Pubococcygeus muscle

The pubococcygeus muscle or PC muscle is a hammock-like muscle, found in both sexes, that stretches from the pubic bone to the coccyx (tail bone) forming the floor of the pelvic cavity and supporting the pelvic organs. It is part of the levator ani group of muscles.

Function
It controls urine flow and contracts during orgasm. It aids in urinary control and childbirth.

A well-developed pubococcygeus muscle can enhance sex and orgasm in both sexes.

A strong PC muscle has also been linked to a reduction in urinary incontinence and proper positioning of the baby's head during childbirth.

The PC muscle also allows men to move the penis up and down while the penis is erect. This is in essence a Kegel exercise contraction. This is the same action that occurs when the testicles lift up.

Kegel exercises
Kegel exercises are a set of exercises designed to strengthen and give voluntary control over the pubococcygeus muscles. They are often referred to simply as "kegels." These exercises also serve to contract the cremaster muscle in men, as voluntary contraction of the pubococcygeus muscle also engages the cremasteric reflex, which lifts the testicles up, although this does not occur in all men, however. This will make the penis rise, and control can be achieved with practice.

Kegel exercises appear to enable some men to have multiple orgasms and can help with premature ejaculation.

Anatomy
The Pubococcygeus arises from the back of the pubis and from the anterior part of the obturator fascia, and is directed backward almost horizontally along the side of the anal canal toward the coccyx and sacrum, to which it finds attachment.

Between the termination of the vertebral column and the anus, the two Pubococcygei muscles come together and form a thick, fibromuscular layer lying on the raphé (anococcygeal raphé) formed by the Iliococcygei.

The greater part of this muscle is inserted into the coccyx and into the last one or two pieces of the sacrum.

This insertion into the vertebral column is, however, not admitted by all observers.