Running economy for distance runners is a complex multi-factorial measure of running efficiency, which reflects the combined functioning of biomechanical, neuromuscular, metabolic, and cardio-respiratory factors, some of which are hereditary and some of which adapt to coaching.
The Twisted Structure of the Achilles Tendon
A study from Belgium also showed that the Achilles tendon displayed a twisted structure, with the greatest twisting found in the deep (anterior) layer of the tendon (lateral gastrocnemius and soleus).
What are Achilles tendon disorders and what are their causes?
Achilles tendinitis most often occurs due to overuse of the gastrocnemius and soleus contracting to plantarflex the ankle joint.