During empty stomach am cardio, I have been sweating an ammonia-like smell. I read that I may be using amino acids (muscle) as fuel, and at this time I am in a "negative nitrogen balance" or in a catabolic state.
I've read about two options and I'm wondering which is better for muscle retention and fat loss: 1. Take glutamine prior to cardio, or 2. eat some carbs prior to cardio for fuel.