Toward a record-eligible sub-2-hour marathon: an updated integrative framework of Physiological, technological, and...

Breaking the sub-2-hour marathon barrier under record-eligible conditions requires the coordinated contribution of physiological, biomechanical, psychological, environmental, nutritional, and technological factors. Achieving such a feat demands aerobic power (VO₂_max ≈ 75-85 mL·kg⁻¹·min⁻¹), running economy (≤ 190 mL·kg⁻¹·km⁻¹ at 21 km·h⁻¹), fractional utilization (90-94% VO₂_max, near the maximum metabolic steady state), favourable anthropometry (e.g., low body mass), efficient neuromuscular coordination, and cognitive endurance to sustain near-threshold effort for ~ 2 h. Technological innovations, particularly carbon-fiber-plated footwear ("supershoes") together with refined pacing strategies, optimized nutrition (carbohydrate intake ~ 60-100 g·h⁻¹; caffeine 3-6 mg·kg⁻¹), and advantageous environmental conditions (~ 10 °C, < 60% RH, low wind) have further narrowed the remaining gap. This narrative review extends previous integrative perspectives by incorporating recent advances in thermoregulation, emerging AI-assisted training applications, and cognitive performance into a conceptual systems-oriented perspective on the determinants of record-eligible sub-2-hour marathon performance. It synthesizes multidisciplinary evidence to propose a conceptual model illustrating how physiological, mechanical, cognitive, and technological domains interact to constrain or enhance endurance capacity. The INEOS 1:59 Challenge (1:59:40) and Kelvin Kiptum's world record (2:00:35) exemplify the proximity of this frontier, while ongoing innovations in real-time monitoring and predictive analytics are expected to refine performance optimization further. Collectively, these developments suggest that achieving an officially ratified sub-2-hour marathon is increasingly plausible, provided that physiological, environmental, and technological systems are co-optimized within ethical and regulatory boundaries.