Sexual stimulation is a fickle beast. It can be here one minute and gone the next. Movie and TV shows would have us believe that men can achieve an erection anywhere at any time. The truth of the matter is all men need three things to get everything working down there: privacy, sufficient time, and emotional intimacy.

For a penis to become erect, it requires around 130 milliliters of blood. Unfortunately, there’s a lot that can get in the way of that blood reaching a man’s penis, such as hormones, psychological mood, quality of the relationship, and quality of previous sexual experiences.

Some men suffer from anatomical conditions that can impede on their sexual performance. These conditions include one where the skin of the penis cannot be pulled back — known as Phimosis — congenital penile curvature — when a man is born with a penis that is typically curved downwards — and Peyronie’s Disease, which causes the penis to slowly curve upwards or to the side.

The good news is there’s a lot that men can do with regard to their lifestyle to protect their erection capacity, including have sex only when they wish to do so, creating the right conditions for sex, increase their levels of physical exercise, controlling body weight, adopting a Mediterranean diet, and quitting smoking.