Sexual Purity: can it be achieved or possible?

We will speak on sexual purity and impure hearts. We have to realize that "we are humans" and basic biology tells us that men have an orgasm within 2-3 minutes (whereas women like to joke about 2-minute brothers) and women takes at least 20-30 minutes before she has an orgasm. Women also release a hormone in their bodies that sometimes causes them to be emotionally-connected to their mates, whereas men can just hit it and quit it. We also have to look at what the bible says about it "if you look upon someone in a lustful manner, you have already committ adultery in your heart without even laying a hand or doing the actual act." How can we change our impure hearts? How can we stay pure in the body of Christ? Sin no more.