It is called Urthvarethas,
Meaning that the semen flows upwards through the Chakras in the body to reach the Sahasrara in the head,
This Celibacy is called Naishtika Brahmacharrya.(not allowing the semen to flow down)
Bhishma is a Naishtika Brahmachari.
He is the only Naishtika Brahmachari, apart from Hanuman.
This is the reason, why Devavrataha, was called Bhishma, one who does the Impossible.
In the case of the Grahasthas, so long as their object of physical interaction is to produce progeny without Lust, they are also rated high in the scheme of things.
King Janaka is one such.