Imagine straddling an iron chin-up bar, the entire weight of your body centered on that delicate zone between your legs known as the perineum, for an hour. That's what happens whenever you go for a bike ride. Eventually, the area starts to tingle with pain or the first stages of numbness. If you're a guy, the tubes and nerves that fuel erection get squeezed and damaged, leading to predictably disappointing results in the bedroom. If you're a woman—well, let's just say sex is the last thing on your mind after a long day in the saddle.

While some physicians believe that cycling causes impotence and others have gone so far as to call for the banning and outlawing of cycling (as if), there are some easy ways to alleviate the pain that comes with riding a bike.

"When you put pressure on the perineum, you're blocking the nerves and blood vessels that enable erections," says Robert Kessler, M.D., a Stanford University urologist. "That's a [bike] design flaw." Unfortunately, we haven't figured out a better way to ride a bike, so a colleague of Kessler's, Stanford University's Roger Minkow, M.D., set out to address that flaw. He designed a bike saddle, called the Minkow Wedge, that sports a cutaway area under the spot where the perineum rests and is supposed to reduce the threat of saddle-related sex problems.

Brett Doran, a longtime cyclist and assistant manager at Helen's Cycles, a popular Santa Monica, California, bike shop, says seats like the Minkow Wedge (which is manufactured by Specialized) and the Serfas Seat are hits with male and female recreational riders. "The Serfas has a portion cut out from the base, beneath the padding," says Doran, "so its design isn't evident to the eye."

In addition to upgrading your seat to a perineum-friendly "cutaway" model, here are some tips for guarding your future generations:

Pad your shorts: Padded bike shorts—Pearl Izumi makes good ones—can take the squeeze out of riding. They'll also make you look really hard core.

Stand up: Occasionally standing on your pedals for two or three strokes every few minutes keeps the circulation flowing and prevents pain and numbness from setting in.

Find your ideal angle: In most cases, tilting the seat nose slightly downward can provide relief for both men and women.

Get cushy: If you're a recreational or around-town rider, use a wide, comfortably padded seat so that most of your body weight rests on the ischial tuberosity—i.e., your butt bones.

Lie back: On the road, recumbent cycles have only a small (and much ridiculed) following, but in the gym they provide a convenient, safe alternative to uprights.

A final caution: Short stops, falls and collisions can send your crotch crashing down onto the upper tube of the bike frame. Try encircling the iron rod (we mean the bike, Hercules) with a foam pad for protection.