Ben Benjamin's Corner
By Ben E. Benjamin

Cycling And Your Health

With summer just around the corner, and your clients becoming more active, you may want to steer them toward this popular, and beneficial, type of exercise.
But alert them to the possible dangers as well.

Clients frequently ask therapists what type of' exercise would be good for them, and which kind should be avoided for their circumstances. This may be in the context of building strength, recovering from all injury or maintaining optimal health.The therapist's responsibility is to make recommendations that serve the client's interests. Many practitioners tend to suggest their favorite sport or exercise activity --whether it is running, biking, yoga or tai chi --instead of the activity that best fits that particular client. If the therapist is not trained or well versed in exercise and exercise therapy, the best advice may simply be to make a referral.

The important thing to focus on is to make sure that the exercise fits the person's situation as well as their age, physical condition, body type and interests. For example, running would not be a good choice for all individual with very poor knee alignment or patello-femoral arthritis. Tai chi may be wonderful for some people, but might be difficult for an individual who has trouble raising the arm without pain. Yoga may fit the temperament and interest of many, but not others. Above all, the exercise regimen should be safe for that individual and enjoyable so that the person will stick with it.

One exercise activity that has gained steady popularity throughout the world is both indoor and outdoor cycling. Bicycling is a wonderful form of exercise. It provides a great cardiovascular workout and strengthens our legs, and it puts less stress on the joints than running. Additionally, people of any age and body type can cycle safely, while reaping the benefits of being out in the fresh air. Ani estimated 80 million Americans cycle for pleasure, exercise or as a means of transportation.(1) You probably have clients who cycle regularly, on the road or at the gym, as part of their exercise regimes.

Bike Posture And Injury

But there are also some liabilities that come with cycling. Obviously, a bad fall can result in injury. Another hazard is that normal saddle bike seats call lead to genital dysfunction and other organ damage. Therapists can play a vital role in educating clients about this little-known information so that they can enjoy the benefits of cycling 'without any of the negative side effects.

Bike design has changed over the last two decades, having gone high-tech like everything else. Today's bikes are sleeker, lighter and designed as if you were going to participate in a race. Competitive road racing encourages a forward bent, flexed position to reduce wind resistance and maximize power. For the trained athlete, this position often can be maintained without any negative consequences. However, the forward bent position assumed by the average rider may have unintended harmful consequences. Finding a bike that allows you to sit upright in a balanced position is often very difficult in today's market. Sitting upright places the body's weight on the ischial tuberosities (sit bones), where the weight is supposed to be.

Most bicycles on the market --like racing bikes, road bikes and mountain bikes --force the body to constantly lean the weight forward. The forward-bent position may be slightly more efficient for riding speed, but places tremendous stress on the low back, neck, shoulders, elbows and especially the wrists.

In the forward-bent position, continual tension is placed on the muscles, tendons, joints and supporting ligaments from the hands through the shoulders and into the back. Because these structures are under tension, bumps in the road send shocks of stress through the elbows, the shoulders and the very sensitive wrist ligaments and joints, making all of these areas more vulnerable to injury. Furthermore, the head, one of the heaviest parts of the body, is held up with the neck in extension for long periods of time, fatiguing the muscles of the neck and reducing the circulation and nerve impulses down the arms in many individuals. The low-back ligaments are also in a constantly stretched position, which makes them more vulnerable to damage by sudden additional forces. However, the greatest stress is placed on the wrist joints and their surrounding ligaments.

Mountain biking in this position makes the person especially vulnerable to injury because of the uneven, rough terrain that is navigated. Sudden wrist sprains may occur merely as a result of hitting several bumps in the road. The biker's hands will often lose circulation and become cold in this position. This may be followed by a numbing sensation, setting the stage for injury to the wrists and elbows. The bikes of 30 years ago may have looked clunkier, but they were more in tune with good body mechanics. Sitting upright as you might do at the gym on a stationary bike is great exercise without placing strain on the body's joints and ligaments.

The Alexander Technique is a method of teaching healthy posture, alignment and movement. According to Tommy Thompson, former chair of the Alexander Technique International, the best posture for cycling is "Sitting totally erect ... [It] is the healthiest position for the neck and back. Most recreational bikers ride in a racer's position which strains the body and makes it vulnerable to pain problems."

What can we recommend to bikers in order to stay injury-free? First of all, the recreational biker should try to find a bike that allows the body to remain in an upright position. One can also buy specially shaped handlebars or handlebar extensions, which allow for several riding positions, including being more upright. Serious bikers who race regularly or want to ride a road bike in the forward bent posture should make sure they thoroughly warm up their arms, shoulders, neck and back before riding. They should also take frequent breaks so they can regain an upright position. This biker also needs to have strong and flexible hamstrings and quadriceps. A sufficiently flexible individual should be able to do the following two stretches: Bring the heel of the foot to the buttock with relative ease, stretching the quadriceps; and, place the hands -- or at least the fingertips -- on the floor while bending forward with the knees extended, stretching the hamstrings.

Without preventive care, many cycling injuries occur. Depending upon the cyclist's riding position, biking can either enhance health or contribute to injury. Recumbent road bikes are a good alternative since they are much easier on the body. However, they do take some work to get use to.

The Unspoken Secret

There is a little unspoken secret about bicycles that not many people like to mention -- the majority of bicycle seats are really uncomfortable! Most of us have experienced some discomfort in the perineal area or at the ischial tuberosities (the sit bones), especially after long rides. Some of us develop saddle sores that are highly uncomfortable. Unfortunately, some people suffer from genital numbness due to cycling. This numbness can interfere with our sexual functioning and can indicate more serious medical problems, genital pain, urinary tract dlsorders, erectile dysfunction (ED) and localized atherosclerosis.(2)

Why can cycling cause damage to the genital area? When you sit on a firm surface, like a chair, your ischial tuberosities (located at the bottom of your pelvis) bear most of your weight. This part of your body is uniquely designed for sitting and supporting your weight. There are no organs attached to your sit bones, and they are padded by muscle and fat. There is plenty of blood flow through this area, so you can sit comfortably for long periods of time.(3)

Now, think about the size and shape of a bike seat. Most of them are not wide enough to support us directly under our sit bones, especially for women, whose pelvic girdles are wider than men's. As a result, most bike seats make us sit on our perineums, resting on the ischiopubis rami (the connector bones of the anterior pelvis) and the internal part of the genitals. This area of the body was not designed to be weight-bearing.

The ischiopubis rami are surrounded by nerves and arteries and, in men, erectile tissue and the urethra as well. The male genital actually attaches far back in for erectile functioning. The Alcock canal, which contains nerves and arteries that enter the penis, runs through this area. Similarly in women, the clitoris attaches far back in the pelvis, and the Alcock canal supplies blood and sensation to the genital and urinary tract regions. Sitting on a bicycle seat compresses this sensitive area, cutting off both blood supply and nerve sensation to the genitalia. The normal, narrow, unpadded bicycle seats significantly reduce blood flow through the Alcock canal, and even padded seats are still restrictive. (4)

A recent case study by Irwin Goldstein M.D., a well-respected urologist at the Boston University School of Medicine, shows an association between ED and extended athletic cycling. Goldstein's research demonstrates that cyclists are four more times likely to experience ED than track athletes. (5) In a 2002 study of bicycle policemen in Long Beach, California, 91 percent of participants reported genital numbness, and experiments revealed that they had a significantly lower rate of normal erectile events during sleep than non-cyclists did. (6) Results from the major Massachusetts Male Aging Study show that men who cycle more than three hours per week are at risk to develop artery blockage and long-term damage in the perineal region. (3) In terms of women's health risks, research at Boston University documents urinary tract problems and sexual dysfunction in women cyclists as well, including both road bikers and racers.(7)

Without preventive care, many cycling injuries occur.
Depending upon the cyclist's riding position, biking can either enhance health or contribute to injury.

The good news is that, if we make certain changes, most people do not have to give up cycling. But you may have to give up the seat that came with your bike!

Ben E. Benjamin, with a Ph.D. in sports medicine and education, is the founder and president of the Muscular Therapy Institute in Cambridge, Massachusetts. He maintains a private practice in Cambridge, and has been in practice for more than 35 years. He can be contacted at: 175 Richdale Ave., #106, Cambridge, MA 02140, or via E-mail at: BB@mtti.com.

References

(1) The National Survey on Recreation and the Environment (NSRE): 2000-2001. The Interagency National Survey Consortium, Coordinated by the USDA Forest Service, Recreation, Wilderness, and Demographics Trends Research Group, Athens, Georgia and the Human Dimensions Research Laboratory, University of Tennessee, Knoxville, Tennessee.

(2) Marceau, L., K. Kleinman, I. Goldstein and J. McKinlay. "Does bicycling contribute to the risk of erectile dysfunction? Results from the Massachusetts Male Aging Study (MMAS)." International Journal of Impotence Research 13, 2001: 298-302.

(3) Goldstein, I. "Erectile Dysfunction and bicycling." Institute for Sexual Medicine Publications, Boston University Medical Center. Available at: www.burnc.bu.edu/ Departments/PageMain.asp?Page=7032&DepartmentID=371. Accessed 5 March 2004.

(4) Jeong, S.J., K. Park, J.D. Moon and S. B. Ryu. "Bicycle saddle shape affects penile blood flow." International Journal of Impotence Research 6 2002: 513-517.

(5) Parker-Pope, T. "New studies connect impotence to cycling." The Wall Street Journal. Available at: http://online.wsj.com/
article/O,,SB1034621062928108316.djm,00.html. Accessed 14 October 2002.

(6) Schrader S.M., M.J. Breitenstein, J.C. Clark, et al. "Nocturnal penile tumescence and rigidity testing in bicycling patrol officers." Journal of Andrology 23 2002: 927-934.

(7) LaSalle, M.D., Salimpour P., Adelstein M., et al. "Sexual and urinary tract dysfunction in female bicyclists." Presented at the 94th Annual Meeting of the American Urological Association, Dallas. 4 May 1999.

(8) Taylor, K.S., A. Richburg, D. Wallis, and M. Bracker "Using an experimental bicycle seat to reduce perineal numbness." The Physician and Sportsmedicine 30 2002: 5. Available at: www.physsportsmed.com/ issues/2002/05_02/taylor.htm. Accessed 5 March 2004.