Its because all the major gay studios are here in SF (red circles).

If you calculate the euclidean center point from all the gay studios (ignoring outliers like CyberBears) it overlaps with Golds Gym SoMa (star shape).

This gym is filled with porn stars. Half the trainers are porn stars or should do porn. We ran into these guys just the other day.

If you workout in SF, do so at this gym. —”★★★★★”

(Source: carnenchiladas)