|The Bike Doc
Joined: 08 May 2003
Location: Corpus Christi and Warda, Texas
|Posted: Tue Jun 01, 2004 5:49 am GMT +0000 Post subject:
Does cycling have an association with low sperm count? It is possible based on the findings in some studies I have reviewed.
Follow this link http://jap.physiology.org/cgi/reprint/81/6/2627.pdf for an article on this subject. Here is a quote from the conclusion:
A lower sperm motility (46.2 +/- 19.5%), however, was observed in the cyclists during the competition period when compared either with the other groups during this same period (P < 0.05) or with themselves during the other two periods of study (P < 0.01). In any case, the later phenomenon was attributed to physical factors associated with cycling, such as mechanical trauma to the testis and/or increased gonadal temperature.
Another article studying sperm count and function in endurance trained (long distance runners) and weight trained athletes noted the following:
Sperm density, motility, and morphology were significantly altered only in the endurance-trained runners. In vitro sperm penetration of standard cervical mucus was significantly reduced in the endurance-trained runners.
Follow this link to the abstract in Fertility and Sterility Feb 1993:
Another article in Fertility and Sterility June 1985 has the following abstract:
Twenty male marathon athletes were evaluated by hormonal profiles, psychologic testing, anthropomorphic indices, and semen evaluations. Although total testosterone (T) was significantly decreased in 14 of 20 subjects, free testosterone (FT) was within the normal range in the majority. Ninety percent of subjects (18 of 20) had normal semen analyses. Running mileage, body fat, T, and FT values did not correlate with semen quality. Two athletes with severe oligospermia were found to have the lowest values of T and FT and significant differences in psychologic stress scores. From these data we conclude that (1) vigorous endurance training may be associated with significantly decreased T values but not sperm production; (2) a subgroup of severely oligospermic athletes may be characterized by an "anorectic" symptom complex including higher stress, increased body leanness, and significantly decreased T levels; (3) male endocrine evaluation should be interpreted within the context of physical activity; and (4) factors other than T levels need to be evaluated when one is formulating a therapy plan in oligospermic male athletes.
Follow this link to the abstract:
Athletes who use anabolic steroids (testosterone or synthetic forms of it) can significantly alter their sperm counts for the worse. This can be reversed with stopping of the anabolic steroids. If you are taking nutritional supplements that are touted as helping you build muscle, take this warning seriously, many are tainted with anabolic steroids as some professional and amateur athletes have discovered. Stop any muscle building supplements you may be taking.
Will the seats with the cut out help your sperm count? This has not been studied. What has been studied is the compression of the peroneal nerve and blood vessels that run under the pubic bone. These seats do relieve the compression in this area and help prevent the Dread Dead Dingus (DDD) syndrome. I suspect from the above sited studies, sperm production will be decreased due to the increase temperature to the testicles (sperm production is optimal around 97 degrees) from the snug fitting bike shorts. The good news is that riders do not wear bike shorts around the clock and there is ample time for sperm production to occur in a more normal environment. Wear relaxed fit clothing when not on the bike, use boxers instead of briefs.
Many a male recreational as well as pro cyclist has fathered many a child so the bottom line is that for most men it is not an issue. For those male cyclists with borderline or low sperm counts it may well be an issue and an evaluation by an endocrinologist familiar with male infertility problems is in order.
Paul K. Nolan, MD
AKA: The Bike Doc