De Wachter Jonas, Proost Matthias, Habay Jelle, Verstraelen Matthias, Díaz-García Jesús, Hurst Philip, Meeusen Romain, Van Cutsem Jeroen, Roelands Bart
Human Physiology and Sports Physiotherapy Research Group, Vrije Universiteit Brussel, Brussels, Belgium.
Faculty of Sport Sciences, University of Extremadura, Caceres, Spain.
Front Physiol. 2021 Oct 26;12:761232. doi: 10.3389/fphys.2021.761232. eCollection 2021.
A myriad of factors underlie pacing-/exhaustion-decisions that are made during whole-body endurance performance. The prefrontal cortex (PFC) is a brain region that is crucial for decision-making, planning, and attention. PFC oxygenation seems to be a mediating factor of performance decisions during endurance performance. Nowadays, there is no general overview summarizing the current knowledge on how PFC oxygenation evolves during whole-body endurance performance and whether this is a determining factor. Three electronic databases were searched for studies related to the assessment of PFC oxygenation, through near-IR spectroscopy (NIRS), during endurance exercise. To express PFC oxygenation, oxygenated (HbO) and deoxygenated hemoglobin (HHb) concentrations were the primary outcome measures. Twenty-eight articles were included. Ten articles focused on assessing prefrontal oxygenation through a maximal incremental test (MIT) and 18 focused on using endurance tasks at workloads ranging from low intensity to supramaximal intensity. In four MIT studies measuring HbO, an increase of HbO was noticed at the respiratory compensation point (RCP), after which it decreased. HbO reached a steady state in the four studies and increased in one study until exhaustion. All studies found a decrease or steady state in HHb from the start until RCP and an increase to exhaustion. In regard to (non-incremental) endurance tasks, a general increase in PFC oxygenation was found while achieving a steady state at vigorous intensities. PCF deoxygenation was evident for near-to-maximal intensities at which an increase in oxygenation and the maintenance of a steady state could not be retained. : MIT studies show the presence of a cerebral oxygenation threshold (ThCox) at RCP. PFC oxygenation increases until the RCP threshold, thereafter, a steady state is reached and HbO declines. This study shows that the results obtained from MIT are transferable to non-incremental endurance exercise. HbO increases during low-intensity and moderate-intensity until vigorous-intensity exercise, and it reaches a steady state in vigorous-intensity exercise. Furthermore, ThCox can be found between vigorous and near-maximal intensities. During endurance exercise at near-maximal intensities, PFC oxygenation increases until the value exceeding this threshold, resulting in a decrease in PFC oxygenation. Future research should aim at maintaining and improving PFC oxygenation to help in improving endurance performance and to examine whether PFC oxygenation has a role in other performance-limiting factors.
在全身耐力运动过程中，有无数因素影响着节奏/疲劳决策。前额叶皮质（PFC）是大脑中对决策、规划和注意力至关重要的区域。PFC氧合似乎是耐力运动中表现决策的一个中介因素。目前，尚无全面综述总结关于PFC氧合在全身耐力运动过程中如何演变以及这是否为一个决定性因素的现有知识。通过检索三个电子数据库，查找与在耐力运动期间通过近红外光谱（NIRS）评估PFC氧合相关的研究。为了表示PFC氧合，主要的结果指标是氧合血红蛋白（HbO）和脱氧血红蛋白（HHb）浓度。纳入了28篇文章。10篇文章侧重于通过最大递增测试（MIT）评估前额叶氧合，18篇文章侧重于使用从低强度到超最大强度的工作负荷下的耐力任务。在四项测量HbO的MIT研究中，发现HbO在呼吸补偿点（RCP）处增加，之后下降。在四项研究中HbO达到稳定状态，在一项研究中直到疲劳时增加。所有研究都发现从开始到RCP，HHb下降或达到稳定状态，并且到疲劳时增加。关于（非递增）耐力任务，发现PFC氧合在剧烈强度下达到稳定状态时总体增加。在接近最大强度时，PFC脱氧明显，此时氧合增加和稳定状态的维持无法保持。：MIT研究表明在RCP处存在脑氧合阈值（ThCox）。PFC氧合增加直到RCP阈值，此后，达到稳定状态且HbO下降。本研究表明从MIT获得的结果可转移到非递增耐力运动。HbO在低强度和中等强度运动期间增加，直到剧烈强度运动，并且在剧烈强度运动中达到稳定状态。此外，ThCox可在剧烈强度和接近最大强度之间找到。在接近最大强度的耐力运动期间，PFC氧合增加直到超过该阈值的值，导致PFC氧合下降。未来的研究应旨在维持和改善PFC氧合，以帮助提高耐力表现，并研究PFC氧合在其他性能限制因素中是否起作用。
