Cycling can cause sexual dysfunction in men and woman.
The most commonly reported bicycle-related sexual symptoms in male cyclists are perineal numbness (prevalence of 22–91%) and erectile dysfunction (prevalence of 1.8–50%).
The perineum is a region of the body that runs from the anus to the sex organs.
It contains the nerves and arteries that supply the penis in men and the clitoris and labia in women.
The primary mechanisms leading to perineal numbness and erectile dysfunction appear to be perineal compression of the pudendal nerve within Alcock’s canal and possible trauma.
Sitting on a bicycle seat puts pressure on the perineum, compressing the pudendal nerve.
Pressure on the pudendal artery can add to this compression induced pudendal nerve injury to produce erectile dysfunction in men.
Potential cycling-related disruption of the hypothalamic–pituitary–gonadal axis, specifically in testosterone signaling, may indirectly lead to sexual dysfunction of bicycle riders.
The rider’s position on the bicycle, as well as different types of bicycle seats, affect the degree of pudendal compression, and consequently the degree of resultant sexual dysfunction.
Evidence indicates that the type of saddle used, as well as the position of the rider, has more effect on resultant sexual dysfunction than simply participation in cycling.
When you sit on a chair, your weight is distributed across both buttocks.
However, a narrow bike seat can reduce blood flow to the penis by as much as 66%.