Introduction Hyperthermia during exercise induces central and peripheral fatigue and impairs physical performance. To facilitate heat loss and optimize performance, athletes can hasten body cooling prior (pre‐cooling) or during (per‐cooling) exercise. However, it is unclear whether per‐cooling effect is the same on ‘aerobic’ and ‘anaerobic’ types of exercise (duration <75 and >76 seconds, respectively, according to Gastin [Sports Med 2001;31:725‐741]) and whether the body area that is cooled makes a difference. Methods A literature search led to the identification of 1582 potential studies. Included studies had to include physical exercise with sufficient details on the type, duration, intensity, and provide valid performance measures and a cooling intervention administered during exercise with sufficient details on the type and site of application. Results Forty‐five studies were included. Per‐cooling provides a performance benefit during ‘aerobic’ (standardized mean difference (SMD) of 0.60, P < .001) and ‘anaerobic’ exercises (SMD = 0.27, P < .02). The effects were greater during aerobic compared to anaerobic exercises (P < .01). Internal cooling (cold fluid ingestion such as cold water and ice slurry/menthol beverage) and external cooling (face, neck, and torso) provide the greatest performance benefit for ‘aerobic’ performance with a moderate to large effect (0.46 < SMD < 1.24). For ‘anaerobic’ exercises, wearing a whole‐body cooling garment is the best way to enhance exercise performance (SMD = 0.39, P < .01). Conclusion Per‐cooling improves ‘aerobic’ and ‘anaerobic’ exercise performance with a greater benefit for ‘aerobic’ exercise. The magnitude of the effect depends on the type and site of the cooling application.

Workers exposed to hot and humid conditions suffer from heat stress that affects their concentration and can potentially lead to an increase in workplace accidents. To minimize heat stress, protective equipment may be worn, such as personal cooling garments. This paper presents and discusses the performances, advantages and disadvantages of existing personal cooling garments, namely air-cooled, liquid-cooled, phase change, hybrid, gas expansion and vacuum desiccant cooling garments, and a thermoelectric cooling technology. The main objective is to identify the cooling technique that would be most suitable for deep mining workers. It appears that no cooling technology currently on the market is perfectly compatible with this type of mining environment. However, combining two or more cooling technologies into a single hybrid system could be the solution to an optimized cooling garment for deep mines.

Research has proven the importance of cooling garments in reducing heat stress, especially for workers in extreme environments. The currently available cooling capacity of these garments should be controlled for improving their efficiency and autonomy. In this study, we investigated the Hexoskin wearable biometric shirt's capacity to monitor heart rate. Twelve male volunteers wore a Hexoskin biometric shirt and Polar® H7 heart rate sensor and they completed two identical tests under two different climate conditions (25˚C ± 0.5˚C; 39% ± 1% relative humidity and 31˚C ± 0.5˚C; 60% ± 1% relative humidity). The results from four different statistical methods show a high correlation and an absence of significant differences between the Polar® and Hexoskin systems in monitoring the subjects' heart rates. The Hexoskin wearable biometric shirt can be used to monitor the heart rate of humans in moderate or hot and humid climates under variable physical activities, regardless of their age, weight or height.

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