Moran Daniel S, Pandolf Kent B, Heled Yuval, Gonzalez Richard R
Heller Institute of Medical Research, Sheba Medical Center Tel Hashomer 52621, Israel.
J Basic Clin Physiol Pharmacol. 2003;14(1):17-30. doi: 10.1515/jbcpp.2003.14.1.17.
The purpose of this study was to develop guidelines based on the previously described environmental stress index (ESI) and physiological strain index (PSI) for work-rest cycles (WRC) during training, especially in the military. The ESI was introduced as a potential substitute for the Wet Bulb Globe Temperature Index because of the very high correlation coefficients between them. The ESI is constructed from the fast-reading meteorological response sensors ambient temperature (Ta), relative humidity (RH), and global radiation (GR), which require only a few seconds to reach equilibrium. The ESI, the first stress index using direct measurements of solar radiation (SR), is calculated as follows: ESI = 0.63Ta - 0.03RH + 0.002SR + 0.0054 (Ta x RH) - 0.073(0.1 + SR)(-1). The PSI is based on heart rate (HR) and rectal temperature (Tre) and can indicate heat strain online and analyze databases. The PSI is constructed as follows: PSI = 5(Tret - Tre0) x (39.5 - Tre0)(-1) + 5(HRt - HR0) x (180 - HR0)(-1), where Tre0 and HR0 are the initial Tre and HR, and Tret and HRt are simultaneous measurements taken at any time. The PSI is scaled from 0 to 10, whereby the respective variables, PSIHR and PSITre, representing the cardiovascular and thermoregulation systems, can contribute up to five units to the overall strain assessment. To integrate the PSI and ESI, we decided to use only the PSIHR component, which represents the metabolic rate and the strain reflected by the cardiovascular system. Furthermore, PSIHR is easier to measure, is easier to implement, and simplifies the integration with ESI. Concomitantly, PSIHR categorizes the strain between 0 and 5, the higher the value, the higher the strain. We believe that the use of the PSI WRC values will help in decreasing the risk of future heat injuries.
本研究的目的是基于先前描述的环境压力指数（ESI）和生理应变指数（PSI）制定训练期间工作-休息周期（WRC）的指南，特别是在军事领域。由于ESI与湿球黑球温度指数之间的相关系数非常高，因此引入ESI作为其潜在替代指标。ESI由快速读取的气象响应传感器测量的环境温度（Ta）、相对湿度（RH）和全球辐射（GR）构建而成，这些传感器只需几秒钟就能达到平衡。ESI是首个使用太阳辐射（SR）直接测量值的压力指数，其计算方法如下：ESI = 0.63Ta - 0.03RH + 0.002SR + 0.0054（Ta×RH） - 0.073（0.1 + SR）（-1）。PSI基于心率（HR）和直肠温度（Tre），可在线指示热应激并分析数据库。PSI的构建方法如下：PSI = 5（Tret - Tre0）×（39.5 - Tre0）（-1） + 5（HRt - HR0）×（180 - HR0）（-1），其中Tre0和HR0是初始的Tre和HR，Tret和HRt是在任何时间同时进行的测量值。PSI的范围为0至10，代表心血管和体温调节系统的各个变量，即PSIHR和PSITre，在整体应变评估中最多可贡献五个单位。为了整合PSI和ESI，我们决定仅使用代表代谢率和心血管系统反映的应变的PSIHR组件。此外，PSIHR更易于测量、更易于实施，并且简化了与ESI的整合。同时，PSIHR将应变分为0至5级，值越高，应变越高。我们认为，使用PSI的WRC值将有助于降低未来热损伤的风险。
