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Wednesday, February 16, 2011

Does A Marathon Run Compare To A Marathon Swim?

Courtesy of WOWSA, Huntington Beach, California.

In the Olympics, the marathon swim is 10 km. How can or does this accomplishment compare with the traditional marathon run of 42.195 km?

Stroke after stroke in the cold, rough water or step after step under the hot sun, which is harder? Which kind of marathon requires a greater effort? Which is a greater accomplishment?

For the elite athletes, the top male marathon runners finish in less than 2:10 while the top male marathon swimmers can swim 10K in under 1:55 under ideal conditions. The top female marathon runners finish 42 km in less than 2:25 while the top female marathon swimmers finish close to 2:00 - relatively close in time, but these elite athletes are not representative of the human population.

At the mass participation level, it is estimated that 1.8% of Americans can swim 500 meters non-stop. Of this 1.8% of the American population (approximately 5,526,118 people), it can be assumed that 420,000 individuals could swim 10 miles non-stop (approximately equal to the total number of registered USA Swimming + US Masters Swimming members + NCAA Division I, II and III athletes + junior/community college athletes).

If 10% of those 420,000 individuals are motivated to complete a 10 km swim, those 42,000 people equal about 0.013% of the American population. Because an estimated 467,000 individuals finished a certified marathon run in America in 2009, more people seem to be able (or motivated) to finish a marathon run than a marathon swim. However, this may be based on the fact that there are more opportunities to do a marathon run than a marathon swim.

What are your thoughts and opinions? Which is more difficult or a greater accomplishment - a marathon run or a marathon swim? This is something to consider while you are swimming 10 km in rough conditions against the current or running uphill under the hot sun.

Copyright © 2011 by World Open Water Swimming Association


  1. While both are hard I think swimming is more difficult. Conditions in OW vary more making it harder to finish. When running you can walk if you get tiered when your swimming sometimes you can't stop due to conditions or you won't make it to the finish. So runners have a better chance of finishing when fatigued due to the fact that they can walk to the finish.

  2. Comparing a marathon run to a marathon swim is probably alot like comparing apples and oranges. They're both so different. For me, I'd much rather swim 10K in rough conditions than run even a half marathon in those same conditions. Everyone is so different with various weakness/strengths you can't really compare running and swimming and say that one is tougher than the other. Even if the numbers show that there are much more marathon runners than swimmers.

  3. I would love to do a marathon swim and I could do it, but I would probably be in last place by quite a bit... because there would be so few others in the water. In my local town the longest open water swim is a 5K, and last year only 40 people swam it. I'm less likely to sign up because of the pure embarrassment factor of being 1/2 mile behind everyone at the finish (as all the safety kayakers patiently follow me in). A lot of "amateurs" run marathons and walk significant pieces and don't care if they take 6 hours to complete. Very few swimmers swim an open water unless they're really good/fast to begin with.

  4. Well, I have done a few marathon runs. 6 to be exact. And it's certainly tough. I'm a runner, not a swimmer, really. I've been doing Masters swim for the past 8 months and triathlon training with ocean swims for the past 2 triathlon seasons, and have swum in the ocean as far as 1.5 miles. Swimming 6 miles (10K) seems kind of scary to me. It would certainly be tough. I think contending with the open water conditions certainly throws something extra in there that runners don't really have to deal with. I love open water swimming, but 6 miles of swimming would probably take me 3-4 hours (my marathons take me almost 4 hours to run, so it's similar time-wise). Well, at this time the swim sounds tougher to me, but that's probably because I come from a running backrground. Someone who comes from a swimming background might feel the opposite.


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