A condition in which protein catabolism (breakdown) exceeds protein anabolism (synthesis) resulting in tissues losing protein faster than it can be replaced. A negative nitrogen balance may occur during physical or emotional stress, starvation, when an individual is on a very low calorie diet, or when the quality of protein is poor (e.g. when the diet is lacking essential amino acids). Adrenal cortical hormones, such as cortisone, released during stress enhance protein breakdown and the conversion of amino acids to glucose.
Subjects: Sports and Exercise Medicine.