“…The fascicles themselves are subdivided into muscle fibres by the thinner and more randomly oriented collagen fibres of the endomysium layer, which is a continuous planar network that surrounds the muscle fibres (Purslow, 2002, Purslow, 2008, Purslow and Trotter, 1994. Elegant work performed by Purslow and co-workers (Purslow and Trotter, 1994, Purslow, 2005, Purslow, 2008, Lewis and Purslow, 1989, Purslow, 1985, Purslow, 1999, Purslow, 2002, Purslow, 2010, Trotter and Purslow, 1992 and others has allowed the connective tissue structure to be observed with the muscle fibres removed, see Figure 2, and the collagen fibres in the connective tissue have been shown to reorient with changes in muscle length (Purslow, 2002, Purslow, 2010 and be efficient in myofascial force transmission (Purslow, 2008) and the perimysium has been suggested as a mechanism to facilitate intramuscular sliding (Purslow, 2010). However, more analysis of the internal mechanisms resisting externally applied loading is needed to explain the experimentally observed stress strain relationships in passive skeletal muscle presented in (Calvo et al, 2010, Morrow et al, 2010, Nie et al, 2011, Yamada, 1970, Martins et al, 1998, Van Loocke et al, 2006, Grieve and Armstrong, 1988, Vannah and Childress, 1993, Zheng et al, 1999.…”