O'Connor Fergus K, McGarr Gregory W, McCourt Emma R, Meade Robert D, Kenny Glen P
Human and Environmental Physiology Research Unit, School of Human Kinetics, Faculty of Health Sciences, University of Ottawa, Ottawa, Canada.
Consumer and Clinical Radiation Protection Bureau, Health Canada, Ottawa, Ontario, Canada.
Temperature (Austin). 2024 Sep 11;11(4):318-332. doi: 10.1080/23328940.2024.2394341. eCollection 2024.
While foot immersion and neck cooling have been recommended for protecting heat-vulnerable groups, recent evidence does not support their efficacy for mitigating increases in physiological heat strain in older adults. However, their influence on self-reported environmental symptoms and mood-state remains unclear. Seventeen older adults (nine females, median [interquartile range] age: 72 [69-74]) completed three randomized heat exposures (6-h; 38°C, 35% relative humidity) with no cooling (control), foot immersion to mid-calf in 20°C water for the final 40-min of each hour (foot immersion), or foot immersion with a wet towel (20°C) around the neck (foot immersion with neck cooling). Core temperature, skin temperature, and heart rate areas under the curve (AUC) were assessed as indicators of cumulative physiological strain. Environmental symptom scores (68-item environmental symptoms questionnaire) and mood disturbance (40-item profile of mood states questionnaire) were evaluated at end-heating (adjusted for pre-exposure). Core temperature AUC was not different between conditions ( = 0.418). However, the skin temperature and heart rate AUCs were 11.8°C · h [95% confidence interval: 8.1, 15.5] and 12.5 bpm · h [0.1, 24.8] lower for foot immersion and 16.6°C · h [12.9, 20.3] and 19.6 bpm · h [7.2, 32.0] lower for foot immersion with neck cooling compared to control ( ≤ 0.032). Environmental symptom scores were 0.8-fold [0.6, 1.0] lower for both foot immersion with and without neck cooling, compared to control (both = 0.036). Mood disturbance was not different between conditions (both ≥ 0.275). Foot immersion with and without neck cooling reduces self-reported environmental symptoms in older adults despite having little effect on physiological heat strain.
虽然有人建议通过足部浸泡和颈部冷却来保护易受热影响的人群，但最近的证据并不支持它们在减轻老年人生理热应激增加方面的效果。然而，它们对自我报告的环境症状和情绪状态的影响仍不明确。17名老年人（9名女性，年龄中位数[四分位间距]：72[69 - 74]岁）完成了三次随机热暴露（6小时；38°C，相对湿度35%），分别为无冷却（对照）、每小时最后40分钟将足部浸泡至小腿中部（足部浸泡）、或足部浸泡并在颈部围一条湿毛巾（20°C）（足部浸泡加颈部冷却）。评估核心温度、皮肤温度和心率曲线下面积（AUC）作为累积生理应激的指标。在热暴露结束时（根据暴露前情况进行调整）评估环境症状评分（68项环境症状问卷）和情绪障碍（40项情绪状态剖面图问卷）。不同条件下的核心温度AUC没有差异（P = 0.418）。然而，与对照相比，足部浸泡组的皮肤温度和心率AUC分别低11.8°C·小时[95%置信区间：8.1, 15.5]和12.5次/分钟·小时[0.1, 24.8]，足部浸泡加颈部冷却组分别低16.6°C·小时[12.9, 20.3]和19.6次/分钟·小时[7.2, 32.0]（P≤0.032）。与对照相比，有颈部冷却和无颈部冷却的足部浸泡组的环境症状评分均低0.8倍[0.6, 1.0]（P均 = 0.036）。不同条件下的情绪障碍没有差异（P均≥0.275）。有颈部冷却和无颈部冷却的足部浸泡均可减轻老年人自我报告的环境症状，尽管对生理热应激影响不大。
