The Role of Testosterone in Muscle Development


You already know that testosterone is the hormone responsible for most masculine traits, including muscularity. But do you know how testosterone works?

You might be surprised to learn that testosterone is actually a steroid produced naturally by the human body. It is a messenger hormone, and one of its functions is to "tell" muscles to grow. Testosterone is crucial for bodybuilders because it dictates your ability to gain size as well as your ability to build strength.

Testosterone is produced in the testes and then released into the blood stream, where around 96 percent of it connects to proteins called albumins and globulin and is used for basic male bodily functions, such as hair growth and sexual potency. The remaining testosterone, known as "free testosterone", is able to interact with other cells to help create changes in the body, such as the growth of new muscle mass.

Testosterone Facts

  • Just as some men are blessed with more fast twitch muscle fibers, some are naturally endowed with higher levels of testosterone than others, and will have an easier time growing their muscles as a result.

  • While females also produce testosterone, men have about 15 times as much testosterone as women. When teenage boys reach puberty, their testosterone levels skyrocket by 1,000 percent, on average.

  • As men, we hit peak testosterone levels around the age of 30. This is, in part, why you see so many great athletes achieve their greatest accomplishments in the late 20s. Unfortunately, it's also why muscle mass and muscle tone are more difficult to maintain after age 30.