I thick the ganglion cyst get bigger at my work but go back to the same size went i driver home & get home & move it a little before i sleep whyisthat

Synovial fluid fills: Ganglion cysts. These are fluid filled sacs and synovial fluid is what lubricates the joint, fluid enters the cyst through a tiny attachment from the joint and makes the cyst large . This is why activity or force seemingly makes the ganglion larger as more pressure in the joint leaks into the cyst. Typically it's a like one way valve into the cyst but they can drain back so they go up and down.

Effort: The ganglion is connected to the synovial space between the small bones of the wrist. The more work that the wrist is doing can express more synovial fluid into the ganglion. When at rest it can return to the space and the ganglion appear smaller. I would suspect that the communication between ganglion and wrist is moderate rather than small.