SECRETS OF MU
ULAR DEVELOPMENT: CHROMIUM PICOLINATE
Chromium, an essential trace mineral, acts as an anabolic nutrient, in concert with the anabolic hormone insulin. The biologically active form of chromium is called glucose tolerance factor (GTF)—a complex of chromium, nicotinic acid (vitamin B3), and three amino acids: cysteine, glutamic acid, and glycine (the same amino acids found in the antioxidant L-glutathione). GTF potentiates the actions of insulin by increasing the binding of insulin to insulin receptors that are located in cell membranes. GTF thus increases the body's sensitivity to insulin, improving the hormone's anabolic effects on muscle.
A scientist at the U.S. Department of Agriculture developed a form of chromium called chromium picolinate (the mineral chromium combined with a substance ordinarily made in the liver that improves chromium absorption and biological activity). Chromium picolinate has proved to be more potent than other forms of the mineral in a number of recent studies.
Many people, especially athletes, don't get enough chromium through their diets: 90 percent of self-selected diets were below the suggested safe and adequate intake of up to 200 micrograms of chromium per day. Physical activity and physical trauma (such as damage resulting from bodybuilding) accelerate the loss of chromium, which can be further aggravated by eating high levels of sugar.
High-protein diets, so common among bodybuilders, also increase the production of "insulinlike growth factor-1" (IGF-1, also known as somatomedin C)—a hormone that mediates, in large part, the actions of growth hormone. As protein intake increases, so do levels of IGF-1 in plasma. Which brings us to the final anabolic nutritional stimulant.