Overtraining Syndrome: Pathophysiology, Diagnostic Challenges and Prevention Strategies – A Narrative Review
DOI:
https://doi.org/10.12775/QS.2026.57.72555Keywords
overtrainig syndrome, sports medicine, heart rate variability, cytokine production, RED-S, athlete monitoringAbstract
Background. Overtraining Syndrome (OTS) represents a complex, maladaptative state characterized by a persistent decline in athletic performance and systemic physiological dysfunction. Despite its prevalence in elite and amateur sports, it remains one of the most challenging conditions to diagnose and treat.
Aim. The study aims to provide a comprehensive review of the current physiological frameworks, diagnostic challenges, and modern management strategies for OTS, while integrating classical theories with emerging research on the gut-brain axis and metabolomics.
Material and methods. A narrative review of academic literature from 1980 to 2024 was conducted using databases such as PubMed and Google Scholar. The selection focused on joint consensus statements, clinical trials, and systematic reviews. Analysis was assisted by AI tools for structural organization and linguistic refinement, ensuring adherence to modern scientific writing standards.
Results. The findings indicate that the pathophysiology of OTS is multifaceted, involving systemic inflammation (the cytokine hypothesis), metabolic depletion (the glycogen hypothesis), and structural changes in intestinal permeability (the gut-brain axis). The review distinguishes between sympathetic and parasympathetic OTS phenotypes, each requiring different monitoring approaches. Modern research highlights a significant clinical overlap between OTS and Relative Energy Deficiency in Sport (RED-S), suggesting that low energy availability is a primary driver of the syndrome. Diagnostic methodologies continue to rely on the exclusion of organic diseases, supplemented by longitudinal monitoring of heart rate variability (HRV) and psychological profiling (POMS).
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Copyright (c) 2026 Barbara Głowacka, Hanna Mruzek, Aleksandra Wesołowska, Paulina jasak, Zofia Kania-Bonicka, Sandra Owczarek, Marta Żółtowska, Aleksandra Sobótka, Oliwia Kałwak, Oriana Dziechciarz, Dominika Zgodzińska
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