Dante

Another factor to consider is that men have a normal hemoglobin level ranging from 140 to 180, while women have a normal hemoglobin value ranging from 120 to 160. The higher the hemoglobin the greater the energy and the strength, and the greater the energy and strength the easier it is to do extended exercises and increase muscle mass.

Under what basis? there are many theories to this.

In response to the OP's question - the physiology between men & women... or metabolism/endocrine function differs significantly. It's a testosterone versus estrogen 'thing'. The androgenic effects of testosterone promote the secondary sex characteristics in men; including growth, facial hair, etc, etc... upon reception of T to the AR... or reduction of T to DHT via 5a-reductase to promote greater androgenic effects... while estradiol, a biologically active form of estrogen to promote the female secondary sex characteristics do not promote the similar changes in women as androgens/testosterone do in men.

In essence, it is an evolutionary basis, but it is a role played by the Hypothalamic-Pituitary Gonadal Axis..