More days of aerobic or strength exercise participation were associated with lower GGT in men and women. Serum GGT is derived from the liver , serves as an indicator of general liver health, and is transported with albumin and lipoproteins in the blood . Prior research has shown that although GGT increases acutely after aerobic exercise , lower resting GGT is associated with higher physical activity . The role of GGT in exercise may be through counteracting oxidative stress by breaking down extracellular glutathione and making its component amino acids available to cells for repair . Serum levels of GGT are positively associated with body mass index, alcohol use, and total serum cholesterol .