Learn the forward scissor on the pommel horse: single-leg swings, leg change in support, amplitude by FIG rule and why the wrists are loaded especially hard.
The forward scissor is an element on the pommel horse: you support yourself in cross or side support, swing the legs in the air one after the other into a straddle and switch them without taking your hands off the horse. In the FIG men's rules it belongs to the element group of single-leg swings and scissors [1].
The honest answer to "How hard is it?": The apparatus is rare, the element is tricky. For scissors the rules demand clear elevation and a large leg separation, and the exercise must consist of swings without visible pauses or visible use of strength [1]. That applies to competition but shows the standard: the scissor is a swing, not a pull-up in support.
And now the part hardly any tutorial says: the authors of a loading measurement call the pommel horse the most painful apparatus for the wrists. In their measurement of 17 elite gymnasts the highest mean peak forces occurred in the front scissor and in flairs (1.5 times body weight, up to 2.0 in some). When performed aggressively, short impact spikes averaging one body weight occurred, with loading rates similar to heel strike in running [2]. At 70 kilos that is about 105 kilos pressing briefly on one pommel. It is an old measurement (1990) on world-class men (TRANSFER), but it explains why you learn the scissor only with build-up and supervision.
Technique note in advance: for the forward scissor we found no federation teaching path. The build-up below follows the principle of the rules (single-leg swing, then scissor, then amplitude) [1] and is practice.
Hands on the pommels or on parallettes, arms straight, shoulders active, body straight. Shift your weight alternately onto one hand (practice). Milestone: 30 seconds of support and ten weight shifts left and right.
In support you swing one leg forward-up and back. The rules call this "single leg swings" [1]. Milestone: ten swings per leg, the pelvis stays up.
Swing one leg forward and the other back and switch the legs very low. That is the preliminary form of the scissor (practice). Milestone: five leg changes in a row without letting go of the hands.
With help on the horse or box, mats all around. The spotter secures the support at the upper arm (practice). Milestone: three scissors with help, arms stay straight.
The rules want a large leg separation and clear height in scissors [1]. At first height at about horse level is enough; later the shoulder line. Milestone: legs at least horizontal, checkable on side-on video.
Turn the placing into an exercise: put sand or soft foam tape on the pommel grip and practise placing so softly that the material hardly moves. Your wrist learns to cushion the impact. That is a practice trick, not a study finding, but it fits the measurement: the spikes arise from hard placing [2].
The men's rules demand clear height and large leg separation in scissors and single-leg swings; above the shoulder line there is no deduction, below it points are deducted [1]. The text gives no fixed degree figure.
The measurement on elite gymnasts shows for the forward scissor some of the highest peak forces on the pommel horse and, when aggressive, high loading rates [2]. Place softly, limit the dose, take breaks.
The preliminary steps yes: support on parallettes or box, single-leg swings, leg changes at low height. The scissor itself needs apparatus and help.
That depends on support strength and feel for swing. Many need a few weeks for the leg change at low height. That is an experience-based estimate, not a study figure.
We found none. The build-up here follows the logic of the rules [1] and practice. So get a coach on board.
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