Chair flying is always a good exercise. For example, if you are working on power-off stall recoveries, you can practice what you have learned at home. Sit in a chair, close your eyes, and imagine doing the pre-maneuver checks applicable to the trainer you are flying. Then you can pull the power back, visualize you are seeing the airplane slow down and the nose rise, the ultimate stall, and the recovery. It can be very effective in locking down those procedures. But they need to be tailored to what you are doing and the airplane you are training in. That's a discussion between you and your instructor.
I once had a student who broke his leg and was out for 6 weeks. I gave him some chair flying exercises. He flew better on the first flight after his return than on the last flight before he broke his leg.