The body of a runner is subject to much wear and tear. The longer and faster the runs, the greater the wear and tear.
Our muscles take most of the wear and tear, which over time, can lead to muscle imbalance, pain and reduced running efficiency.
An example of muscle imbalance would be a weak gluteus medius resulting in overactivity of the gluteus maximus, tensor fasciae latae, and lateral quadriceps.
Muscle imbalance may lead to the development of patellofemoral pain syndrome, and possibly patellar tendinopathy. The overactive muscles themselves may also become painful due to the development of myofascial trigger points.