While there are many reasons why runner's get injured I want to share with you what I consider the common causes based on what we treat in clinic.
I find many clients know they don't have the perfect posture when they sit at their desks but assume their running won't be affected. This is wrong, bad posture carries over into your run which can put extra stress on your back and knees. So its important to focus on good running posture which is upper torso straight with head balanced directly over shoulders and lower back not arched.
This is the number 1 cause of running injuries. Training errors basically means your are trying to run too much or too far or too quickly for your body. The body needs time to adapt from training changes and jumps in mileage, intensity or changes in terrain. Muscles need recovery time to they can handle more training demands. If you rush the process you break can down rather than build up. Running experts recommend the 10% rule, which means the maximum speed or distance (note I didn't say speed and distance) you increase by each week is 10%. So if you run 10 miles in the first week, you run 11 miles in the second week and so on.
RICE - Rest,Ice, Compression and Elevation
All of my clients know rice. However I find too many runners focus on the I (ice), and ignore the RCE. So they tend to get stuck in a cycle of ice-and-run, ice-and-run etc without giving the muscles time to heal. Its like dieting every day until 7pm and then pigging out at the all your can eat buffet! Remember the R in RICE means rest, i.e. don't run until the injury is better.