Another factor that could have a significant impact on running injuries is road camber. No doubt you always run on the right side of the road facing traffic (unless you’re lucky enough to have a home in Spain!). That’s good for safety reasons. But it also gives you a functional leg-length discrepancy, since your right foot hits the road lower on the slope than your left foot. You’re also placing your right foot on a slant that tends to limit healthy pronation, and your left foot in a position that encourages overpronation. And you’re doing this mile after mile, day after day, week after week, which could lead to hip injuries.
If you can, try to do some of your training runs on a level surface like a bike path or dirt trail. A local track also provides a firm, essentially flat surface that’s great for slow-paced running. Also consider the treadmill – it’s the perfect surface for balanced running. At the very least, a treadmill provides a great surface for beginning runners, runners who are recovering from an injury, and perhaps even marathoners aiming to increase mileage without increasing their injury risk.