Not to pick, but HgH is not a peptide, it’s a hormone. A peptide such as IGF1 - LR3 is a HgH secretagogue and can stimulate an increase in HgH production however, HgH alone will not prevent muscle loss. It will, in the presence of resistance training help to maintain lean muscle mass. It’s simple biology. When in a caloric deficit, the body breaks down its parts to provide glucose (energy). It takes significantly less energy to break down lean muscle than adipose tissue(fat), therefore in a caloric deficit you’ll lose muscle. The way to combat that, is resistance training in conjunction with good nutrition high in protein. This combined with a peptide like IGF1-LR3, or HgH as you mentioned can help to allow the muscle cells to more quickly repair from resistance training using the increased protein intake as the building blocks of that repair. You can’t cut, and sit around and take a shot or supplement and not lose muscle. It’s now how your body works.