I love my bike. It is my primary mode of transport. I ride it to work. I ride it for leisure. I ride it to go shopping. When my doctor takes my blood pressure and tells me I'm in great shape I tell myself that's because I ride my bike. When Al Gore tells me I should change my carbon-spewing ways I say; "take a hike Al, I don't have to change a damn thing - because I ride my bike."
I'm not a biking fundamentalist waging a jihad against cars, but when I'm zipping by a traffic jam of SUV's choking in their own exhaust I feel a warm glow of... smugness. Bicycles are a net-positive in this world. They speed you to your destination. They keep you in shape without destroying your shins and joints and except for the initial cost, they're free to run.
So it was with some dismay that I read recently that too much cycling (read anything more than 3 hours a week – I log at least double that) can result in permanent impotence. This isn't exactly a new issue. It's been bandied about the zeitgeist for a few years now and most serious cyclists are aware of the issue.
Sadly, dick limpness and saddle pressure have been associated for a very long time. Hippocrates, the ancient Greek physician described impotence among the rich inhabitants of Scythia and noted fewer cases among the poor and attributed it to the frequent horse riding by the rich.
More recently, the link was investigated in 1997 with the publication of a Norwegian study in the journal Acta Neurologica Scandinavica. Its authors, Anderson and Bovim, found immediate nerve damage in 22 percent of riders who participated in an annual touring race of 540 km (330 miles). The symptoms ranged from impotence (13 percent) to penile numbness. The study caught the attention of some urologists, and in 1999 another study entitled, "Nerve Injury Associated with Avid Bicycling" was published in the prestigious and widely read (amongst urologists anyway) Journal of Urology.
This was the study that caught the attention of the newswire services and wide-eyed "avid" cyclists everywhere. One of the authors of the study, Dr. Goldstein, has gone on to become the standard bearer for the bicycle = limp dick school of thought. Quoth Dr. Goldstein; "Men should never ride bicycles. Riding should be banned and outlawed. It is the most irrational form of exercise I could ever bring to discussion." Goldstein has estimated that 100,000 American men suffer erectile dysfunction as a result of bicycle riding. Considering that 100 million American's rode bicycles last year, this may not seem like very much, but if you're one of those 100,000 your perspective might be different.
Goldstein and others have come under considerable fire from biking advocates and the bicycling industry in general. While in many ways this is a rearguard action, some of the criticisms are valid. The statistical methodology in a number of studies has been questionable. Some of these studies have been conducted by urologists dealing with men who were already suffering from erectile dysfunction (ED). While a higher proportion of these men were serious cyclists than in the general population, it is methodologically suspect to extrapolate from these figures what the risk factor is for the general population.
Yet studies and statistical rehashings conducted by the biking industry that found (surprise, surprise) that biking makes you less likely to suffer ED are perhaps even more suspect. In reading scientific studies it helps to keep in mind Mark Twain's quote; "there are three kinds of lies: lies, damned lies and statistics."
As yet, no one has conducted the definitive study on the association between bike riding and ED. Perhaps the most respected is a 2002 study conducted by Steven M. Schrader amongst a group of biking police officers. Schrader found an inverse relationship between the degree of seat pressure and time spent in the saddle, and the quality of nighttime erections.
While there's still not enough data to determine what degree of risk is involved in peddling about, it's probably safe to say that something is going on. But what is it? How can something as seemingly innocuous as riding a bike cause you to suffer permanent erectile dysfunction?
The problem appears to be both vascular and neurological. In a typical banana seat (still the most common), most body weight is borne by an area called the perineum, the name given to the area located between the back of the balls and the anus. Through the perineum run both the common penile artery and the pudendal nerve. Any activity which compromises the function of either of these two systems puts the individual at risk of diminished erectile capacity.
The pudendal nerve bifurcates in this area into the two terminal nerves, the perineal which enervates the testicles, (hence, riders often complain of numb-nuts after a long ride) and the dorsal nerve which enervates the penis. As its name suggests, the common penile artery is the main branch of the blood supply leading to the penis. Downstream of the perineum it splits into the bulbourethral artery, the dorsal artery of the penis, and the cavernosal artery. All three are important in achieving a good, solid stiffy.
Either system can obviously be damaged by a sharp impact. It was thought that blood vessels in particular are resilient and elastic in response to non-traumatic stress but evidence is mounting that both nerves and blood vessels can be damaged by long-term wear-and-tear. How this happens is still debatable but it appears that given enough stress, the lining of the blood vessel begins to break down affecting arterial flow. If the stress continues past this point the damage can become permanent.
All this is very sobering to bike enthusiasts like me. Is Dr. Goldstein right? Should men just stop riding bicycles? The answer is clearly no. Moderate bike usage is considered by almost all urologists to be safe, and for those who still like to log a few hours a day in the saddle, there are bike seats that have been designed to minimize the perineal pressure. Of these, the best are apparently the "noseless" bike seats that redistribute the pressure back from the perineum. For cheapos like me who don't want to cough up the extra dough, try tilting your seat down.
Perhaps the best advice is to be aware of what your body is telling you. If you suffer from numb-nuts after a long ride, take this as a serious warning signal. Ditto, if your erections suffer after a long ride. A little bit of caution, it would seem, goes a long way.
Erectile Problems And Cycling Under The Spotlight
Exercise Key To Avoiding Impotence
Traffic Pollution Damages Male Fertility
Driving Can Make You Infertile