Header Label: customize in single post the text in general option

Hi,
I would like to change the standard HEADER LABLE in general options with a customized one in a single post.
Should I use: Alternate Headings?

If yes How I should use it?

In the link I send as example I would change the text: Cosa apprendi con questo articolo:
with a different text only for that post.

Just to be clear I’d like: leave the HEADER LABLE text in general option as standard and change it in sigle post id I need it.

Thanks for help
gabi

The page I need help with: [log in to see the link]