Fat reserves won't help prevent muscle protein breakdown. The only way to help prevent muscle catabolism is by consuming protein, which if you are fasting you a

Fat reserves won't help prevent muscle protein breakdown. The only way to help prevent muscle catabolism is by consuming protein, which if you are fasting you aren't doing. If your goal is to lose weight while maintaining as much muscle mass as possible it doesn't seem like IF would be the optimal choice for that. Its not physiologically possible to have muscle protein synthesis exceed muscle protein breakdown unless you consume protein. The body cannot produce essential amino acids and must obtain them from the diet.