Interesting article about male runners and sex of baby
Runner's & Triathlete's Web "File Not Found"
Small study but makes since because of decreased testosterone. Most athletes I know concieved girls. I concieved my first dd when I was running 6 days a week but she was a surprise with one attempt and jump and dump, and always skipped breakfast. So I don't know!
I'm curious what atomic and all the experts thinks, I'm a newbie to all this! I hope it's ok I post this!
Summary:
"To see if running mileage might have a stronger effect than placental burial, Eddie Crawford of the University of Glasgow took a careful look at the effects of weekly mileage, training intensity, paternal age, occupation, and competitive performance on offspring gender in 139 male runners ('Sex Ratio of the Children of Male Distance Runners,' Thesis, Institute of Physiology, University of Glasgow, 1992). Crawford became interested in the topic when a survey appearing in the publication Scotland's Runner revealed that just 23 per cent of the children fathered by runners engaged in serious training were boys.
"Crawford divided his athletes into several categories, including (1) individuals who were not actually training at the time they and their mates conceived a child, (2) subjects who were running between 0 and 30 miles per week when their partners became pregnant, and (3) runners who were training between 30 to 50 miles per week. To these runners, a total of 377 children were born (about 3.4 per man).
"Not running at all - or running less than 30 miles per week - proved to be a good way to increase one's chances of having a male offspring. Overall, about 62 per cent of the children of runners who were taking a break from training or who were running fewer than 30 weekly miles were male.
"However, things changed drastically when weekly mileage soared above 30 miles per week. For those runners who ran between 30 and 50 weekly miles, only 40 per cent of the offspring were gentlemen! According to Crawford, such high-volume running tends to produce dips in testosterone, which in turn produces a decline in the output of boys.
Read more: Do male runners (tend to) conceive girls?