The wheels of a race car need to run straight and true for maximum performance and to prevent damage to the car. This statement holds true for runners and their wheels. Often we see runners who over-pronate (landing on the outside of the foot and having the ankle roll in) and/or land with the foot laterally rotated. Over time this can place a lot of additional stress on the body joints.
As running is a repetitive transition (POSE to POSE) the high number of foot strikes can soon cause a repetitive strain injury to the body. These niggling injuries can become a showstopper if proper maintenance is not a regular part of the training program.
For example, knee pain can be a sign of a lack of mobility in the ankle and/or the hip joints. Both of these joints are classed as mobility joints as they have (should have) a large range of motion (ROM). The knee on the other hand, or should I say leg, is classed as a stability joint and it is used to stabilise the body when movements occur above and/or below the knee (i.e at hip and ankle) . If we have a loss of mobility at either the hip or ankle the body can start to experience symptoms, usually pain, at the knee joint. Why is this? The human body is a remarkable thing and it has the ability to compensate and find the missing ROM at neighboring joints, in this case the knee. A stability joint should never become a mobility joint!
So what do we do about it? Runners need to stay mobile and spend time doing self myofascial release (SMR) and mobility drills for the ankles and hip joint. For example: http://www.mobilitywod.com/2011/01/episode-142365-tight-it-band-and-hip.html
Warm-up with POSE running drills
Try to maintain form and a consistent speed over each running interval