This amino acid has been shown to both increase the amount of luteinizing hormone your body makes (which influences testosterone production) and directly instigate greater testosterone production in the testicles. One study reported that subjects taking D-aspartic acid for just two weeks increased their T levels by more than 40%.
CARNITINE
Research shows that supplementing with this modified amino acid supplement increases the number of androgen receptors in muscle cells. Androgen receptors are what testosterone binds to in muscle cells to instigate muscle growth. By increasing androgen receptors, more testosterone can bind to them and encourage greater muscle growth. This is particularly important when taking a supplement that increases T levels, such as D-aspartic acid.
BORON
There is some evidence that this trace mineral can increase levels of free testosterone, the type of testosterone that is not bound in the blood to the carrier protein sex hormone–binding globulin (SHBG). SHBG prevents testosterone from leaving the blood to enter muscle cells and bind to the androgen receptors. So the more free testosterone one has, the greater the potential for muscle growth. Boron may even lower estrogen levels, which further increases testosterone.
GLUTAMINE
You may be familiar with the fact that glutamine can boost levels of growth hormone, which like testosterone, is an anabolic hormone that can aid muscle growth and fat loss. But one study also found that when combined with branched-chain amino acids (BCAAs), as in Anotest, the combination can lower levels of the catabolic hormone cortisol. Since cortisol also impedes testosterone production, this is another way to boost testosterone levels.
BCAAs
The branched-chain amino acids (leucine, isoleucine, and valine) are the most critical amino acids for muscle growth. Leucine directly turns on muscle protein synthesis, and the other two support the building of muscle protein. These aminos have also been shown to lower cortisol levels, both by themselves and when combined with glutamine, further boosting T levels and muscle growth.
