In this Classic Cecil column He speculates that large breasts hinder training so few large breasted women move up to the higher levels of competition.
I worked on a small study years ago on this very subject. I’m afraid I don’t have a reference, since it was 1974 and I can’t keep tract of yesterday’s newspaper.
The research Fellow, who headed the study, speculated that adrenal testosterone might be the reason female athletes lose so much breast tissue when they train at a competitive level. She also wanted to know if the amenorhea associated with intense training was mediated by adrenal testosterone.
Our first, and most difficult step, was finding subjects just starting to ramp up their training to the competitive level. There just weren’t that many female athletes in those days.
We were finally able to come up with 5 subjects. They were between 18 and 23. All had breasts in the B to D range. They had all been joggers or had participated in high school athletics for at least the prior 2 years. Their body fat ranged from 29% to 33% All had regular periods. One had been amemorheic in high school where she ran cross-country track. None were on systemic birth control. None of them had ever been pregnant.
The researcher and her team followed these women for 5 years, measuring serial body fat, estrogen and testosterone levels, as well as thyroid function indicators.
During the first year or so, their body fat went down to 18%-22%. The one who had been amenorheic in the past became so again. Her estrogen level dropped slightly, with no measurable change in testosterone. (Remember, this was in the stone age, levels were ball park at best.) She started with the smallest breasts, which changed only slightly. The other 4 had no changes in hormone levels, however, all four reported a drop of at least one cup size.
In the second year two others stopped having periods with a slight decrease in estrogen. By this point, breasts had all but vanished from all 5. I don’t think Mammogram was mainstream yet. It would have been interesting to see how much breast tissue they actually lost.
By 2.5 years all had ceased menses.
The third year all five had slight elevations in their adrenal testosterone, and significant drops in estrogen levels.
At the end of the five years, the researcher came to the conclusion that adrenal testosterone did indeed play a part in the defeminization seen in olympic level female athletes.
I don’t believe the study was ever repeated. Of course, I move out of the research area all together about then.
The study was truly inconclusive, because of the small test population and the lengthy study period. I am puzzled that her research was never built upon.
Anyway, my two cents.