Jim Parker, M.D. and co-founder of Cruzbike, answers some questions about the health aspects of riding regular bicycles.
Are there really serious health risks to the standard riding position?
Unfortunately, yes. According to numerous recent peer-reviewed medical articles there is a real risk of serious injuries to the perineum in cyclist who ride more than a few hours a week. For example, researchers have found genital numbness may occur in 50% or more of serious male cyclists and erectile dysfunction (ED) in 13 to 24%. Some experts claim the numbers could be higher because many men are too embarrassed to talk about it or refuse to acknowledge cycling as the cause.
What is the perineum?
The perineum (detailed pop-up) is the bottom part of the pelvis from the anus forward. It is made of "soft tissues" such as blood vessels, nerves, fat, and muscles and is not well-suited to weight-bearing.
What kind of injuries can the saddle cause to the perineum?
Bicycle riding on a typical saddle causes erectile dysfunction most likely by damaging the arteries and nerves that run through the perineum. Researchers in Italy and Boston found that the more a person rides, the greater the risk of impotence and loss of libido.
Oxygen levels in the genitals of men have been shown to fall 70% to 80% after only 3 minutes on a standard saddle. The risk of cycling-induced ED is higher for heavier men because they exert more compressive force on the vessels. Researchers have reported patients who developed ED after only one long bike ride. A study of bicycling patroll police officers found significantly decreased penile tumescence and rigidity at nocturnal testing when compared to non-cycling men; and 91% of the bicycle-riding officers experienced groin numbness.
What about women and saddle injuries?
Women are susceptible to the same type of injury to the arteries and nerves that supply blood and sensation to the genitals as men. According to a recent article the Journal of Sexual Medicine, women who bicycled at least 10 miles per week had decreased genital sensation and were more likely to have a history of genital pain than a comparison group of women runners.
What type of mileage can cause this injury?
An analysis of 21 published reports on cycling and ED concluded that more than 3 hours of bicycling per week was an independent relative risk (RR) factor of 1.72 for moderate to severe ED. Researchers in Germany found 19% of cyclists who had a weekly training distance of more than 400 km (248 miles) complained of erectile dysfunction. Another study found a 4.2% rate of ED one week after completing a single cycling event of at least 320 km (198 miles) in men who were free of ED prior to the event.
Don’t the new saddles with “cutouts” solve this problem?
No. The problem is not directly caused by the shape of the saddle. The real culprit is the bicycle’s design that places bodyweight directly over the perineum. This is why bicycle saddles with cutouts do not eliminate the problem. Researchers found that, in fact, some of the cutout designs may actually cause the oxygen level in the genitals to drop even faster because the arteries and nerves run horizontally through the perineum and are subjected to greater pressure where they cross the cutout edges.
My saddle is uncomfortable at first, but then I go numb and it doesn’t bother me. Anything wrong with that?
Yes, terribly wrong. Numbness is your body’s way of telling you its nerves are compressed and at risk of cell death.
What is the solution?
If you must ride a standard bike with a saddle, only use the saddle intermittently and briefly. Unfortunately, this technique is difficult to maintain and transfers the body weight elsewhere, often leading to stress injuries in other areas such as the wrists, neck, shoulders or back. The better solution is to ride a Cruzbike or other recumbent that places the perineum in a forward-facing and non-weight-bearing position while fully supporting your back. For bicycle competitors who are not permitted to ride a Cruzbike recumbent during races because of out-dated UCI rules, they should consider training on a Cruzbike, such as the Silvio, and then racing on their standard road bike to lessen the training hours in the dangerous tuck position which compresses the perineum.
What other ways does the standard riding position increase risk of injury?
I would categorize other bicycle-related injuries as either due to chronic repetitive stress (overuse), or collisions/accidents. The recumbent design of the Cruzbike reduces both types of these injuries. Read on...
Other than injuries to the perineum, what overuse injuries can standard bicycle riding contribute to?
First let me say that bicycle riding is an outstanding low-impact form of exercise with proven cardiovascular benefits. Unfortunately, many, many people give up bicycle riding because of annoying aches and pains in the neck, shoulders, wrists, back, and rear-end.
A study published in the International Journal of Sports Medicine found that 85% of recreational riders had some form of musculoskeletal pain. 49% reported neck pain and 30% reported back pain.
The standard bicycle design makes you choose between riding in a vertical position, which is absolutely the worst aerodynamic position you could possibly be in, versus riding in a tuck position, where your lungs are constricted and your neck is fully extended to allow you to see ahead of you. Both positions often place a lot of weight on the hands and wrists. The recumbent position of the Cruzbike takes weight off the wrists, allows the lungs to fully expand, supports the back, and provides a great forward view without arching the neck … all while in an aerodynamic position.
What about injuries from accidents?
Collisions and accidents are caused by a complex array of factors including the bicycle’s center-of-gravity, visibility to car drivers, the rider’s field-of-view, riding skill, fatigue, head position, foot-to-ground speed, etc. The Cruzbike addresses many of these issues.
The Cruzbike was designed to place the rider eye-to-eye with car drivers, maximizing visibility.
We moved the center-of-gravity slightly lower than on a standard bike to make the Cruzbike more stable in a sudden stop or turn.
The Cruzbike allows the rider to maintain an excellent view of traffic and road hazards without neck fatigue. Many accidents on standard bikes are caused by neck fatigue, which leads to dropping the head down and temporary loss of view of road hazards and traffic.
Neck fatigue leads to "head drop"
... and can be fatal.
Moving at high speed with poor visibility of the road ahead is a common danger of road bikes.
If you’ve spent any time on a standard racing/touring bike, then you’ve experienced staring at the pavement next to the front tire because no one can maintain full neck extension indefinitely. As just one recent example of the dangers of neck fatique on road bikes, the world lost 16 year-old champion cyclist Grant Davis, who died of a massive head injury despite wearing a helmet when he rode "head down" into a trailer parked on the side of the road.
What is foot-to-ground speed?
Sometimes the best safety move is to simply plant your feet on the ground. I have watched many people learn to ride the Cruzbike. It’s very easy and quick to get your feet from the pedals to the ground because you are not perched up high on a saddle. That first 10 minutes or so on a Cruzbike, new riders put their feet down a lot. It’s easy to do and will keep you from falling. As new riders get more comfortable they put their feet down less and less. Before long, they are riding 20 or 30 miles at a time and can’t stop smiling.
What about head position?
If you think about it, as a standard touring bicycle moves forward, the head is the farthest point forward. Therefore the head is likely to be the first point to absorb an impact in the event of a frontal collision. Head injuries are the most common cause of serious injury or death in bicycle accidents. On the Cruzbike, the head is preceded in motion by the feet, legs, and trunk. We recently received a report () from a Cruzbike owner involved in a frontal collision. By his account, we might have expected more serious injuries on a standard bicycle. We believe that as the Cruzbike enters widespread use, data will show a lower rate of accidents and serious injuries when compared with standard bicycles.
If riding a recumbent bicycle like the Cruzbike prevents overuse injuries such as ED, why do so many men still compete in triathlons and other bicycle competitions on standard bicycle saddles?
The UCI “locked-in” the basic form of the racing bicycle in 1934 (see our page for more information), effectively banning recumbents like the Cruzbike. Cycling event organizers may allow you to participate on a Cruzbike, but you will probably be disqualified from official recognition or awards. As the medical evidence mounts about the dangers of the standard bicycle saddle and riding position, I think it’s only a matter of time before sanctioning organizations such as the UCI will permit Cruzbikes and other recumbent bicycles into competitive cycling events for safety and liability reasons, even if it means the breaking of many world records.
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