I ran my first marathon last October, and ran it at a pace that would not make me feel awful. I finished it in 4:24. I ran my first half marathon yesterday, at 1:54. My quads seemed to get really tired around mile 10, but otherwise I felt good. After the race, I seemed to recover very quickly, so I feel I should have been able to run it faster. What can I do to help with my quads, since that is the only part of me that felt really tired?

I am 43, 5'5" and weigh 130.

I have been training using Hal Higdon's schedules. I used the intermediate for the marathon and the advanced for the half. I have been doing the speed work and the hills as suggested. I am planning on running LA in March, so any help before I start my 18 week training for that would be appreciated.

I have no idea what the course was, but generally excessive quad soreness is due to significant downhill running, more than you are accustomed to. The secondary possibilities are (obviously) weak quads or a major discrepency between the strength of your quads and hamstrings. Other than a range of good quad weightlifting exercises (one-legged squads, leg extensions, etc), downhill running and cycling are great ways to strengthen them.