Fig. 1. Properties of the muscle and definition of terms used in the model. These Scyliorhinus canicula white myotomal muscle properties were determined experimentally in the work of Curtin et al. (1998). (A) Force–velocity relationship of the contractile component at different levels of activation. (B) Variation in the SEE stiffness with force and (C) the resulting force–length relationship of the SEE. (D) Phase of activation is defined as the time between the start of stimulation and the start of shortening expressed as a percentage of cycle duration and is demonstrated with respect to one cycle of length change (a negative value corresponds to activating the muscle whilst the muscle is stretching). Duty cycle is expressed as the fraction of the cycle that the muscle/model is stimulated.