TV Marathons--Such irony!

The irony of the name for an intense running race (26.2 miles, I believe) attatched to a couch potato (that's another story, the one of the potato farmers trying to get "couch potato" out of the dictionary and have it replaced with "couch slouch"; and a story for another day) causing anti-intellegence, possibly obesity-promoting, lazily unactive activity (the irony, to even call it an "activity") of a TV marathon is amazing. How did the name for an annihilatingly extreme distance race for ultra-runners (compared to me, at least) get pinned to a series of tv shows (a thouroughly unproductive activity, and I hope you'll agree)? I suppose because of the length, but I still consider it highly ironic that the name for an active race for healthy people can be the same as an "activity" that can cause inactiveness and health problems.