Explanation

Gliding action describes the way the foreskin may move during sexual intercourse. The foreskin covers the glans penis but may move back and forth over the glans (see illustration). The gliding movement of the foreskin may reduce friction during sexual intercourse. This gliding action was described by Lakshamanan & Prakash in 1980 ^*The outer layer of the prepuce in common with the skin of the shaft of the penis glides freely in a to and fro fashion...

Illustration

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The images on the right illustrate the gliding action of the foreskin during sexual intercourse.

Opinions and research findings

Several genital integrity activists have argued that the gliding movement of the foreskin is important during sexual intercourse.

• Warren & Bigelow claim that gliding action would help to reduce vaginal dryness and that restoration of the gliding action is an important advantage of foreskin restoration. ^*

• A survey by Bensley & Boyle provides some confirmation that gliding action provides protection of vaginal lubrication.^* The authors explain, however, that their subjects were self-selected and a larger sample size is needed.

• O'Hara describes the gliding action:

During intercourse, the natural penis shaft actually glides within its own shaft skin covering. This minimizes friction to the vaginal walls and opening, and to the shaft skin itself, adding immeasurably to the comfort and pleasure of both parties.''

Friction is not entirely eliminated during natural intercourse but it is largely eliminated. Friction can take place in the lower vagina, but only if the man uses a stroke that exceeds the (forward and backward) gliding range of the shaft's extra skin. And in such a case, there will be friction only to the extent that the shaft exceeded its extra skin, which is uncommon since the natural penis has a propensity for short strokes. Primarily, it is the penis head that makes frictional contact with the vaginal walls, usually in the upper vagina where there is ample lubrication....The gliding principle of natural intercourse is a two-way street—the vagina glides on the shaft skin while the shaft skin massages the penis shaft as it glides over it. (O'Hara, p.72)

• Fleiss and Hodges claim: The foreskin's double-layered sheath enables the penile shaft skin to glide back and forth over the penile shaft. (p.24) and The foreskin enables the penis to slip in and out of the vagina nonabrasively inside its own slick sheath of self-lubricating movable skin. (p.26)

• Taylor suggests that the gliding action, where it occurs, may stimulate the nerves of the ridged band and speculates that the stretching of the frenulum by the rearward gliding action during penetration triggers ejaculation. [http://www.cirp.org/library/sex_function/taylor3/

In the first study of its kind, Taves tested the actual force required to penetrate, using a single subject, an apparatus designed to measure the force needed. A ten-fold increase in force was observed in the absence of the foreskin.This confirms the belief of Whiddon (1953) and Foley (1966) that the foreskin makes sexual penetration easier during sexual intercourse ^*.

Not all accept that the presence or absence of the foreskin makes any difference. In Babywatching (1991), Desmond Morris claims circumcision "has no effect, one way or the other, on the sexual performance of the adult male", though he does not discuss gliding action specifically. ISBN 0224060112

Participants in a 2002 peer reviewed study by Bailey (link to abstract) reported: "...Youth also expressed that the foreskin reduced sexual pleasure for men. Some likened the presence of a foreskin to wearing a condom: 'Some boys say that to them it is less sensational to have sex with the condom on ... the same way as when one has the foreskin intact ... unlike a circumcised man they don't experience maximum sensation.'" ^*

Schoeberlein (1966) reports that 8.8 percent of young German males aged 18-22 have phimosis ^*. This may prevent the gliding action. He also reported a wide variation in foreskin length. This could also affect the degree or the existence of the gliding action in different individuals.