The Spin Cycle is an obstacle, firstly introduced as the fourth obstacle on American Ninja Warrior 7 in Venice Beach, and then returned on American Ninja Warrior 8 in Atlanta, once again as the fourth obstacle.
It consisted of three spinning metal hoops, in which competitors must use their upper-body and momentum to traverse from one hoop to the other. Since the hoops were tilted, the competitors' body weight caused each hoop to rotate.
Some competitors who didn't make a transition from one hoop to the other on their first opportunity, later lost their momentum and ended up stuck at the lowest point of the cycle, which put them out of reach of the next cycle or landing mat.
Later on American Ninja Warrior 7, the Roulette Row was introduced as the fifth obstacle in Stage Two, which was a supersized version of this obstacle (except the number of hoops was reduced to two and the gap between the hoops was larger).