What does Judges 5:18 mean?

The people from Zebulun risked their lives, and so did those from Naphtali—they went right into the thick of the fight, out on the open hills. Judges 5:18 - Modern Text Bible

(This verse praises the tribes of Zebulun and Naphtali for their courage. They didn't hold back or play it safe; they put everything on the line in battle.)