College of Public Health, University of South Florida, USA.
College of Education (Exercise Science), University of South Florida, USA.
Ind Health. 2024 Sep 27;62(5):287-294. doi: 10.2486/indhealth.2024-0015. Epub 2024 Apr 3.
Assigning a value for metabolic rate is central to heat stress assessment. ISO 8996 describes a predictive method for walking based on the American College of Sports Medicine (ACSM) method and another generalized method based on average heart rate. In addition, the US Army uses the load carriage decision aid (LCDA) predictive equation to estimate metabolic rate. The purpose of this study was to assess the accuracy/bias and precision of the ISO heart rate method and the ACSM and LCDA equations. The laboratory database included metabolic rate, heart rate, treadmill speed, and grade during a progressive heat stress protocol. Treadmill speed and grade were set to represent one of three metabolic rates. Accuracy and precision were assessed with Bland-Altman plots. All three methods had good accuracy (low bias). For precision, the ISO heart rate method had a root mean square error (RMSE) of 34 W and 11% when adjusted for repeated measures. The RMSE for two equations was 20 W and 7%. Although the heart method had less accuracy, its application is more generalizable. The heart rate method should be used below the occupational exposure limit for heat stress to avoid a bias toward higher predicted values due to heat strain.
为代谢率赋值是热应激评估的核心。ISO 8996 描述了一种基于美国运动医学学会 (ACSM) 方法的步行预测方法，以及另一种基于平均心率的广义方法。此外，美国陆军使用负荷携带决策辅助 (LCDA) 预测方程来估计代谢率。本研究旨在评估 ISO 心率法和 ACSM 和 LCDA 方程的准确性/偏差和精密度。实验室数据库包括代谢率、心率、跑步机速度和在渐进热应激方案中的坡度。跑步机速度和坡度设置为代表三种代谢率之一。使用 Bland-Altman 图评估准确性和精密度。所有三种方法的准确性都很好（偏差低）。对于精密度，ISO 心率法在调整重复测量后具有 34 W 的均方根误差 (RMSE) 和 11%。两个方程的 RMSE 为 20 W 和 7%。尽管心率法的准确性较低，但它的应用更具普遍性。应在职业暴露极限以下使用心率法来避免由于热应激而导致预测值偏高的偏差。
