In My Opinion, and from experience..i would have to say that it depends on the position your in.
if the girl is on top then the girl has more power, she controls everything. =] She's the one that creates the boys orgasm.
and if the boy is on top he controls every thing. typically the male is more dominant anyway, because most are stronger than females, he has the power in sex to hold down a woman and fuck the shit outta of her. lol.
kinda stupid question...because the gurls will say that they are stronger then guys, and the guys will say the guys are stronger then gurls...we can take this convo alll the way back to BC era