Let’s not call ID a desk job. It’s not supposed to be one. Of course, CAD work is a lot of sitting at a desk and those jobs can be tedious so you have to have some commitment and that does mean days with 10 hours of almost continuous CAD work.When possible, I recommend to work somewhere different than your desk. Having a separate desk for sketching/making is already a great step. Getting a foam cutter to rapidly work in 3D is another step you can easily make. Do a before-lunch walk or run, or meet some friends/colleagues for coffee. The field of embodied interaction has developed some approaches that let designers work more with their full bodies rather than sitting at a desk, also user research in the field is a great way to enrich your work. It depends a lot on the firm you work in how much time you will spend at a desk so it’s good to inquire.