Human heat acclimatization in extremely hot environments: A review

Assessment of indoor thermal comfort temperature and related behavioural adaptations: a systematic review

Thermal comfort is linked to our health, well-being, and productivity. The thermal environment is one of the main factors that influence thermal comfort and, consequently, the productivity of occupants inside buildings. Meanwhile, behavioural adaptation is well known to be the most critical contributor to the adaptive thermal comfort model. This systematic review aims to provide evidence regarding indoor thermal comfort temperature and related behavioural adaptation. Studies published between 2010 and 2022 examining indoor thermal comfort temperature and behavioural adaptations were considered. In this review, the indoor thermal comfort temperature ranges from 15.0 to 33.8 °C. The thermal comfort temperature range varied depending on several factors, such as climatic features, ventilation mode, type of buildings, and age of the study population. Elderly and younger children have distinctive thermal acceptability. Clothing adjustment, fan usage, AC usage, and open window were the most common adaptive behaviour performed. Evidence shows that behavioural adaptations were also influenced by climatic features, ventilation mode, type of buildings, and age of the study population. Building designs should incorporate all factors that affect the thermal comfort of the occupants. Awareness of practical behavioural adaptations is crucial to ensure occupants' optimal thermal comfort.

Comparison of health outcomes from heat-related injuries by National Weather Service reported heat wave days and non-heat wave days - Illinois, 2013-2019

It is predicted that heat waves will increase as climate changes. Related public health interventions have expanded over the past decades but are primarily targeted at health outcomes occurring during heat waves. However, heat adaptation is dynamic and adverse outcomes related to heat injuries occur with moderate increases in temperature throughout the summertime. We analyzed outpatient and inpatient heat related injuries from 2013 to 2019. National Weather Service event summaries were used to characterize reported heat wave days and weather data was linked to individual cases. Despite the higher rate of heat injury on heat wave days, only 12.7% of the 17,662 heat-related injuries diagnosed from 2013 to 2019 occurred during reported heat waves. In addition, the National Weather Service surveillance system monitoring heat related injuries only captured 2.1% of all heat related injuries and 30.6% of heat related deaths. As climate changes and warmer conditions become more common, public health response to moderate increases in temperature during summertime needs to be strengthened as do the surveillance systems used to monitor adverse heat related health events. Improved surveillance systems, long-term interventions and strategies addressing climate change may help mitigate adverse health outcomes attributable to heat related injuries over the summertime.

Effect of Handgrip Training in Extreme Heat on the Development of Handgrip Maximal Isometric Strength among Young Males

The aim of this study was to evaluate the acute and adaptive effects of passive extreme heat (100 ± 3 °C) exposition in combination with a strength training protocol on maximal isometric handgrip strength. Fifty-four untrained male university students participated in this investigation. Twenty-nine formed the control group (NG) and 25 the heat-exposed group (HG). All the participants performed a 3-week isotonic handgrip strength training program twice a week with a training volume of 10 series of 10 repetitions with 45-s rest between series, per session. All the subjects only trained their right hand, leaving their left hand untrained. HG performed the same training protocol in hot (100 ± 3 °C) conditions in a dry sauna. Maximal isometric handgrip strength was evaluated each training day before and after the session. NG participants did not experience any modifications in either hand by the end of the study while HG increased maximal strength values in both hands (p < 0.05), decreased the difference between hands (p < 0.05), and recorded higher values than the controls in the trained (p < 0.05) and untrained (p < 0.01) hands after the intervention period. These changes were not accompanied by any modification in body composition in either group. The performance of a unilateral isotonic handgrip strength program in hot conditions during the three weeks induced an increase in maximal isometric handgrip strength in both hands without modifications to bodyweight or absolute body composition.