Objectives: Temporary genital numbness is a common side effect of long-distance cycling; cases of impotence have even been reported. Recent reports have shown that perineal compression leads to a decrease in penile blood flow. Reduced oxygen tension leads to penile fibrosis, which works counterproductively to the achievement of an erection. The shape of the bicycle saddle could be a factor affecting penile perfusion. The aim of this study is to find out the influence of different saddle designs on penile perfusion.

Material And Methods: In 20 healthy athletic young men (mean age 26.8 years, range 21-31 years) without history of erectile dysfunction, transcutaneous oxygen pressure (PtcO2), which correlates with arterial and tissue PO2, was measured at the glans of the penis using a transcutaneous measurement device. All men were measured in a standing position before cycling, then during cycling in a seated position on a stationary bicycle. Four different bike saddle designs were used: (A) narrow heavily padded seat; (B) narrow seat with medium padding and a V-shaped groove in the saddle nose ("body geometry"); (C) wide unpadded leather seat; (D) women's special wide seat with medium padding and no saddle nose.

Results: During cycling in all seats a decrease in penile oxygen pressure could be observed, reflecting perineal compression. But the differences were unexpected: seat (A) mean PtcO2 11.8 mmHg, decrease in initial oxygen pressure 82.4%; seat (B) mean PtcO2 20.8 mmHg, decrease in initial oxygen pressure 72.4%; seat (C) mean PtcO2 25.3 mmHg, decrease in initial oxygen pressure 63.6%; seat (D) mean PtcO2 62.3 mmHg, decrease in initial oxygen pressure 20.3%.

Conclusions: Cycling in a seated position leads to a compression of perineal arteries with a consequent significant decrease in penile perfusion. But, there are unexpected differences between different saddle types. It was possible to demonstrate that the most important factor in safeguarding penile perfusion is not the amount of padding, but rather a saddle width which prevents sufficiently the compression of the perineal arteries.

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http://dx.doi.org/10.1016/s0302-2838(01)00028-8DOI Listing

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