Multiple studies have demonstrated a decrease in blood flow to the penis while sitting on the saddle as a potential mechanism for erectile dysfunction in cyclists.6,7 However, palsy of the perineal nerves due to microtrauma has also been a purported mechanism that explains both the genital numbness as well as erectile dysfunction seen in cyclists.8,9 In this study, we sought to quantify the absolute increase in pressure related to road or terrain irregularities. We performed this study in a controlled laboratory setting with a mechanism to simulate going over various sizes of bumps. We measured the changes in pressure during this process at a rate of 100 measurements per second. We found that even when going over small bumps, there is a 10% increase in pressure compared with baseline, which increases to 19% with going over slightly larger bumps. Furthermore, the increases in overall pressure appear to be concentrated in very specific areas of the perineum, which were different in men and women. Using a very simple spring-loaded seat post shock absorber, we were able to demonstrate a 50% reduction in the pressure associated with the bumps in a stationary/coasting position.
It should be noted that the bumps used in this study represent a relatively small amount of oscillation compared with riding at 10-20 mph over real road conditions encountered by cyclists. Thus, we believe that for those cyclists engaging in cycling events with prolonged time in the saddle, there may be a role for shock absorption in relieving the numbness and erectile dysfunction seen in this population. Furthermore, it may simply help cycling be less of a pain in the butt.
Written by: Thomas Sanford, MD, National Institutes of Health
1. Goodson JD: Pudendal neuritis from biking. N. Engl. J. Med. 1981; 304: 365.
2. Desai KM and Gingell JC: Hazards of long-distance cycling. BMJ 1989; 298: 1072–1073.
3. Andersen KV and Bovim G: Impotence and nerve entrapment in long-distance amateur cyclists. Acta Neurol. Scand. 1997; 95: 233–240.
4. Marceau L, Kleinman K, Goldstein I, et al: Does bicycling contribute to the risk of erectile dysfunction? Results from the Massachusetts Male Aging Study (MMAS). Int. J. Impot. Res. 2001; 13: 298–302.
5. Awad MA, Gaither TW, Murphy GP, et al: Cycling, and Male Sexual and Urinary Function: Results from a Large, Multinational, Cross-Sectional Study. The Journal of Urology 2017; 199: 798–804.
6. Nayal W, Schwarzer U, Klotz T, et al: Transcutaneous penile oxygen pressure during bicycling. BJU Int 1999; 83: 623–625.
7. Schwarzer U, Sommer F, Klotz T, et al: Cycling and penile oxygen pressure: the type of saddle matters. European Urology 2002; 41: 139–143.
8. Sommer F, Goldstein I and Korda JB: Bicycle Riding and Erectile Dysfunction: A Review. Journal of Sexual Medicine 2010; 7: 2346–2358.
9. Ricchiuti VS, Haas CA, Seftel AD, et al: Pudendal nerve injury associated with avid bicycling. J Urol 1999; 162: 2099–2100.
Read the Abstract