I'm halfway through my workout (over halfway through my run) and realized that I can run slower for longer. Seems obvious. The reason I can run 5Ks faster than longer distances is because I can push harder while doing a shorter distance. I don't yet have the endurance to push hard through a long run.
I think with half marathon training I need to focus on distance, rather than time, right now anyway. The time limit for the half is 3:30. I'm pretty sure that even at a slower pace I'll come in under that. Actually, I figured out an even slower pace on the treadmill (treadmill pace is already slower than my outdoor pace) and at that pace I'll finish in under three hours. My goal is to finish the half in under three hours... Even if it's 2:59:59 (although it should be less than that).
For now I'm slowing down on my longer runs, but only when needed. My goal is to finish a half and give myself a starting point for time. I need to focus on distance and being able to finish instead of speed during my long runs.
Okay back to my run... Had to post before I forgot.