Experiment: Ad Infinitum

Place the tip of your tongue on the roof of your mouth just behind your front teeth.
Contract your perineum, the muscle located between the genitals and the anus. This may be achieved by contracting the anus itself.
Breathe through your nose and feel the energy flow through your body from crown to perineum then up your back to the crown again.
Technically the energy flows through your legs as well. After traveling down the front of your body to the perineum the current runs down the back of your legs, up the front of your legs to the perineum again and up your spine to the crown, like a figure eight.
Circulate the energy through your body in this way for a few moments daily, particularly when you are feeling sexually aroused.