Physiological and performance characteristics in the Spartathlon: A narrative review of scientific findings

Background The Spartathlon is a 246-km ultra-endurance running race, considered as one of the most iconic and physically demanding ultra-marathons in the world. In this narrative review, we aimed to synthesize the available current evidence on the physiological responses, performance trends, and health implications associated with participation in the Spartathlon . Methods A systematic literature search was conducted to identify high-quality scientific studies on the Spartathlon . The databases Cochrane, EMBASE, PubMed, Scopus, and Web of Science were used to retrieve articles published up to December 2025. We found a total of 33 publications in Web of Science, 25 in Embase, 24 in Scopus, 23 in PubMed, and 1 in Cochrane. After removing duplicates and applying the eligibility criteria, a final selection of studies was included for analysis in this narrative review. Results The findings on the cardiac system showed reversible changes in echocardiography and cardiac biomarkers. Running the Spartathlon leads to specific effects on the locomotor system, such as an increase in peak pressure in the forefoot area, an increase in biochemical markers of muscle damage and changes in bone metabolism markers . Notably, the use of oral proton pump inhibitors was associated with a lower incidence of gastrointestinal bleeding. The Spartathlon also showed the highest prevalence of exercise-associated hyponatremia (EAH) of up to 65% as reported in the literature on ultra-marathon running. In addition, running Spartathlon leads to an inflammatory response and an increase in oxidative stress. Conclusions Participation in the Spartathlon leads to several well-documented post-race physiological alterations, particularly affecting the cardiovascular and musculoskeletal systems. Overall, the Spartathlon represents a unique model for studying human physiological resilience and adaptation under extreme conditions.