By Todd Norwood, PT, DPT, FACHE and Rajiv R., MD, ABOM
This edition covers:
The relationship between GLP‑1s, body composition, and movement is more complicated than a simple “miracle drug” or “muscle loss” story. When you look closely at new data from Omada’s Insights Lab’s ANSWERS Initiative alongside emerging research, a different narrative comes into focus: with the right support, people on GLP‑1s are not just losing weight, they’re changing how they move, function, and feel in ways that traditional metrics often miss.
GLP‑1 receptor agonists like semaglutide and tirzepatide have reshaped obesity and diabetes care, delivering average weight losses of 15–20% in clinical trials and improving cardiometabolic risk factors for many patients. That success has triggered understandable concern about what’s happening under the hood—especially around lean mass. Historically, about one-quarter of weight lost in lifestyle‑based programs comes from lean mass, and rapid loss can push that percentage even higher. It’s a short leap from those numbers to headlines warning that GLP‑1s are “melting muscle.”
Omada’s 12‑week GLP‑1 body composition study offers a more nuanced view. The Insights Lab followed 245 adults with obesity who had recently started a GLP‑1: 151 received Omada’s GLP‑1 companion program and 94 took GLP‑1s without Omada support. Both groups used connected body‑composition scales and completed surveys at baseline, six weeks, and 12 weeks.
At 12 weeks, Omada participants lost 6.0% of their starting weight on average, compared with 3.2% in the comparison group—meaningfully more total weight, and above the 5% threshold often associated with improvements in conditions like type 2 diabetes and osteoarthritis. More importantly, the “quality” of that weight loss differed. Omada members more than doubled the reduction in body fat percentage (3.3% vs. 1.6%) and saw a larger increase in percent muscle mass (0.6% vs. 0.3%) than the comparison group.
Most people don’t routinely think about their lean mass; they care about whether they can keep up with their kids, take the stairs at work, or get through a shift without pain. That’s where the combination of GLP‑1s and structured support becomes especially relevant.
People living with obesity or diabetes have a high burden of musculoskeletal issues—about 90% and 58%, respectively, have at least one musculoskeletal condition. Chronic inflammation, fatty infiltration, and tendon changes mean that even after weight loss, muscle efficiency and joint health may lag behind.