We've just published a paper describing more of the specialist mechanisms by which energy storing tendon function and damage. We've shown the fascicles are coiled like springs to be fatigue resistance but repetitive loading causes them to unwind and become less efficient. We've seen unwinding happens with age, which may explain the age related increase in tendon injury. (January 2014)

C.T. Thorpe, G.P. Riley, H.L.Birch, P.D.Clegg, H.R.C.Screen (2014) Fascicles from energy storing tendons show an age-specific response to cyclic fatiue loading. J Roy Soc Int