Growth hormone (HGH)
What does HGH (human growth hormone or Somatropin) do?
HGH is the only substance that can actually cause hyperplasia (muscle cell proliferation) while the use of anabolic steroids can only cause hypertrophy (expansion of existing muscle cells). HGH also increases the synthesis of proteins that may be responsible for hypertrophy.
HGH improves growth of muscle tissue and helps to regulate body composition, body fluids, muscle and bone growth, sugar and fat metabolism, and possibly heart function.