Biophysics and Biomedical Modeling Division, United States Army Research Institute of Environmental Medicine , Natick, Massachusetts.
J Appl Physiol (1985). 2018 Feb 1;124(2):432-441. doi: 10.1152/japplphysiol.00353.2017. Epub 2017 Aug 10.
Safe performance limits of soldiers and athletes have typically relied on predictive work-rest models of ambient conditions, average work intensity, and characteristics of the population. Bioengineering advances in noninvasive sensor technologies, including miniaturization, reduced cost, power requirements, and comfort, now make it possible to produce individual predictions of safe thermal-work limits. These precision medicine assessments depend on the development of thoughtful algorithms based on physics and physiology. Both physiological telemetry and thermal-strain indexes have been available for >50 years, but greater computing power and better wearable sensors now make it possible to provide actionable information at the individual level. Core temperature can be practically estimated from time series heart rate data and, using an adaptive physiological strain index, provides meaningful predictions of safe work limits that cannot be predicted from only core temperature or heart rate measurements. Early adopters of this technology include specialized occupations where individuals operate in complete encapsulation such as chemical protective suits. Emerging technologies that focus on heat flux measurements at the skin show even greater potential for estimating thermal-work strain using a parsimonious sensor set. Applications of these wearable technologies include many sports and military training venues where inexperienced individuals can learn effective work pacing strategies and train to safe personal limits. The same strategies can also provide a technologically based performance edge for experienced workers and athletes faced with novel and nonintuitive physiological challenges, such as health care providers in full protective clothing treating Ebola patients in West Africa in 2014. NEW & NOTEWORTHY This mini-review details how the application of computational techniques borrowed from signal processing and control theory can provide meaningful advances for the applied physiological problem of real-time thermal-work strain monitoring. The work examines the development of practical core body temperature estimation techniques and how these can be used in combination with current and updated thermal-work strain indexes to provide objective state assessments and to optimize work rest schedules for a given task.
士兵和运动员的安全性能极限通常依赖于环境条件、平均工作强度和人群特征的预测性工作-休息模型。非侵入式传感器技术的生物工程进展，包括小型化、降低成本、功耗和舒适度，现在使得对安全热工作极限进行个体预测成为可能。这些精准医学评估依赖于基于物理和生理学的深思熟虑算法的开发。生理遥测和热应变指标已经存在了 50 多年，但更强的计算能力和更好的可穿戴传感器现在使得在个体层面提供可操作信息成为可能。核心体温可以从心率时间序列数据中实际估计，并且使用自适应生理应变指标，可以提供无法仅从核心体温或心率测量预测的安全工作极限的有意义预测。这项技术的早期采用者包括那些个体在完全封装中操作的特殊职业，如化学防护服。专注于皮肤热通量测量的新兴技术显示出使用简约传感器组估计热工作应变的更大潜力。这些可穿戴技术的应用包括许多运动和军事训练场所，在这些场所，没有经验的个体可以学习有效的工作节奏策略，并根据个人安全极限进行训练。同样的策略也可以为面临新颖且非直观的生理挑战的经验丰富的工人和运动员提供基于技术的性能优势，例如 2014 年在西非穿着全套防护服治疗埃博拉患者的医疗保健提供者。
新的和值得注意的是，这篇小型综述详细介绍了如何应用从信号处理和控制理论借来的计算技术，为实时热工作应变监测的应用生理问题提供有意义的进展。这项工作检查了实用核心体温估计技术的发展，以及如何将这些技术与当前和更新的热工作应变指标结合使用，为给定任务提供客观的状态评估，并优化工作休息时间表。
