Concepts, measurement, and influencing factors of durability in endurance runners: a scoping review

Background While VO₂max and lactate threshold have long been considered core determinants of endurance performance, these indicators primarily reflect relatively static physiological capabilities and are insufficient to explain the performance decline over time in ultra-endurance events such as the marathon. Increasing research is focusing on athletes' ability to maintain performance under conditions of cumulative fatigue, proposing "durability" as a new concept to supplement traditional endurance indicators. Objective This study aims to systematically review and map the current landscape of endurance runner durability and related physiological resilience research, clarifying the research scope, concept usage, and methodological characteristics of this field. Methods This study employs a scope review design, based on the PCC (Population–Concept–Context) framework, conducting systematic searches in multiple mainstream databases, and strictly adhering to the PRISMA-ScR guidelines for literature screening, data extraction, and results reporting. Results The expected results will reveal the temporal evolution trends of endurance research (e.g., a significant increase in the number of related studies after 2017), the distribution characteristics of research subjects (differences between elite and amateur runners), and the high diversity of measurement protocols and indicators used in different studies. Conclusion This review will highlight the inconsistencies in terminology and operational definitions in current durability research and identify key knowledge gaps in the field regarding research subjects, measurement methods, and mechanistic explanations.