Previous studies have indicated that there is no consensus on the effects of extremely low‐frequency electromagnetic (ELF‐EMF) exposure on the cardiovascular system. This study aimed to explore the short‐term effect of ELF‐EMF exposure on heart rate (HR) and HR variability (HRV). The sample consisted of 34 healthy males aged 18–27 years. The participants were randomly assigned to the EMF (n = 17) or the Sham group (n = 17). We employed a double‐blind repeated‐measures design consisting of three 5 min experimental periods. The chest region of each individual in the EMF group was exposed to 50 Hz, 28 μT, linear polarized, continuous EMF during the EMF exposure period. HR and HRV data were recorded continuously by using a photoplethysmography sensor. Within‐subject statistical analysis indicated a significant HR deceleration in both the EMF and Sham groups. However, the standard deviation of the NN intervals (SDNN), root mean square of successive differences (RMSSD), low‐frequency (LF), and high‐frequency (HF) powers increased only in the EMF group and remained stable in the Sham group. We also compared the same HRV indices measured during the EMF and Sham periods between the two experimental groups. The between‐subject analysis results demonstrated significantly higher SDNN, RMSSD, LF, and HF values in the EMF group than in the Sham group. The LF/HF ratio did not change significantly within and between groups. On the basis of these results, we concluded that short‐term exposure of the chest region to ELF‐EMF could potentially enhance parasympathetic predominance during the resting condition. Bioelectromagnetics. 2021;42:60–75. © 2020 Bioelectromagnetics Society.

中文翻译：

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50 Hz 电磁场职业水平对人体心率变异性的短期影响

先前的研究表明，极低频电磁（ELF-EMF）暴露对心血管系统的影响尚未达成共识。本研究旨在探讨 ELF-EMF 暴露对心率 (HR) 和 HR 变异性 (HRV) 的短期影响。样本由 34 名年龄在 18-27 岁之间的健康男性组成。参与者被随机分配到 EMF ( n  = 17) 或假组 ( n = 17）。我们采用了双盲重复测量设计，包括三个 5 分钟的实验期。在 EMF 暴露期间，EMF 组中每个个体的胸部区域都暴露于 50 Hz、28 μT、线性极化、连续的 EMF。HR 和 HRV 数据通过使用光电容积描记传感器连续记录。受试者内统计分析表明 EMF 和假手术组的 HR 均显着减慢。然而，NN 区间的标准偏差 (SDNN)、逐次差分的均方根 (RMSSD)、低频 (LF) 和高频 (HF) 功率仅在 EMF 组中增加，而在假手术组中保持稳定团体。我们还比较了两个实验组在 EMF 和假手术期间测量的相同 HRV 指数。受试者间分析结果表明，EMF 组的 SDNN、RMSSD、LF 和 HF 值显着高于 Sham 组。LF/HF 比率在组内和组之间没有显着变化。基于这些结果，我们得出结论，胸部区域短期暴露于 ELF-EMF 可能会增强静息状态下的副交感神经优势。生物电磁学。2021；42:60-75。© 2020 生物电磁学学会。