The first thing I did when I noticed this was look at my shoes. I think a good first step is to replace my insoles; they're pretty worn. And I probably should replace my running shoes sooner rather than later. They're not completely worn out, but are getting there.
I'm also thinking it might be a good idea to spend the money on a running coach. In these tight economic times it's easy to want to avoid paying out any extra money unnecessarily. But sometimes, it's necessary. This is my body and I don't want to hurt it. This isn't something I can easily fix on my own - I've been running for a couple of years now and haven't fixed it. And I'm really enjoying running these days.
So I'll turn to a professional. I won't just rely on what friends tell me or what I read in a magazine. For all the reasons I stated above, I'll turn to a professional - especially as I continue to ponder my next big fitness goal. I'm not ready to commit or talk much about it, but I continue to ponder. So I'll turn to a professional.