Synthesised, stored and secreted by somatotropic cells within the anterior pituitary gland in the brain.
Also known as somatotropin or somatropin the predominant role of GH is to stimulate cell growth, regeneration and reproduction. Growth hormone like most other protein hormones, acts by interacting with a specific receptor on the cell surface to stimulate growth. In regard to muscle cells GH increases muscle fiber through sarcomere hypertrophy. Growth hormone increases protein synthesis, promotes lipolysis (the breakdown of fat for energy), calcium retention, increases bone density, reduces the uptake of glucose by the liver, stimulates the immune system, and the growth of all internal organs (excluding the brain). It also plays an important role in homeostasis. Growth hormone effects the metabolic process by promoting gluconeogenesis in the liver – the process whereby protein (amino acids) are broken down into glycogen.
How to boost production naturally:
Exercise regularly using heavy weights and compound movements.
Get adequate sleep (at least eight hours a night).
Supplement with amino acid-based hormone boosters that naturally up-regulate GH production, specifically those that include L-arginine, L-lysine and glutamine.
Do high intensity cardio training that takes you past your VO2 max threshold.
Supplement with melatonin (up to 5mg) and gamma aminobutyric acid (GABA – 1.5-3mg) before bed.
Supplement with vitamin D and include vitamin D-rich foods in your diet.
Follow a high protein diet and limit carb intake before bed.
Limit sugar (especially fructose) intake during the two-hour post-workout anabolic window as it stimulates the release of somatostatin from the hypothalamus, which decreases GH production.
Ghrelin, the hunger-stimulating peptide. IGF-1 is also a primary mediator of the effects of GH. Growth hormone-releasing hormone (GHRH) and thyroid hormone also activates GH release.