The Endocrine Society Jun 14 2026 Adults with obesity losing weight with glucagon-like peptide-1 (GLP-1) receptor agonist medications significantly decreased their physical activity, which is essential to protect muscle, according to a study being presented Saturday at ENDO 2026, the Endocrine Society's annual meeting in Chicago, Ill. GLP-1 receptor agonists like semaglutide, liraglutide, dulaglutide and tirzepatide reduce not only fat but also lean muscle mass. This makes physical activity