Martin Strell, a Slovenian has likely broken his own long distance swim record by swimming down the Amazon River from Peru to Belem in Brazil, approximately 3,300 miles in nine weeks, about 50 miles a day. That is approximately the same distance as across America.
I have to ask myself when I hear these kinds of stories, what on earth motivates these kinds of adventurers to go through extreme discomfort including chafing from the wet suit, sun burn, diaharrea..(you can read it all in the link) and worry about piranhas, flesh eating fish and sharks.
I have the same concerns for mountaineers who face death, frostbite, exhaustion...to go higher than anyone else.
Boring as it is, I think I will just stick to my day job.