Tired

Today I ran 13 miles, only half of what I'm training for and yet I was soooo tired. I ran the first 3 in 11 minutes and the rest were 12 minute miles. Ugh. That's not very fast. I guess training for the marathon should be tiring, considering that I'm trying to build muscles and endurance. In fact, if I really look at it, I wasn't as tired as I was when I ran my 1/2 in November, and I haven't run that far since then. So I should be really excited about it. But, I'm just too tired. :)