May 8, 2000 (Atlanta) -- Vigorous mountain bikers charging off into the wilderness may inadvertently be damaging their chances of having children, according to Austrian researchers who studied how the popular sport can impair male fertility. They presented their findings here last week at the American Urological Association Annual Meeting.
The provocative research project compared 85 avid male cyclists who racked up more than 3,000 miles a year on their bikes to a group of 31 non-cycling medical students. There were some striking differences between the two groups based on ultrasound studies of the men's genital regions as well changes that could be observed in physical exams.
Almost 95% of the bikers had some kind of observable physical abnormality. About half suffered from intermittent pain or tenderness without any severe trauma to the scrotum. Perhaps more ominous was the fact that 84% of the cyclists had free-floating stones that were detected by the ultrasound exams. These formations suggest possible fertility problems as the damage accumulates over years or decades.
In addition, most of the cyclists had enlargements of various structures within the testicles, and nearly half had significant amounts of stone formation within the testicles.
"We were surprised about the high rate of calcifications," radiologist Ferdinand Frauscher, MD, of Leopold-Franzens-Universität in Innsbruck, Austria, tells WebMD. With its soaring, rugged scenery and a large biking population, Innsbruck was an ideal venue for the research. Frauscher, the study's lead author, says that of the comparison group of 31 medical students, only four had scrotal abnormalities.
Frauscher wanted to look at what was actually happening to the reproductive organs of cycling enthusiasts, since other studies had shown that biking injuries permanently damaged nerves in the groin, leading to erectile dysfunction. While the new research focuses on extreme bicyclists, similar problems can afflict even the occasional rider.
"If you go only once or twice a week, you can also get shocks to the scrotum, and maybe these can cause calcifications, and these can lead to problems with fertility," says Frauscher -- himself an occasional cyclist. As is the case with many sports-related injuries, better equipment can make a difference. Frauscher suggests more padding in the seats as well as padding in bicycle pants. He also says that shock absorbers are advised, although they can make the bikes heavier and, therefore, less attractive to passionate riders.
Another suggestion, says Frauscher, is to get off your bike every hour or so and rest for at least five minutes -- something, he says, many cyclists are loathe to do.
Although the study was small, Frauscher believes it shows a strong trend. He hopes to get a bicycle manufacturer to underwrite a larger analysis.