vigorous choreographic movements subject their external genitalia - when not otherwise supported, restrained and cradled snugly against the lower groin area - to loose, unrestrained instability (i.e. flopping around) due to rapid acceleration, deceleration and gravity forces (because as the body temperature warms up during physical exertion, the scrotal skin naturally loosens, relaxes and droops down in order to moderate the testes at a lower temperature level (or shrinks and contracts when subject to cold to maintain a warmer temperature)); where such floppy movements of the male appendage can be distracting to the dancer.