ok...so i am 22 and haven't run since High School. My times were about 4:02 and 8:25 and 5k was about 13:11. I mean, pretty average, but yea, i was good. So i went on a long run a month ago at like 9 minute pace and almost died. so on saturday, i entered into a 5k in chicago and ran it in 13:01. i dont understand it. i dont really train. i have good times. i ran an easy 10 today at 4:25 pace. im looking to run the chicago marathon in under 2:10 this october.