Had dogs 30 years Gaz and to be honest the weight of the dogs didn't have any effect on their seasons.
Re the women athletes, probably more to do with the gear they take lol.
Reminds me of the old joke.
Female Russian athlete goes to the doctor and says to him, "doc I've grown a cock,
do you think it could be because of the steroids I've been taking"?
The doc asks, "anabolic"?
To which she replies, "no doc, just a cock."
Lol I like that one.
I'm pretty sure it's called Amenorrhea in female athletes and a lot of research has been done with regards to body fat and horm