FACT VS. FICTION

Adjust bike seat for ease of mind
Tuesday, Dec. 28, 2004

The claim: Bicycle seats can cause impotence for male riders.

The facts: Many people ride their bikes to stay fit, but
could male cyclists be jeopardizing their reproductive
health?

Traditional bike seats are so narrow that they distribute a
rider's weight unevenly, concentrating pressure on nerves
and the arteries that control blood flow to the genitals.
Through the years, some urologists have said that this can
lead to impotence in men, though more than a half-dozen
studies have produced conflicting results.

In 1998, researchers at Boston University showed that a
group of hundreds of healthy male cyclists in their 20s and
30s had a higher rate of erectile dysfunction than a group
of male runners of similar age and health.

In another study, an Austrian researcher found that a
group of men who rode their mountain bikes two hours a day
for six days a week, although in peak physical shape, had
one-third the sperm counts of a group of healthy noncyclists.

But a less alarming study, published in September this year
in The Journal of Urology, surveyed 688 male bikers and
found, after adjusting for age, that the prevalence of
erectile dysfunction among the riders was normal.

So who is right? Experts are not entirely sure.

But laboratory studies that have actually measured pressure
and blood flow in subjects seated on stationary bikes find
that arteries can become significantly compressed during
riding.

This effect can be reduced by pointing the saddle downward a
bit, standing up periodically, and adjusting the seat height
so the knees are just barely bent at the bottom of the pedal
stroke. A wider, ergonomically designed seat can also help;
extra padding, one study found, does not.

The bottom line: Riding a bike can put pressure on critical
arteries, though a proper seat and simple adjustments can
reduce the effect.