Abstract
Glycogen storage diseases (GSDs) are inherited metabolic disorders affecting hepatic or muscular glycogen metabolism. Hepatic and muscular GSDs diverge fundamentally in pathophysiology, driving distinct clinical priorities and outcome measures. Hepatic GSDs require sustained systemic metabolic control, primarily dietary management, to prevent hypoglycemia and long-term complications such as hepatic adenomas and nephropathy. Muscular GSDs are managed through functional adaptation, including structured exercise training and, in Pompe disease, enzyme replacement therapy, to improve exercise tolerance and motor function. Despite these tailored strategies, complications persist in both forms, underscoring the need for phenotype-driven management and standardized outcome measures across the GSD spectrum.