-Not necessarily. Isn't it also possible that the men of ancient Greece weren't glued to homophobic stereotypes like those we have carried over from the Victorian era?
Before the spreading of Christianity it was homosexuality that was associated with masculinity as we know it today, you know, the aspirations regading engaging in sports, the military, becoming physically strong, athletic, being corageous, etc. and of course, men loving men was considered the ultimate expression of masculinity. The male bonding was strong and through this they passed down all these concepts of masculinity to younger generations. Greece was highly homocentric. The Greek body ideal symbolised basically two things for these men: it symbolised the embracing of masculinity and it also symbolised male attractiveness. In fact, they used to train naked. Gymnasium means "the place where men train naked". They weren't free from looking down on feminine men I must say because they expected men to embrace masculinity as they defined it.
These are the origins of bodybuilding that have been forgotten and re-interpreted to claim them as heterosexual heritage or inherently representing male heterosexuality even though history shows it was homosexual men (bisexual men also here, of course) who conceptualised all this. Look at Hercules, an extremely sexy demi-god who today is portrayed as highly heterosexual, but he is actually bisexual. Erasure of same-sex desire linked to concepts and depictions of ideal manliness in today's world.
Truth is, heterosexual men defined the ideal female body and that's natural because their attraction and attention are not centered around the male body.