The glans penis acts as an airbag and shock absorber, protecting both the bottom of the vagina and the cavernous bodies of the penis.
To understand what the glans is for, you have to do a bit of anatomy and biomechanics. The penis is in fact formed of two flexible cylinders connected to each other, the cavernous bodies, which become rigid when they fill with blood under the effect of sexual arousal. But these two cylinders are also associated with a third column, the spongy body, which ends in a sort of hollow cap into which the cavernous bodies, the glans, sink.
“The purpose of the glans is to protect the top of the cavernous bodies during penetration and to be flexible and soft to facilitate vaginal penetration,” explains Dr. Marc Galiano, urologist surgeon in Paris, to Figaro. A role of “airbag” but also of shock absorber for the pressures to which the penis is subjected. Because in erection, blood pressure increases considerably in the penis and the cavernous bodies could become injurious without the protection of the glans.
The glans, organ of pleasure
The Greek urologists have realized, by measuring the pressure in the corpora cavernosa of a man whose penis had been amputated because of cancer, the pressure of erection, initially around 15/16 (cm Hg), climbed in the absence of acorn beyond 20/22, during erection. This is not good news because such pressures could, they explain, damage the vessels of the penis. It is furthermore unnecessary to achieve such rigidity as this is far greater than the pressure of about 6 or 7 cm of mercury required for penetration.
Without forgetting, of course, the erogenous role of the glans. “In the mucous membrane of the glans there are sensory receptors which play a role in the pleasure and the excitation and the glans gorged with blood increases in size and thus promotes the stimulation of these receptors”, underlines Dr. Galiano.
Less vaginal resistance as a missionary
The position can also have its importance as demonstrated by researchers at the University of Copenhagen in 1986 thanks to six women volunteers. When the woman is below her partner, rather than as a classic missionary, this increases the vaginal pressure of resistance to penetration from about 7 cm of mercury to 9 cm. More difficult therefore for a somewhat limited erection.
The Danish researchers, however, took measurements again after asking their six volunteers to stimulate their clitoris and they observed a drop in vaginal pressure of up to 6 cm of mercury. In addition, lubrication problems increase (if you do not use lubricant!) And they are more frequent after menopause.
What rigidity for penetration?
In practice, it is complicated to measure the intracavernous pressure but knowing that if your penis can support 500 grams is the weight of the book “The pillars of the earth” (pocket edition) without bending, it is because its rigidity is sufficient for penetration. A force of 500 grams (this is roughly equivalent to 6 cm of mercury of pressure) is indeed what is required to penetrate a lubricated vagina, according to measurements taken in the mid-1980s. However, rely on weight instead. of the last volume of the pillars of the earth (“A pillar of fire”) in large format if your partner has lubrication disorders. The force required can be around 1500 grams of pressure.
Finally, bad news for large penises, in the formula which calculates the force necessary to bend a column, the length is used as a squared denominator. The bigger the penis, the less rigid it will be.