NO. Athletes should not use MK-677 medications or supplements. MK-677, also known as Ibutamoren, is an orally active growth hormone prosecretor. It has the effect of increasing levels of human growth hormone (hGH) in the body. MK-677 is classified as a toxicant in Australia and has significant safety risks associated with its use, most importantly it is not approved for use in humans. As a result, MK-677 is banned for use in sports. In addition, MK-677 lacks toxicity data, and potential long-term side effects in humans are unknown. Therefore, researchers consider the use of Ibutamoren a risk to their health and athletic careers. And MK-677 is not legal as an ingredient in dietary supplements or any other consumer or commercial product. It should only be used for research purposes.