The present study investigated the applicability of a muscle volume prediction method using only the muscle length (LM), the maximum anatomical cross-sectional area (ACSAmax), and a muscle-specific shape factor (p) on the quadriceps vastii.LM,ACSAmax, muscle volume, andpwere obtained from magnetic resonance images of the vastus intermedius (VI), lateralis (VL), and medialis (VM) of female (n= 20) and male (n= 17) volleyball athletes. The averagepwas used to predict muscle volumes (Vp) using the equationVp = p ×ACSAmax ×LM. Although there were significant differences in the muscle dimensions between male and female athletes,pwas similar and on average 0.582, 0.658, 0.543 for the VI, VL, and VM, respectively. The position ofACSAmax showed low variability and was at 57%, 60%, and 81% of the thigh length for VI, VL, and VM. Further, there were no significant differences between measured and predicted muscle volumes with root mean square differences of 5–8%. These results suggest that the muscle shape of the quadriceps vastii is independent of muscle dimensions or sex and that the prediction method could be sensitive enough to detect changes in muscle volume related to degeneration, atrophy, or hypertrophy.