Incretin-Based Therapies in Sports: Pharmacological Mechanisms, Performance-Enhancing Potential, and Anti-Doping Implications-A Narrative Review.

Incretin-based therapies, including glucagon-like peptide-1 receptor agonists (GLP-1 RAs) and dipeptidyl peptidase-4 (DPP-4) inhibitors, have revolutionized the management of type 2 diabetes and obesity. Recent evidence suggests these agents may influence athletic performance through effects on body composition, energy metabolism, and cardiovascular function. This narrative review critically evaluates whether incretin therapies could constitute doping under World Anti-Doping Agency (WADA) criteria. We narratively reviewed the literature on incretin pharmacology, metabolic effects relevant to athletic performance, and anti-doping regulations, searching PubMed, Scopus, and Web of Science using terms including "GLP-1 receptor agonists", "DPP-4 inhibitors", "doping", "athletic performance", "WADA", and "sports pharmacology", without date restrictions. GLP-1 RAs (semaglutide, liraglutide, tirzepatide, exenatide) induce substantial weight loss (predominantly fat mass) but also reduce lean mass by 20-30% of total weight loss. Preclinical studies demonstrate enhanced exercise endurance, mitochondrial biogenesis, and glucose uptake via GLP-1R/AMPK signaling. However, clinical trials show no consistent improvement in physical performance in humans. Currently, incretin therapies are not listed on the WADA Prohibited List. While incretin therapies offer theoretical performance-enhancing potential through weight management and metabolic optimization, current evidence does not support classification as doping agents. Continued surveillance is warranted as misuse patterns emerge.