The sensitivity of diffusion tensor imaging (DTI) to muscle fiber size is dependent upon diffusion time. However, there is no consensus on how to interpret data acquired at different diffusion times. In this study we simulated the relationship between muscle fiber size, diffusion time, and the resulting diffusion tensor in models with simplified and histology informed muscle fiber geometry, using a stimulated echo DTI pulse sequence. Maximum contrast between physiologically relevant fiber sizes was found at 130ms for diffusivity, and 170ms for fractional anisotropy measurements. This data may better inform pulse sequence parameter selection when performing DTI experiments in vivo.