Purpose

Hacky Sac, like most sports, consists of properly applying physics concepts with physical performance. Logically it follows that some "tricks" are simply impossible, and others, which may seem impossible, require the proper application of physical priniciples. The trick known as the "Rainbow" is an excellent example of the latter.

The Rainbow uses the leg as the arm of a pendulum with the hip acting as the fulcrum. The footbag is caught on the top of the foot and then the leg is swung backwards and upwards, bending at the knee, causing the footbag's position to change from in front of the individual to behind and altering the direction of the velocity.

In freestyle footbag, the "stall" is the most basic move one may accomplish. Simply put, when one "stalls" the footbag it is placed upon some part of the body and made to stop in such a way as it may be held in that position.

Visually, the simplest stall is the foot stall. The footbag is caught on the top of the foot or shoe (on the toe or laces) and brought to a stop. In a stall, the footbag and the object upon which it is stalled act as a single body. The Rainbow may be performed from either a stalled or active (moving) position.