Cardiac Adaptations in Endurance Athletes: A Bibliometric Analysis of Exercise‑Induced Physiologic Remodeling.

Background: Endurance exercise induces cardiovascular adaptations known as exercise-induced physiologic remodeling of the athlete's heart, including sinus bradycardia, chamber enlargement, enhanced vagal tone, and atrial and ventricular remodeling. These changes are generally physiologic, but concern remains about their association with arrhythmias and long-term outcomes. This study aimed to characterize the research landscape, identify influential contributors, and explore emerging themes in this field. Methods: A bibliometric analysis was conducted using the Web of Science Core Collection database. Publications were retrieved from inception through June 11, 2026, yielding 754 results. Annual trends, leading countries, institutions, collaboration networks, and keyword co-occurrence were analyzed using VOSviewer and organized using Microsoft Excel. Results: Publication output grew steadily from the 1990s and plateaued from the mid-2010s onward, without a sharp inflection point. The United States (146) and Italy (126) led national output, followed by England (87) and Australia (77); 36 countries met the network threshold. Institutional output was distributed, led by Liverpool John Moores University, Harvard University, and KU Leuven, while citation strength clustered around Belgian and Italian hubs. Exercise, echocardiography, athlete's heart, and endurance emerged as dominant keywords. Top-cited works date largely to 1994-2002, with citations accumulating over decades. Conclusions: This field has grown through incremental refinement of a stable question rather than a single catalyst, with a distributed evidence base. Influential work treats athlete's hearts as benign by default, while emerging themes suggest growing attention toward identifying which athletes deviate toward pathologic remodeling. Cross-hub collaboration is needed to resolve whether an athlete's heart is one phenomenon or several.