outta steam

i ran 5 miles today at 5pm.  i ran the first 4 miles at a 10 min. pace.  then bam.  i ran out of steam between 4 and 5 miles.  i was in the bright sun the whole time and was a total red sweat ball.  my legs were just d.o.n.e.  i kept running since i just wanted to get the hurry home.  then the light bulb went on that i had not eaten enough that day nor had enough carbs. a brilliant doh moment.  gotta love those!