Wittels Harrison L, Wishon Michael Joseph, Davilla Hector, McDonald Samantha M, Temme Leonard A, Wittels S Howard
Tiger Tech Solutions, Inc, Miami Beach, FL 33140, United States.
U.S. Army Aeromedical Research Laboratory, Fort Novosel, AL 36362, United States.
Mil Med. 2025 Jun 13. doi: 10.1093/milmed/usaf295.
Warfighters perform highly complex and dangerous combat missions are both physically and cognitively challenging. Meeting these physiological demands are regulated by the autonomic nervous system (ANS). Thus, continuously monitoring ANS activity during combat and training may critically inform military leadership of the current physiological state and ability of their warfighters to effectively execute mission tasks. The purpose of this study was to quantify ANS response throughout 540 minutes (9 hours) of aviation-related combat training drills performed in the UH-60 helicopter.
Aircrew members recruited from the United States Army Aeromedical Research Laboratory participated in the current study. ANS function was measured using the Warfighter Monitor (WFM, Tiger Tech Solutions, Inc., Miami, FL, Unites States), an armband monitor equipped with electrocardiographic capabilities. Subjects wore the WFM on the upper arm throughout their 540-minute combat training which consisted of aviation-related tasks. The WFM continuously monitored heart rate (HR), HR variability (HRV), and respiration rate (RR). Two HRV time-domain metrics were calculated: SD of the NN interval (SDNN) and the root mean square of successive differences of NN intervals (rMSSD). Studentized t-tests were performed to evaluate within- and between-group differences in ANS activity.
Thirty-four healthy, aircrew members aged between 18 and 45 years and mostly male, participated in the current study. For pre-flight events, average HRs ranged between 76.1 and 91.2 bpm. On average, HRs increased between +10.2 and +12.9 bpm. HRV metrics were between 72.4 and 91.3 milliseconds for rMSSD and from 101.8-139.9 ms for SDNN. RRs for aircrew members ranged between 12.4 and 13.5 breaths/min and increased by +1.4 to +1.7 breaths/min. For in-flight operations, significantly higher HRs (88.2-100.2 bpm) were observed. Similarly, significantly different increases were reported (+14.7 to +26.4 bpm). HRV metrics were significantly lower (rMSSD: 62.8-83.7 milliseconds; SDNN: 93.8-116.7 milliseconds). The average and increases in RRs were significantly higher, 12.8-17.3 breaths/min and +1.5 to +4.2 breaths/min.
Significant increases in sympathetic drive were observed in U.S. warfighter aircrew during combat mission training, reflected by higher HRs, RRs, and lower HRV. The magnitudes in the ANS response, however, differed between pre- and in-flight operations with the latter inducing a larger response, possibly attributed to greater physical and cognitive workloads. These observations may aid warfighters and military leadership in designing effective preparedness training and implementing immediate intervention for managing the heightened sympathetic drive while preventing negative outcomes.
执行高度复杂且危险的战斗任务的作战人员面临着身体和认知上的挑战。满足这些生理需求由自主神经系统（ANS）调节。因此，在战斗和训练期间持续监测ANS活动可能会让军事领导层至关重要地了解其作战人员当前的生理状态以及有效执行任务的能力。本研究的目的是量化在UH - 60直升机上进行的540分钟（9小时）与航空相关的战斗训练演习中ANS的反应。
从美国陆军航空医学研究实验室招募的机组人员参与了本研究。使用战士监测仪（WFM，Tiger Tech Solutions公司，迈阿密，佛罗里达州，美国）测量ANS功能，这是一种配备心电图功能的臂带式监测仪。在整个540分钟的战斗训练中，受试者将WFM佩戴在上臂，训练包括与航空相关的任务。WFM持续监测心率（HR）、心率变异性（HRV）和呼吸频率（RR）。计算了两个HRV时域指标：NN间期标准差（SDNN）和NN间期连续差值的均方根（rMSSD）。进行学生化t检验以评估ANS活动在组内和组间的差异。
34名年龄在18至45岁之间、大多为男性的健康机组人员参与了本研究。对于飞行前阶段，平均心率在76.1至91.2次/分钟之间。平均而言，心率增加了10.2至12.9次/分钟。rMSSD的HRV指标在72.4至91.3毫秒之间，SDNN在101.8 - 139.9毫秒之间。机组人员的RR在12.4至13.5次/分钟之间，增加了1.4至1.7次/分钟。对于飞行中操作，观察到显著更高的心率（88.2 - 100.2次/分钟）。同样，报告的显著不同的增加幅度为14.7至26.4次/分钟。HRV指标显著更低（rMSSD：62.8 - 83.7毫秒；SDNN：93.8 - 116.7毫秒）。RR的平均值和增加幅度显著更高，为12.8 - 17.3次/分钟和1.5至4.2次/分钟。
在美国作战人员机组人员的战斗任务训练期间观察到交感神经驱动显著增加，表现为更高的心率、呼吸频率和更低的心率变异性。然而，ANS反应的幅度在飞行前和飞行中操作之间有所不同，后者引发的反应更大，这可能归因于更大的身体和认知工作量。这些观察结果可能有助于作战人员和军事领导层设计有效的准备训练，并实施即时干预以管理增强的交感神经驱动，同时防止负面结果。
