If we want to build and keep lean muscle, or have a lean, toned, and shaped body without the excess body fat, there are key hormones we need to look at:

Cortisol is our stress hormone, released in times of physical or mental stress. It's necessary, but when it goes too high it acts to break down the muscle we do have, prevent or slow new muscle gain, and create and hold onto body fat.

Estrogen and Insulin also play a large role here. 

On the other side we have Growth Hormone, Testosterone, and IGF, Hormones that act to repair muscle, bone, ligaments, etc, build lean muscle, burn excess body fat, and shape our body in both men and women.

But cortisol, estrogen, and insulin work on a sort of seesaw-reaction basis with growth hormone, testosterone, and IGF. 

Raise one side and the other side lowers, and vice versa.

Increase cortisol and we decrease testosterone and growth hormone levels, causing fat gain, preventing muscle gain, and even breaking down the muscle we do have. 

But raise testosterone and growth hormone and we lower cortisol, estrogen and insulin levels.

So while we've covered how to prevent cortisol, estrogen, and insulin from going too high in the above linked articles, in this article we cover how to increase levels of growth hormone, testosterone and IGF.

Let's dive in.