Considerable attention has been directed towards elucidating factors responsible for mechanical failure of ligaments and tendons [2,10,11]. Still, very few studies to date have examined the effects of repetitive loads on either the transient response or failure properties of ligaments. Panjabi et al.  simulated a subfailure injury during cyclic testing using a single cycle of high subfailure strain and found no statistical difference between the deformation to failure in these ligaments as compared to the controls. However, this study incorporated a relatively small number of preconditioning cycles as opposed to a prolonged duration of repetitive strains.