Are you sitting down? You could be contributing to hip issues, as I explain in this piece at Competitor.com:
Most runners claim they have tight hamstrings. I see it all the time in the yoga classes I teach to athletes. But often, the problem is less in the hamstrings and more in the opposing muscle groups: the quadriceps and, more importantly, the hip flexors.
It’s not surprising that this should be the case. Most of us spend hours every day sitting in chairs and car seats, a position that can slacken the hamstrings and tighten the hip flexors. We then carry this position — an anterior tilt of the pelvis — with us into our sport, which can lead to all kinds of problems, from lower-back pain to hip, knee, and foot issues.
Read more at Competitor Running and in The Runner’s Guide to Yoga.