Insulin-like Growth Factor-1 (IGF-1) is made primarily in the liver in response to Human Growth Hormone (HGH) release. Unfortunately as we age we experience a relative HGH deficiency due to a lowered release from the pituitary resulting in a concomitant loss of IGF-1. The vast number of benefits of IGF-1 centers around muscle development and performance. IGF-1 transports glucose and amino acids into muscle while stimulating muscle DNA. This results in a muscular development in youth and muscle preservation in old age. For the athlete it means peak performance and quick recovery from intense training or injury. Other tissues of the body benefit from IGF-1 because of the affect on DNA and RNA (Ribonucleic Acid and Deoxyribonucleic Acid - are nucleic acids that are an essential part of every living cell). This tends to stimulate a faster production of proteins such as enzymes that help conduct normal metabolism.