My high school gym in Lander, WY had a machine that sat on the floor that you sat on that had R and L leg rests you put each leg on and a knob near the groin that you manually turned yourself that would gradually spread both legs apart so you could stop wherever you wanted and the machine would let you hold the stretch as long as you wanted.  You could stretch your legs toward a splits position at your own pace, mark your progress, and need no one else at all.  Overall, pretty safe and very effective. Just a simple, manual, mechanical device specifically designed to progressively train and condition yourself to do the splits. That was early 90's, and we were a small school with a small budget then. It couldn't have cost much, and I've wondered if other schools had one. Much better than getting hazed by your squad for sure. With this little machine you could work on your splits whenever you wanted and progress at your own pace. Love team bonding, but this be video is appalling. It's HS!