I rarely see any women using the free weights at my gym. About half of the women there are either running on a treadmill or using the stationary bikes, the other half trains with light weights at the machines.
And if I actually see a woman training with free weights they rarely use weights that are heavy. Even the fitness model types do not squat more than 100 pounds.
Almost all ads for protein powder are geared towards men. Women are only targeted by ads for weight loss shakes. I have never seen an ad were women were depicted the same way men are – strong, training like a beast and moving heavy weights around.
There ARE physiological differences between the sexes. Women have less testosterone and a naturally higher body fat percentage. And their lower bodies seem to be stronger in comparison to their upper body (but maybe women just don´t skip leg day).
A woman can build about 2/3 of the muscle mass a man of similar height could build.
BUT! Relative muscle growth is the SAME for both sexes. That means that women build muscle as fast as men do, even with lower testosterone levels. Women can absolutely get strong fast, just like men can.
Many women may be afraid that they will start to look less feminine or appealing if they pick up heavy weights. But remember that women are already starting off with less muscle mass than men. A woman can not build as much muscle as a man (without steroids).
A woman would need to train for years with heavy weights to lose their feminine appearance or body shape. Just putting on some muscle will not make a woman bulky as long as she is not using steroids!
Women with higher estrogen levels even have the advantage of faster recovery because estrogen protects the muscle from damage (this is a very simplified way of explaining this. I won´t bore you to death with scientific facts).
Female pro-athletes often report performance drops during their period. The menstrual cycle can heavily influence a female athlete, especially if she is suffering from PMS. While the menstrual cycle usually does not have physiological consequences, it sometimes affects the mental aspect of training.
Nobody wants to go to the gym if they are in pain and bleeding.
A woman suffering during her period should train with lighter weights or switch to bodyweight exercises. This will not harm the progress as long as the training schedule during the other three weeks is on point.
Bottom line: A woman does not need to train differently than her male counterpart. As long as she eats enough calories (a point many women struggle with) she will build muscle as easily as men do.
Stay strong, fellow superhero! Lift your weights and eat your protein. See you at the gym!