Several times a year I force myself to take a scheduled two week break from climbing, 1 week of no activity (other than walking and stretching) and 1 week of general strength and conditioning (heavy on the strength).
Most climbers (and CrossFitters) periodize by accident. It looks like - Hard, Hard, Hard, Injury, Rest, Easy. I choose this periodization instead - Rest, Easy, Medium, Hard, Easy, Hard, Rest.
Your body needs rest, and it will take it if you don't give it.