those that last for a set amount of time. However, most are for a specific distance. For example, there is the 135-mile, non-stop Badwater race and the multi-day Self-Transcendence 3100 Mile Race.

Why Can Karnazes Run Forever?

Medically, Karnazes is an anomaly. During exercise, our body converts glucose to energy with lactic acid as a result. As this increases, we eventually reach our lactate threshold: the point where running becomes unpleasant, muscles begin to fatigue and cramping occurs.

But for Karnazes, his body never sends these signals. He has a special ability to flush out lactic acid as he is exercising.

“At a certain level of intensity, I do feel like I can go a long way without tiring,” he previously said to The Guardian. “No matter how hard I push, my muscles never seize up. What eventually happens is that I get sleepy. I’ve run through three nights without sleep and the third night of sleepless running was a bit psychotic.”


Not as a surprise, Karnazes has quite an impressive resume:

  • Completed 50 marathons in all 50 states in 50 consecutive days in 2006
  • Finished a marathon to the South Pole in −13 °F without snowshoes in 2002
  • Ran 350 miles in 80 hours and 44 minutes without sleep in 2005
  • Raced a 200-mile relay race solo, racing alongside teams of twelve, 10 times
  • Winner of the Badwater Ultramarathon, 135 miles across Death Valley, in 2003 and 2004
  • Ran 3,000 miles from Disneyland to New York City in 75 days, averaging 40 to 50 miles per day in 2011