Women and men gain muscle at about the same rate relative to how much muscle they started with, but women end up gaining less total muscle because they usually start with less muscle to begin with.

When men and women who are healthy and in their 20s to 40s do strength training, they both gain about the same amount of muscle relative to how much they started with—men might gain a tiny bit more, but it’s so small it doesn’t really matter.

When men and women do strength training, men tend to gain a little more muscle size than women—not because they work harder, but because they usually start with more muscle to begin with.

Men tend to gain a little more muscle than women from weight training, not because their muscles grow better, but because they start with more muscle to begin with.

When men and women in their late teens to mid-40s do strength training, they both gain muscle at about the same rate—men might gain a tiny bit more, but it’s so small it doesn’t really mean one sex builds muscle better than the other.

Individuals with low body fat percentages (<15% for men, <25% for women) exhibit diminished capacity for muscle hypertrophy under caloric maintenance or deficit due to insufficient endogenous energy reserves.