I feel that if you are training hard enough, it's like a signal to your body to retain it's muscle regardless of your food intake. Now this could be taken to extremes, but I mean in moderation.
Everybody is different, and you have to find what works best for you. Experiment a little, and record what's happening. Also remember that as you progress, your body changes and you may have to add or take away things. I know this sounds generic, but I have food logs and body stats from years ago, and it makes it easier for me to go back and see what I felt worked for me at certain times, and what didn't.
But for peace of mind, you could try the BCAA's and Creatine during your workout. I will do this sometimes if I take my calories lower than normal. About halfway through, I start sipping on it and finish it with my workout.
Then I have my normal meal at the next time.