Why My Muscles Won't Grow? Cortisol Stress Hormone Destroy Muscle Tissues There are many reasons why your muscles wont grow or why your muscle growth is retarded. One main culprit for your muscle tissue to in a catabolic and not in an anabolic state is the stress hormone called cortisol. This stress hormone, cortisol, is produced by your body when you are under stressful situations https://www.nfck.or.kr/