Exercise Conversion Kit

Thanks to a blissmiss idea, I remembered an old Transformers toy I had that turned from a rock into a robot. Why not put this to use on exercise machinery, which takes up too much space (and the ones that don't serve no other purpose)?

The 8,039,984,194-in-one exercise machine converts into 8,039,984,194 different things--okay, I lied, maybe three or four-- but each one can be used for something separate, like a chair for sitting, a table for, uhh, eating, or maybe a small bomb shelter complete with anti-aircraft weaponry. That last part was a bad idea, but I'm sure you get the picture.

This is possibly baked already, but I couldn't find anything exactly like it on several searches.
Oh, and [PeterSealy], before you say "this is baked because you can sit on most exercise machines like a chair" or quite possibly "the ancient Egyptians lifted rocks then sat on them," that isn't the same.