HGH (growth hormone, somatotropine, somatropin) - a peptide hormone of the anterior lobe of the pituitary gland, which is used in the sport for the muscle relief improvement. Growth hormone or somatropin (from latin: soma - body) gets its name from the fact that the young people it causes a pronounced linear acceleration of growth, mainly due to the growth of the long bones of the limbs. Basic growth hormone concentration in blood is 1-5 mg/ml, while the peaks can be increased up to 10-20 or even 45 mg/ml.