Shedding Weight, Losing Muscle: Study Links GLP-1 Drugs to Reduced Muscle Mass

"Cardiorespiratory fitness is a potent predictor of all-cause and cardiovascular mortality risk across a range of populations, including obesity, diabetes and heart failure," said Angadi, a cardiovascular exercise physiologist with UVA's Department of Kinesiology. "In a recent study by our group that examined mortality outcomes from almost 400,000 individuals across the world, we found that CRF was far superior to overweight or obesity status for predicting the risk of death. In fact, once CRF was factored in, body weight failed to predict the risk of mortality. This is why it's so important to understand the effects of this new class of drugs on it."

The authors recommend integrating exercise programs and proper nutrition alongside GLP-1 therapy to mitigate muscle loss and improve long-term outcomes. Until more solutions are available, the researchers stress the importance of patient-provider discussions on nutrition, physical activity, and regular screenings for malnutrition and muscle loss risk.

Reference: Zhenqi Liu, Nathan R Weeldreyer, Siddhartha S Angadi. Incretin Receptor Agonism, Fat-free Mass, and Cardiorespiratory Fitness: A Narrative Review. The Journal of Clinical Endocrinology & Metabolism, 2025; DOI: 10.1210/clinem/dgaf335