Bustos Sellers, AsunciónMontalvo Pérez, AlmudenaBoraita, AraceliSaco Ledo, GonzaloBrea Alejo, LidiaBarranco Gil, DavidValenzuela, Pedro L.López Maldonado, NereaFerrer Costa, RoserLucía Mulas, Alejandroet al.2026-07-182026-07-182026Bustos‐Sellers, A., Montalvo‐Pérez, A., Boraita, A., Saco‐Ledo, G., Alejo, L. B., Barranco‐Gil, D., Valenzuela, P. L., López‐Maldonado, N., Ferrer‐Costa, R., Esparcia‐Estrela, J., Monteagudo‐López, C., Pinós, T., Santos‐Lozano, A., Lucia, A., & Santalla, A. (2026). Physical exercise intervention in glycogen storage disease IIIa: Feasibility and multisystem benefits. Experimental Physiology, 111(1), 153-166. https://doi.org/10.1113/EP0926440958-06701469-445Xhttps://hdl.handle.net/11268/17289Glycogen storage disease III (GSD-III) is caused by an inherited deficiency of the glycogen debranching enzyme. Affecting the liver, muscle and heart, GSD-IIIa is the most common GSD-III subtype. We evaluated the feasibility and safety of a physical exercise intervention in patients with GSD-IIIa and its effects at the multisystem level. Nine patients participated in a 12 week home-based, remotely supervised programme combining moderate-intensity endurance and resistance exercises. The intervention was safe and well tolerated, with no changes in wellbeing over time and with a decrease in perceived fatigue severity during the intervention. The following significant effects were found at postintervention: Decrease in visceral adipose tissue; healthier cardiac geometry; and increases in peak oxygen uptake, peak power output and knee-extension isometric strength. Although more research is needed, the present findings suggest that exercise should be considered in GSD-IIIa management.engAttribution 4.0 Internationalhttp://creativecommons.org/licenses/by/4.0/Ciencias del DeporteEnfermedad del Almacenamiento de Glucógeno Tipo IIITerapia por Ejerciciojournal article10.1113/EP092644open accessCiencias médicasFisiología humanaMedicina deportivaGoal 3: Ensure healthy lives and promote well-being for all at all agesGoal 10: Reduce inequality within and among countriesGoal 9: Build resilient infrastructure, promote sustainable industrialization and foster innovation