the impossible sit-up(often called the olympic sit-up) is completed by asking an individual to lie on the ground in standard, bent-knee sit-up position while one accomplice blind folds or holds a towel or similar item over the eyes and holds the individual's head to the ground. the second accomplice gets into a squatting position with ass bare. the victim is signalled to attempt to sit-up against the pressure applied by the towel to the head. the towel holder simply releases the towel which allows the victim to sit up with nose directly into accomplice two's ass crack. a fart may be added as a bonus. the name "impossible" is intended to entice an overconfident victim into attempting this athletic feat. occasionally, idiotic victims might not even require the blind fold and will simply close their eyes. technique may be modified depending on intelligence level or sobriety of victim.
"Damn Bruce, your abs are ripped! I bet you could be the first guy I've ever heard of that can do an impossible sit-up."