Impact play

Impact play is a human sexual practice in which one person (the sub, or "bottom") is struck (usually repeatedly) by another person (the dom) for the sexual gratification of either or both parties. It is considered a form of BDSM.

There are number of activities that qualify as impact play.

In erotic spanking the sub is struck either with the top's open hand, or a rigid implement such a paddle, cane or riding crop. In the latter case the activity is often referred to as paddling, caning or cropping. The usual targets for spanking are the and inner or outer thighs.

In erotic flagellation the sub is struck with a flexible implement such a whip or belt. Whips are classified by how many falls they have:

For safety, impact play should be done on areas of the human body well protected by fat or muscle; spots to avoid include the kidneys, neck, tailbone, hipbones, the head and all joints. The usual targets for flagellation are the buttocks and the two areas of the upper back below the shoulder blades. With care, the thighs, the backs of the calves and the chest can be targets as well. Breasts are another potential, but high-risk, target and should only be used with experience.

The use of a whip means that the top must take great care to hit the intended target area, and avoid wrapping; that is when a whip or flogger makes contact with the target area somewhere up its length and the remaining length wraps around the sub's body to deliver a sharp, non-erotic, and possibly injurious off-target blow, such as to the hipbones or ribs. The longer the falls, the more skill is required by the top to land a safe blow. Advanced flogging techniques use a pair of floggers employed in a martial arts style alternating pattern, a technique commonly referred to as "florentining" or "florentine flogging."

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Wikipedia