Five hours of cycling a week makes your sperm less active, says study

Research provides latest cycling health scare, but authors say men had fertility issues anyway


Simon_MacMichael, December 10, 2010

London cyclist approaching junction.jpg

Men who spend five hours a week or more cycling have lower sperm counts and semen quality than those who undertake most other forms of exercise, not to mention those who lead sedentary lifestyles, according to new research.

The study was led by Lauren Wise of Boston University, with the findings published in the journal, Fertility and Sterility, and followed previous research that suggested that cyclists were more likely than other competitive athletes to have poor quality semen and genital and urinary issues.

"However, we were uncertain whether we would find an association among a sample of men engaged in more moderate levels of physical activity," Dr Wise told Reuters Health.

She added that it was as yet unknown whether cycling itself actually caused the issues with their sperm.

The study sought to establish the relationship between exercise and the health of men’s sperm among 2,200 responents who went to fertility clinics.

Each gave a sample of semen as well as responding to questions regarding their health and the kinds of exercise they undertake.

The authors of the report found that once they had adjusted the data for variable factors such as weight, the type of underwear worn, blood pressure and use of vitamins, their was no greater propensity to have sperm problems among those who undertook rigorous exercise compared to those who did no physical activity.

But once the data were analysed by type of exercise, it was discovered that those who spent five or more hours cycling per week showed double the rate of having a low sperm count, and also demonstrated poor sperm mobility.

Nearly one in three (31%) of men who cycled five hours or more each week had a low sperm count, compared to less than a quarter (23%) of those who did no regular exercise.

Regular bike riders were also much more likely to show poor sperm mobility at 40% versus 27% of those who undertook no physical exercise.

Wise said that the finding might be explained by trauma or an increase in temperature in the scrotal area making bike riders more exposed to the risk of a lower sperm count.

However, she added that since the sample comprised attendees at a fertility clinic, the study might not reflect the population at large, since the men may already have been encountering problems.

"More studies are needed to replicate our findings before they can be considered causal," she concluded.

 

Here we go again, when we were trying for our second daughter - I had some tests and was told that my sperm showed low motility (not moving about as much as they should have been). Said I was a cyclist (there had been scare stories even back then - over 12 years ago) the specialist was pretty scepitcal that it was the cause, citing stress, and any number of other factors that could also affect sperm count and motility.

He advised me to carry on riding, and sure enough next test everything was normal.

tony_farrelly's picture

posted by tony_farrelly [3954 posts] 10th December 2010 - 11:09

Hmm, maybe it's to do with the saddle. Ride standing up on the pedals and the problem may disappear. See how far that'll get you!

OldRidgeback

posted by OldRidgeback [1639 posts] 10th December 2010 - 11:15

How many kids has Chris Boardman got?

posted by nigel_s [27 posts] 10th December 2010 - 11:33

''might be explained by trauma or an increase in temperature in the scrotal area''

My 'scrotal area' gets just as warm in the bath as it does cycling, and unless you're totally de-sensitised down there you wouldn't ride on for long on any saddle that will cause such 'trauma' to the babywand, would you?

For her to then add

''since the sample comprised attendees at a fertility clinic, the study might not reflect the population at large, since the men may already have been encountering problems.''
pretty much obliterates any kind of scientific objectivity instantly and reduces this 'study' to total speculation in my opinion. Even if cycling accounts for the 8% difference between non-athletes, they are already attending a clinic for the same problem which is not necessarily caused by lifestyle and are surely much fitter in other ways. Tosh!

...  Soyez Realiste-Demandez L'impossible ...

posted by Gregoire500 [138 posts] 10th December 2010 - 13:04

Does the research differentiate between those riding wedgies, and those riding recumbents Wink

posted by zoxed [60 posts] 10th December 2010 - 13:07

Total bollox (pardon the pun)

4 kids here all conceived in double quick time!

I spend a minimum of 10 hours a week on the bike for the last 15 years.

posted by gazzaputt [160 posts] 10th December 2010 - 15:12

I've ridden a few bikes in my time. So a low sperm count is probably a blessing....

I'll get me coat.

"I can't believe I ate the whole thing..."

Cooks's picture

posted by Cooks [374 posts] 10th December 2010 - 16:17

Cooks wrote:
I've ridden a few bikes in my time. So a low sperm count is probably a blessing....

I'll get me coat.


Rolling On The Floor

btw..didnt Chris Boardman have about half a dozen kids during his pro racing career?.

Fringe's picture

posted by Fringe [1041 posts] 10th December 2010 - 17:04

Cooks wrote:
I've ridden a few bikes in my time. So a low sperm count is probably a blessing....

I'll get me coat.


Big Grin

If you'd been wearing a coat.....

The_Kaner
FREEEEEEEEDOM!

The _Kaner's picture

posted by The _Kaner [231 posts] 10th December 2010 - 23:10

My father cycled 100km 3 times a week for 15 years.

I am the 6th of 11 yes, ELEVEN brothers and sisters.

Another "study" that tries to get us off our bikes.

Speed now Folds

posted by jmquez [1 posts] 13th December 2010 - 12:18

Mine worked 7 months ago no problems Wink

jobysp's picture

posted by jobysp [145 posts] 13th December 2010 - 21:27

Lance Armstorng is called to mind: even after chemotherapy for testicular cancer and years of riding his bicycle for i'm going to guess more than five hours a week, he still fathered a child without using sperm donations.

but i guess it is lance, so the rules might not apply.

posted by merino [19 posts] 14th April 2011 - 20:43

Fringe wrote:
Cooks wrote:
I've ridden a few bikes in my time. So a low sperm count is probably a blessing....

I'll get me coat.


Rolling On The Floor

btw..didnt Chris Boardman have about half a dozen kids during his pro racing career?.

Yes, but isn't Boardman some kind of superhuman? Even his name sounds like a (admittedly peculiar) Marvel character - Board Man. I'd imagine he funds his low-price bicycle empire through stud fees. Him and Mario Cipollini both (though the latter isn't above providing the odd freebie).

Ghedebrav's picture

posted by Ghedebrav [264 posts] 28th November 2012 - 10:03