Calf strains commonly occur due to tightness in the calf musculature, which may be precipitated by hip and ankle inflexibility and/or glute weakness. During walking or running gait the hip and ankle require a certain amount of flexibility for a proper stride. If the hips and/or ankles are tight due to too much sitting, repetitive athletic endeavors, or wearing high heels, the calf will be forced to work harder during gait.
As calf muscles become tighter, they become shorter and subject to increased tension. Commonly involved calf muscles include the gastrocnemius, soleus, plantaris, flexor hallicus longus, flexor digitorum longus, tibialis posterior and popliteus. Any muscle under these conditions may develop strains, micro tearing, and subsequent scar tissue, which further shortens the muscle. This cycle repeats itself until other tissues become involved, such as the Achilles tendon. Active Release Technique is required to break this cycle by breaking down scar tissue that has developed due to repetitive strain.