GLP-1-Based Therapies and Relative Energy Deficiency in Sport Among Physically Active Individuals: Plausible Pathways, Evidence Gaps, and Monitoring Considerations
DOI:
https://doi.org/10.12775/QS.2026.77.75467Keywords
GLP-1 receptor agonists, relative energy deficiency in sport, low energy availability, exercise, weight lossAbstract
Background. GLP-1 receptor agonists and related incretin-based therapies reduce appetite, energy intake, and body mass. Their growing use and discussion in sport raise concern about possible interactions with low energy availability, although a direct relationship with Relative Energy Deficiency in Sport (REDs) has not been established.
Aim. To evaluate how GLP-1-based therapies may intersect with REDs-relevant pathways in physically active individuals while separating established clinical effects, athlete evidence, and untested inference.
Materials and Methods. A structured narrative review used three PubMed/MEDLINE search streams addressing GLP-1 therapies and sport, appetite/body composition/exercise pathways, and REDs or low energy availability. Fifty-five full texts were assessed and the evidence was synthesized thematically.
Results. Trials conducted mainly in non-athletic populations show reduced hunger, cravings, and laboratory-measured intake; gastrointestinal effects may further limit food tolerance. Weight loss includes variable reductions in lean-mass indices, but these measures do not establish loss of contractile muscle, strength, or performance. Athlete studies separately associate problematic low energy availability with reproductive, bone, endocrine, injury, and selected performance outcomes. No prospective study has tested progression from GLP-1 exposure to problematic low energy availability and REDs in athletes.
Conclusions. GLP-1-based therapy should be considered a potential modifying factor within the REDs framework, not a proven cause. Current evidence supports individualized monitoring of treatment indication, weight trajectory, dietary adequacy, gastrointestinal tolerance, training, recovery, body composition, function, reproductive and bone health, and eating behavior. Athlete-specific prospective studies are required.
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