running a marathon 

to leave a group of people at random times to masturbate, then come back out of breath and play it off like nothing happened

John: "yo tom! where you at?"
5 minutes later
Tom: " sorry man i was running a marathon"

running a marathon by South Wick September 7, 2010

running a marathon 

When you become extreamly intoxicated off of captin morgan and passes out in someones trailer. Then that person is awoken by his friends 3 hours later and goes snowboarding. This is know as Running a Marathon

"i wanna run a marathon" said bones

running a marathon by beef April 17, 2005