How to change multiple services at once?

There must be a way to do this.
I just took over administering a Nagios server and need to make alot of changes.
At first, I want to change in "Check settings"
Check period*
Max. check attempts*
Retry interval*
Check interval*

And in Alert settings:
Notification period
And who gets alerted. Only have one group to recieve all alerts for now.

This is going to take days if I have to change one service at the time.
Is there a simple way to manage all services, or at least multiple services, at the same time or deploy some kind of default settings to all, but with the possibility to make exceptions afterwards on a few services?

Best regards
Valbjorn