Bicycle Seats and Numbness in Male and Female Cyclists

by Dr. Gabe Mirkin, M.D.

Several studies have shown that male bicycle riders can become impotent from pressing their genitals against a bicycle seat. A study from Yale showed that compression from a bicycle seat can cause loss of feeling in a woman's genitals (J Sex Med 2006;3:1018-1027). Now, a new study from Yale shows that the lower a woman sets her handlebars, the more she bends forward and the harder she presses her genitals against the bicycle seat to cause this loss of genital feeling (J Sex Med, published online March 5, 2012).

Women who suffer the most genital numbness set their handlebars below the height of their seats. Riders set their handlebars low to lower their bodies so they can go faster. More than 60 percent of the force you press on your pedals is lost by the air resistance against you and your bike. So, to go faster, you make yourself lower and narrower.

Most bicycle seats have a round back portion to support your buttocks and a narrow nose in the front. While genital

discomfort during long rides is very common among bicycle riders, it is uncommon in professional bicycle racers. Experienced bicycle racers know how to choose and adjust their seats to prevent discomfort when they ride. They usually:

• set the nose level with, or slightly higher than, the back of the seat;
• adjust the height of their seat post so that they never straighten their knees during pedaling;
• chose a seat with just enough padding to prevent discomfort and width to support their buttocks.

Noseless bicycle seats cause little or no genital discomfort, but racers cannot use noseless seats because they need to press on the nose with their inner thighs to control the bike. A noseless seat also forces riders to increase pressure on the handlebars, increasing their susceptibility to hand numbness.

IMPOTENCE: Impotence is most commonly caused by nerve or artery damage. Exercising regularly helps to keep arteries healthy, so bicycling helps to prevent impotence, as long as it does not damage the local arteries and nerves. Three percent of regular male bicycle riders become impotent, and virtually all of them felt pain or numbness before the problem occurred. When a nerve is pinched or the blood supply to the penis is shut off, a man feels numb. Men who ride with conventional bicycle seats and do not feel numb are not likely to be at risk for impotence. If you feel no discomfort when you ride, keep on riding.

Half of the penis is inside the body and the main blood supply comes from the area just behind the scrotum and in front of the rectum. So bicycle seats that press on that area can cause impotence, while those that do not have a nose and have a widened area to hold your weight on your sitz bones should prevent the problem. Some seats have holes in the middle; the theory is that if there is no pressure behind the scrotum, there will be no numbness.

TIPS TO PREVENT DISCOMFORT FROM A BICYCLE SEAT:

1. Avoid seats with excessive padding. The greater the padding, the deeper you sink into the saddle and the more likely you are to feel numbness.
2. Use a gel saddle that is not too hard and not too soft.
3. Do not tilt the saddle nose downward. The seat should be level or angled slightly upward.
4. Set your handlebars higher to reduce how much you bend forward. The lower you bend, the greater the pressure on your perineum. However, sitting upright increases wind resistance and will slow you down.
5. Change positions and stand often while you ride.
6. Wear thin padding in your pants. Most good bicycle pants come with form-fitted chamois padding.