Homer Simpson may not be much of an athlete, but he and his family are running one heck of an ultramarathon for FXX.

In Day 1 of the longest programming marathon in TV history, 34 reruns of old episodes of "The Simpsons" shattered ratings records Thursday for the cable network started last year.

During prime time, the animated classic delivered a fivefold increase in FXX's ratings, with just over 1 million total viewers, according to Nielsen.

"We knew that 'The Simpsons' could be transformative for FXX and its performance yesterday truly exceeded our wildest expectations," FXX president of program strategy Chuck Saftler wrote in a statement.

FXX obtained the syndicated rights to "The Simpsons" and is running every episode -- all 552 of them so far -- in a 12-day marathon.

What do you think of "The Simpsons" marathon?

Twitter: @scottcollinsLAT