I dunno. Clinton, when he wasn't biting his lip and shedding a crocodile tears he definately had some machismo there. When he got mad, he'd go beet red, and start with "the finger."
Bush 41, given that he still skydives after topping 80 certainally fills the role.
The Gipper had ballz.
I'm not real sure that Bush 43 had much of a spine given some of his antics.
Carter and JFK can't technically be defined as metrosexual. Remember, it was JFK who captained that PT boat and did some genuinely heroic stuff (unlike Kerry who had to weasel his way out of the service with a bunch of alleged "war wounds"). And Carter, much to his luck, was president before the term metrosexual was coined.
Otherwise, sans hair product, Carter would DEFINATELY be in the running.