Measure the box and find the volume of it in Liters

I think about 80% of the “recovery” community on insta are going or have gone down exactly the path you describe. It a more socially acceptable way (on the surface) to channel the disordered urges, and we can even trick ourselves into thinking it “real recovery” and a healthy way to live. Sincerely well done for recognising that strict macros and fitness life isn truly safe or healthy in recovery from a restrictive ED.