For
male bicyclists, the road to fatherhood may have just hit a few more bumps.
Two studies in as many months add to recent evidence that bicycling can
be hazardous to a man's reproductive health -- especially for dedicated
mountain bikers. One, released a few weeks ago, found that frequent mountain
bike riding can lower sperm counts, damage the scrotum and possibly reduce
fertility. The other, published in November, showed that even less strenuous
cycling can cause genital numbness and interfere with erectile function.
Studies suggesting a troubling link between cycling and procreation have
been steadily surfacing since a prominent urologist asserted five years
ago that bicycling has caused at least 100,000 men to become impotent,
and the latest research is sure to add to debate among cyclists and physicians.
"Biking
overall is a great sport," said Dr. Ferdinand Frauscher, who presented
the most recent findings at a conference of the Radiological Society of
North America. "It's excellent exercise for the cardiovascular system,
but like other sports -- like skiing and running -- it carries a certain
set of risks."
But not even the latest findings, serious though they are, probably will
knock the millions of cycling men off their bikes. Not only are doctors
reluctant to discourage the activity, particularly when done in moderation,
the cycling industry has developed new designs that can mitigate whatever
potential harm may exist.
Frauscher's study compared 40 mountain bikers with 35 non-cyclists over
one year and found that 90% of the cyclists who rode more than 3,000 miles
a year produced one-third the sperm and had much lower sperm motility
and volume compared with non-cyclists. The cyclists, too, were almost
four times as likely to exhibit scrotum abnormalities, including cysts,
calcifications and varicose veins.
"We believe the microtrauma from shocks and vibrations are the major
reason for the resulting testicular vascular damage," said Frauscher,
a uroradiologist at University Hospital in Innsbruck, Austria.
The
other study, published last month in the Journal of Andrology, followed
a group of 17 bicycle police in Long Beach and found that they had erections
for less time during sleep compared with non-riders. The study was done
by the Centers for Disease Control and Prevention and the National Institute
for Occupational Safety and Health.
Both studies cited the bicycle seat, or saddle as bikers refer to it,
as the chief culprit. The more time on the bike, the more likely there
would be a problem. The saddle's nose often puts extra pressure on the
perineum, the area behind the scrotum, where nerves and arteries run to
the genitals.
Many
bicyclists -- backed by some physicians -- say the recent studies overstate
the risks. They point to countries such as China, where a vast majority
of men bicycle and don't experience above-normal rates of infertility
or sexual dysfunction. Also, they say, fertility difficulties pale in
comparison to the well-known risks of remaining sedentary, a practice
that contributes to obesity, diabetes and heart ailments.
But even the most enthusiastic cyclists concede the saddle can be a real
pain. Cyclists say the key to finding a good one is trial and error and
learning to make small angle adjustments.
"The saddle is the worst part of the bike, always has been, always
will be," said Jim Hasenauer, a board member of the International
Mountain Bicycling Assn. and a Woodland Hills resident. "I know guys
whose garages are full of saddles. It can be like trying to find the holy
grail."
In recent years, bicycle manufacturers have created dozens of new ergonomically
designed saddles, which more evenly distribute a rider's weight, promising
comfort and alleviating pressure on the perineum.
So far, the seats, which offer more padding or feature a triangle-shaped
wedge cut out of its middle, have received positive reviews. In the case
of mountain biking, doctors say the seats -- when combined with a full
suspension system -- can go a long way in warding off any potential fertility
problems. Full suspension systems function like shock absorbers on a car
and create a smoother ride.
But there are a couple of reasons some bikers balk at the improvements.
The first is cost. The new generation of saddles can run $45 to $100,
while full suspension can add as much as $150 to $600 to the overall price.
Also, saddles tend to be heavy and would add burdensome extra weight to
the bicycle. If the precautions are taken, however, there's no reason
to abandon cycling for fear of not being a father, said Frauscher, himself
a mountain biker.
Lance Armstrong (featured
on USRF previously) has been named the Sports
Illustrated Man of the Year.
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