Theoretically it is possible for girls to practice dumbbells to thicken their arms, but it is 20 times more difficult compared to men. If you want to make your muscles thicker and your arms thicker, you must first have testosterone hormone secretion, and the amount of testosterone hormone secretion in women is only 1/20 of that in men, only testosterone can promote muscle growth, and the low hormone secretion makes it very difficult for women to grow muscles during exercise. Unless the use of exogenous hormones, it is possible to make muscle growth more quickly, so girls practicing dumbbells do not have to worry about the arms will become thick. Most of them are only used as aerobic exercise to exercise, rarely can make the muscles become thicker.