This finding counters previous studies that have suggested male cyclists are at increased risk of experiencing erectile dysfunction (impotence) or prostate problems, such as a frequent urge to urinate.
The new study, which involved almost 4,000 male cyclists, swimmers and runners from five countries, did find that cyclists had a higher likelihood of developing urethral stricture (a narrowing of the tube carrying urine out of the body), which can cause problems with urination.
The cyclists were also, not surprisingly, more likely than swimmers and runners to report genital numbness or saddle sores.
But the risk of numbness and saddle sores could be greatly reduced by raising the handlebars and/or standing for 20 percent or more of the time while cycling, the study also found.
“We believe the results will be encouraging for cyclists,” said Dr. Benjamin Breyer, the study’s lead author and a urologist at the University of California-San Francisco, in a released statement. “Cycling provides tremendous cardiovascular benefits and is low impact on joints. We believe the health benefits enjoyed by cyclists who ride safely will far outweigh health risks.”
The study’s participants
For the study, Breyer and his colleagues analyzed detailed health and activity questionnaires completed by 3,932 physically active men aged 18 and older, who were recruited through Facebook and international cycling, swimming and running groups. The men included 2,774 cyclists, 539 swimmers and 789 runners, and came from the United States, the United Kingdom, Canada, Australia and New Zealand.
The cyclists were divided into two groups: high-intensity cyclists (those who cycled three or more times a week and who averaged 25 or more miles a day) and low-intensity cyclists (those who did not meet that weekly benchmark). None of the swimmers and runners cycled.
Most of the participants — 88 percent — were white, and most were also married. In general, the cyclists were older than the swimmers and runners, but there was no significant difference between the three groups in average body mass index (BMI).
The study’s key findings
After crunching all the data provided by the participants, the researchers found that the sexual and urinary health of the cyclists was similar to that of the non-cyclists, except for the slightly higher risk of urethral stricture among the cyclists and the reports of genital numbness and saddle sores.
The researchers also found no statistically significant differences in sexual or prostate problems between the high- and low-intensity cyclists. Low-intensity cyclists were, however, more likely to develop urethral strictures. An explanation for that counter-intuitive finding may be that men cut back on their cycling after they develop a urethral stricture, say the researchers. Or it may be that high-intensity cyclists have developed a way of cycling that reduces the risk of a urethral stricture-causing injury.
Road surfaces and bike characteristics (such as the type or angle of the saddle) had no effect on the cyclists’ sexual and prostate health, although sitting for more than 80 percent of the time while cycling — or cycling with the handlebar lower than the saddle — increased the likelihood of genital numbness and saddle sores, the study found.
Interestingly, men who wore padded shorts were more, rather than less, likely to report numbness and saddle sores.
“This association could be due to reverse causation in which riders in whom numbness and sores develop subsequently use padded shorts as treatment,” the researchers write.
Limitations and implications
The study comes with plenty of caveats. Most notably, it’s a cross-sectional study, a type of observational study that collects information from a group of people at a specific point in time. Such studies can’t prove cause and effect. So, although this study did not find evidence that cycling leads to sexual and prostate problems, it can’t exclude that possibility either.
To do that, the study would need to take a large group of non-cyclists, randomly assigned half of them to a cycling regimen, and then follow all of them — the cyclists and non-cyclists alike — to see if any differences occur between the two groups in terms of the men’s sexual health and urinary function.
Still, as Breyer and his co-authors point out in their paper, this is the largest observational study to date on this topic that has compared cyclists with other recreational athletes.
They believe the findings should reassure cyclists.
“Our findings suggest,” they conclude, “that the cardiovascular benefits may outweigh any theoretical deterrent of cycling.”
FMI: You can read an abstract of the study on the Journal of Urology website, but the full study is behind a paywall.