Perhaps you refer to the following finding from an actual government study.
You can read more at this link:
Fred On Everything - Women In Combat
From the report of the Presidential Commission on the Assignment of Women in the Armed Forces (report date November 15, 1992, published in book form by Brassey's in 1993):"The average female Army recruit is 4.8 inches shorter, 31.7 pounds lighter, has 37.4 fewer pounds of muscle, and 5.7 more pounds of fat than the average male recruit. She has only 55 percent of the upper-body strength and 72 percent of the lower-body strength…
An Army study of 124 men and 186 women done in 1988 found that women are more than twice as likely to suffer leg injuries and nearly five times as likely to suffer [stress] fractures as men."
Further: "The Commission heard an abundance of expert testimony about the physical differences between men and women that can be summarized as follows:
"Women's aerobic capacity is significantly lower, meaning they cannot carry as much as far as fast as men, and they are more susceptible to fatigue.
"In terms of physical capability, the upper five percent of women are at the level of the male median. The average 20-to-30 year-old woman has the same aerobic capacity as a 50 year-old man."
Having served active duty as a combat medic from 1985-1993 I can honestly say that women in close proximity to mostly male combat units are nothing but a SEVERE distraction.Two sets of standards for the same position is the norm and a male has to walk on eggshells when near one,just as a womans word is taken overwhelmingly more often than a males in civilian life it is ten times worse in the service and no chance of redemption if your ever able to prove your innocence in any verbal altercation.They are a distraction both on the normal sexual thing that occurs anywhere both sexes congregate and they have a totally unfair advantage if they decide to be vengeful.....it can blow a good soldier out of the water.I saw this occur many times while active.no room for females within combat units,i know it may seem chauvanistic but things go MUCH smoother with no natural distractions.Just my educated observation.