Hello! Port forwarding VS port triggering in Emule. Which to use?

I already know port forwarding does the job by unblocking port, but is port triggering more indicated for Emule?

I'm reading that port triggering only allows incoming communication on a given port if there is a trigger on that (or another) port. Does Emule trigger the ports it uses for incoming communication? Thank you very much! Sorry if this question is a complete mess ;)