Department of Public Health and Sport Sciences, University of Exeter Medical School, St Luke's Campus, Exeter, UK.
J Physiol. 2024 Sep;602(17):4113-4128. doi: 10.1113/JP284205. Epub 2023 Aug 22.
Endurance exercise performance is known to be closely associated with the three physiological pillars of maximal O uptake ( ), economy or efficiency during submaximal exercise, and the fractional utilisation of (linked to metabolic/lactate threshold phenomena). However, while 'start line' values of these variables are collectively useful in predicting performance in endurance events such as the marathon, it is not widely appreciated that these variables are not static but are prone to significant deterioration as fatiguing endurance exercise proceeds. For example, the 'critical power' (CP), which is a composite of the highest achievable steady-state oxidative metabolic rate and efficiency (O cost per watt), may fall by an average of 10% following 2 h of heavy intensity cycle exercise. Even more striking is that the extent of this deterioration displays appreciable inter-individual variability, with changes in CP ranging from <1% to ∼32%. The mechanistic basis for such differences in fatigue resistance or 'physiological resilience' are not resolved. However, resilience may be important in explaining superlative endurance performance and it has implications for the physiological evaluation of athletes and the design of interventions to enhance performance. This article presents new information concerning the dynamic plasticity of the three 'traditional' physiological variables and argues that physiological resilience should be considered as an additional component, or fourth dimension, in models of endurance exercise performance.
耐力运动表现与最大摄氧量（ ）、次最大运动时的经济性或效率以及（与代谢/乳酸阈现象相关联的）利用率这三个生理支柱密切相关。然而，虽然这些变量的“起跑线”值在预测马拉松等耐力赛事的表现方面具有一定的参考价值，但人们并没有广泛认识到这些变量并非一成不变，而是随着疲劳性耐力运动的进行，容易发生显著恶化。例如，“临界功率”（CP）是最高可实现的稳态氧化代谢率和效率（每瓦特的氧气成本）的综合表现，在进行 2 小时高强度自行车运动后，可能平均下降 10%。更引人注目的是，这种恶化的程度表现出明显的个体间差异，CP 的变化范围从<1%到∼32%不等。对于这种疲劳抵抗力或“生理弹性”差异的机制基础尚未得到解决。然而，弹性在解释卓越的耐力表现方面可能很重要，并且对运动员的生理评估和增强表现的干预措施的设计具有重要意义。本文介绍了有关三个“传统”生理变量的动态可变性的新信息，并认为生理弹性应该被视为耐力运动表现模型的附加组成部分或第四个维度。
