Exercise is good for sex. Regular exercisers report fewer sex problems and more erotic enjoyment. But extended cycling--more than three hours a week on a standard bike seat--can cause erection impairment (and presumably loss of genital sensation in women). Fortunately, cyclists can still enjoy riding without sex problems--if they watch how they sit on their bikes.
As early as the fourth century B.C., Hippocrates speculated that long-duration horseback riding might harm erections. His observation was largely forgotten--until case reports popped up of erection problems in healthy young men who had no risk factors--except a devotion to bicycling.
Subsequent studies suggested an unusually high risk of erection problems in devoted cyclists. Danish researchers surveyed 800 bicycle racers. More than 300 (38 percent) reported difficulty raising erections for a few days after races.
Researchers involved in the Massachusetts Male Aging Study investigated bicycling and erection dysfunction among the study's 1,709 participants. As time spent cycling increased, so did erection problems.
When you sit, you bear your weight on the bones of you buttocks (the ischial tuberosities or "sit bones"). But many bicycle saddles are too narrow to support the sit bones. As a result, cyclists on banana-shaped seats bear their weight on the soft tissue between the scrotum and anus (perineum), which compresses the nerves and arteries that supply blood to the penis. Nerve compression may produce numbness of the penis. Arterial compression may limit blood flow into the organ, compromising erection. Recent studies show that banana bike saddles reduce blood and oxygen flow to the penis by about 70 percent within a few minutes.
Worse, over time, compression of the arteries that run through the perineum can actually injure them, causing the development of deposits (plaques) that narrow them, limiting blood flow. Elite bicyclists have few plaques in their other arteries, but often have significant plaque formation in the arteries that run through the perineum.
The first sign of trouble is numbness or tingling after riding. These sensations indicate that blood flow and nerve conduction to the penis have been compromised.
In the Massachusetts study, cycling fewer than three hours a week had no effect on erections. In fact, occasional or short-duration riding significantly reduced risk of sex problems. However, bicycling more than three hours a week raised risk 72 percent above what would be expected for the cyclist's age.
"There are only two kinds of long-distance male cyclists," says Boston urologist Irwin Goldstein, who has researched the link between cycling and sex problems, "those who have erection problems, and those who will have them."
Since this problem came to light, the cycling industry has changed seat design. But new seats are effective only if they take weight off the perineum. Cyclists must sit on their sit bones.
In addition, tilt your seat down and your handlebars up. That way you sit in an upright position instead of leaning forward, which compresses the perineal nerves and arteries. It also helps to ride standing from time to time.
So far, all the research on this issue has focused on men. However, the female perineum contains the same arteries and nerves, and narrow bike saddles can be presumed to have the same effects: numbness, reduced blood flow and nerve conduction to the clitoris, and problems with sexual function.
Has anyone experienced cycling-related sex problems? And relief from using a wide seat?