Riding a bike can cause ED?

Research suggests that riding a bike for long periods can cause temporary erectile difficulties, explains "What to Do about Erectile Dysfunction," a new report from Harvard Medical School. The risk appears highest among men who cycle more than three hours a week.

Sitting on a bicycle for a long time puts pressure on the perineum, the area between the genitals and anus. This pressure can harm nerves and temporarily impede blood flow, causing tingling or numbness in the penis and, eventually,erectile dysfunction. However, one study showed that while a conventional bicycle caused a dramatic (though temporary) drop in oxygen supply to the penis, a recumbent bicycle did not.

Bicycle saddle design has changed dramatically over the years and there are many options. Saddles now offer a cutout down the middle to relieve pressure on the perineum and reduce pressure on the soft tissues. Some research supports this theory and many cyclists find that the cutouts are more comfortable than traditional saddles. Newer saddles, such as the Selle SMP, offer a large cutout and downward facing nose. One study found this design superior in allowing penile blood flow compared with standard saddle shapes.
Another study on saddle shape and penile blood flow found that narrow saddles result in less blood flow than a wider saddle. Computer analysis of pressures showed that a wide saddle allowed more weight to be distributed to the sit bones (ischial tuberosity) and put less pressure less on the perineum than narrow saddles.
If you don't want to switch to a recumbent bike, these precautions may help you prevent cycling-related erectile problems:

-- Wear padded biking shorts.

-- Raise the handlebars so that you're sitting relatively upright. This shifts pressure from the perineum to the buttocks.

-- Use a wide, well-padded or gel-filled seat instead a narrow seat, which places more pressure on the perineum.

-- Position the seat to reduce pressure: Make sure it is not so high that your legs are fully extended at the bottom of your pedal stroke, and don't tilt the seat up.

-- Change your position and take breaks during long rides.

-- If you feel tingling or numbness in the penis, stop riding for a week or two.

If you sit at the front edge of a chair or bench, you'll feel your weight resting on your two "sit bones," known as the ischial tuberosities. For proper skeletal support on a saddle, you must position yourself on these bones. This can cause initial discomfort, especially in recreational cyclists, so the tendency is to lean forward, right onto the perineum. Competitive cyclists (triathletes in particular) also lean forward, but they do it to achieve a more aerodynamic position; they also commonly lean into the seat's nose on turns.
Yet neither your seat nor your position on it will matter if the bike itself is not a good fit, according to Ed Burke, Ph.D., author of seven books on cycling and professor of exercise science at the University of Colorado in Colorado Springs. "If Dr. Goldstein was totally right, everyone in the Tour de France would be impotent or have pain and numbness in the genitals."
Cycling is a great sport, but you don't have to sacrifice your health and comfort to poor positioning or equipment.
In other words: If it doesn't fit, you must not sit.