William,
Well that depends of how long does a "few weeks" last.
If you're a veggie, you're sources of protein are well limited. Whenever you train, either MA or weight training, or bike riding or swimming, whatever, you'll eventualy be breaking protein down (on different levels, to different extents). Unless you have a protein source you'll not re-build this protein back. So gradually you'll have muscle breakdown. How fast you'll notice that is really a matter of what practice you take.
My advice would be to keep the soy protein. Even if you quit practice, I don't think a "proteinless" diet is any healthy...
" I'd say I'm sorry to disappoint you, but I'm not. I excel at not giving a $hit. Experience has taught me that interest begets expectation, and expectation begets disappointment, so the key to avoiding disappointment is to avoid interest. A equals B equals C Equals A, or whatever. I also don't have a lot of interest in being a good person or a bad person. From what I can tell, either way, you're screwed. Bad people are punished by society's laws, and good people are punished by Murphy's Law. So you see my dilemma."
-- Georgia "George" Lass