Mountain Biking Linked to Infertility Risk
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
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.
- Since past studies have shown that biking can interfere with fertility, a
group of researchers wanted to examine what exactly is happening to the
- The researchers found that avid male mountain bikers commonly experience
physical abnormalities in the groin area, intermittent pain or tenderness, and
- Padded seats, padded pants, and shocks for your bike can all reduce the
chance of injury.