You've started Ozempic, Wegovy, Zepbound, or Mounjaro. The weight is finally moving. So why does every doctor and dietitian keep saying the same thing: "You need to be lifting weights." Here's why. Peer-reviewed research shows that 20 to 40 percent of the weight you lose on a GLP-1 medication can come from lean body mass, including muscle and bone, not fat. The good news: strength training two to three times a week prevents most of it. Here's the science of GLP-1 muscle loss, what the research recommends, and how STRIDE Fitness strength classes are built for exactly this.