You haven't given us enough context to give a clear answer, but "to fire up" any sort of mechanism often means to start it up, to turn it on, especially with sense of urgency. "I can't wait to start fishing so let's fire up that outboard motor and get this boat out to sea".
It can also mean to make a machine or person work harder, faster. "We're really going to have to fire up the production staff this week to get those big orders finished in time".
As I said, we can only guess how this relates to your "paddles".
not a teacher
Student or Learner