Since the behaviors of human breasts are rubberlike, current research explores elastic properties of human breasts. The elastic behavior of breasts is observed through force-displacement measurements in a laboratory setting and characterized through tensile and shear moduli considering individual breast geometries. The breast geometry was analyzed based on specific dimensions, such as cross-sectional areas and lengths in different orientations. The average tensile and shear moduli are estimated to be 5.04 and 0.96 kN/m2, respectively, while both vary from individual to individual in wide ranges. The research approach is highly exploratory and examines apparent elastic properties, but the findings make it possible to quantify elastic capability of live human breasts as a whole and compare them with other soft materials. The conclusion suggests that the shear modulus might be more appropriate to characterize the elasticity of human breasts in terms of developing sportswear.