what does Caesar want Antony to do when he runs by Calpurnia?

Caesar reminds Antony to touch Calpurnia as he runs by Calpurnia. It was a superstition that if the runner touched the woman who is trying to get pregnant, then whatever curse was preventing her pregnancy would be broken.

Forget not, in your speed, Antonio,
To touch Calpurnia, for our elders say,
The barren, touched in this holy chase,
Shake off their sterile curse.