what he says......
If you are not weight training, then you are really just making excuses!
You absolutely need to do weight training as well.
There are many many reasons for that, mainly like Tommy said, you dont want to diet away muscle, you want to increase muscle mass at every opportunity, and dont worry your ratio of fat to muscle will not affect your scale readings that quickly or easily.
Don't make any excuses, get to the gym.
Do you know that there are skinny people that look awful too?