Correct. I would be doing some form of weight training or resistance type training as well to make sure my muscles don't evaporate. I'd also eat a high protein meal for my one meal to make sure my body had enough protein to repair/keep muscle on.

I think for most people who are looking for weight loss - this is not as much of a concern and going to the gym would likely be an extra hurdle for them that would make it too hard. So, 1 meal a day is relatively straight forward.