Cycling does not cause infertility

[Alan]

Or so 'they' say. Those Tripleshotters who haven't yet proven their ability to procreate can now relax, knowing that riding a bike isn't likely to prevent you from going forth and mulitplying...
http://www.telegraph.co.uk/science/scie ... -find.html

And the so-called link to prostate cancer? Nah, that's what I'd call a 'healthy user bias', which is to say healthier men are more concerned about their overall health, and more likely to get screened for prostate cancer and hence, the more they look, the more likely they'll find it...

[Rolf]

It may be worth considering that Dr. Hamer's study did not include as a variable the hour of the day in which men elect to cycle. Unless an early-morning cyclist's reproductive partner follows the same schedule and thus enjoys the same circadian rhythms, I'll hypothesize the impact of ride timing can be one of conscious uncoupling—as Gwyneth Paltrow would put it. I'd guess the sleeping patterns of a male Tripleshotter has a much more significant effect on his reproductive capacity, than any prostate-crushing.

And as for "healthy user bias" completely explaining away the following findings: I ain't no statistician, but that sounds a little overly optimistic (could you be suffering from a critical-analysis-of-medical-studies bias, Alan? ):

Academics found that cycling for as little as half an hour every day doubles the risk of being diagnosed with prostate cancer in the over 50s.

And for those who cycled for eight hours and 45 minutes or more each week, the risk jumped six fold.

[mfarnham]

Yikes...I've been relying on cycling as my sole method of birth control!

Martin

[Alan]

Martin: if what you say is not in jest, then you are playing Russian Roulette and, I'm willing to bet, cycling or no cycling, your pistol is loaded with more than blanks. Be careful out there.

Rolf: You and I could have a very long, detailed, multi-layered argument about healthy-user bias, and the myriad ways in which it causes very smart people to believe things that aren't 'true' and bore everyone in the process.

It would be just easier for me to declare that you are clearly a wanker and leave it at that.

But that would be too easy: Suffice to say a selected, (and small) cohort of men who cycle a lot (like the magic 8 hours and 45 minutes a week cited in this study) differ from the 'average' population of males in so many ways, attributing prostate cancer to their cycling would be as wise as saying "elephants cause peanuts because they are seen often in the same place at the same time." Or maybe "fire trucks cause fires" because there is a temporal/spatial association between the two. Rule number one in epidemiology: Association does not equal causation. You wouldn't believe the incredible numbers of strange, irrational, and sometimes downright harmful things that have been inflicted on the population over the centuries when people get this simple fact wrong and draw erroneous conclusions.

Don't believe me? Then maybe believe the UK's National Health Service:
http://www.nhs.uk/news/2014/07July/Page ... ility.aspx

[Robgrant]

My momma always taught me, correlation does not a causation make.
I guess I need not worry anyway since Strava says I don't spend anywhere near 8hr 45min on the saddle per week.
R