For tendon collagen, an explanation is proposed for the “toe” region of the stress-strain curve. We ascribe the “toe” effect to the fascicle as a whole. Studies of tendon morphology have shown a distribution of crimp angles. In our model, restoring force arises from the elasticity of those fibrils which are already straightened. Resistance of a crimped fibril is assumed to be negligible. The model was found to fit experimental mechanical data for all ages and over the entire “toe” region.