Here are a couple of things from the website Paul linked:
Causes of athletic amenorrhoea:
The sex hormones can be disrupted by a number of events, including:
Low body fat levels – the female body won't menstruate below a certain percentage of body fat.
Exercise – physical exertion prompts the release of certain hormones, such as beta endorphins and catecholamines, and high levels of these hormones seem to interfere with the interplay of oestrogen and progesterone.
Things to remember
Amenorrhoea means absence of the menstrual period.
Female athletes or women who perform considerable amounts of exercise on a regular basis may be at risk of developing athletic amenorrhoea.
Causes include low body fat levels and the effects of exercise related hormones on the menstrual cycle.
This phenomenon is not an abnormal occurence and does not necessarily mean someone is unhealthy. I had this happen briefly when I was a swimmer in high school. I worked out really strenuously and continuously for at least 2-2.5 hours a day. I was in fantastic shape, healthy and did not have an eating disorder. As soon as the pace of my training level dropped a little, all was back normal. This is something that female cadets at the service academies often experience in their first summer of training due to the high level of physical activity. The academy literature even mentions that it is expected to occur. The cadets eat over 4000 calories a day and receive the great health care.
I'm an experienced woman; I've been around... well, alright, I might not've been around, but I've been... nearby.
~ Mary Richards (Mary Tyler Moore Show)
that's why i don't mestruate like i used to ray! my body fat is above 6000% so my pussy is just plugged up with fat rolls. no wonder my cunt had that weird swelling going on and all that blood burst out when i popped it with a hammer against the kitchen counter. i guess i just had pussy blood buildup for about 2 years. enough to gargle with .
Yo HO!! Just got me a code red and some funyons big dawg!!! SHIT YEAH! - Ray, excited about his breakfast
you don't contract hiv by being an athlete. you don't develop brain tumors from running long distances. you do, however, affect your menstrual cycle by exercising. let's say this: let's say that for men, when you start training hard and can start running ultra-marathon distances (fifty or more miles), that you need to maintain a body fat percentage of 10%, otherwise you suffer a 95% risk of developing disabling brain tumors. the drawback to having the 10% body fat is that you lose thirty seconds off your mile times. so, would you then say that the guy who's breaking records yet has three brain tumors and has long-term memory problems as well as diminishing vision, deafness, and searing headaches, do you say he's "super fit"? relate this to what's being discovered about nfl linemen. you might call them "super fit" because they perform their job well, but they're life expectancy is significantly shorter than most other people and a large proportion of them suffer from sleep apnea.
your examples separate cause from effect. try again. and yes, i will jump on your case if you say something that perpetuates ignorance about a subject. especially if it hurts people. i would hope people would jump on my case if i said the best way to climb 13's and 14's by next year is to go on a nine-hundred calories a day diet.
and great loves will one day have to part -smashing pumpkins