بررسی یک استراتژی مداخله‌ای خنک‌کننده‌ برای کاهش استرین حرارتی ناشی از لباس حفاظتی آتش‌نشانان

Introduction: Protective clothes are among the basic needs of firefighters against their occupational risks. Combination of heat stress effects caused by muscle activation and protective clothing, result in a high level of strain in the regulating system of body temperature. The aim of this study was to evaluate the practical cooling method of hand and forearm immersion in water. Methods: In this study, fourteen professional firefighters were assessed. Each fire fighter wore protective clothing and heart rate, core body temprature and skin temprature were measured in sitting position. Then each subject walked on a treadmill in two 20-min bouts (5 km/h, 7.5% gradient) separated by a 15-min recovery period, during which firefighters were cooled (case) via application of hand and forearm water immersion and remained seated without cooling (control). During exercise and recovery time, firefighters, physiologic parameters (heart rate, core body temperature and mean skin temperature) were measured and recorded every five minutes. Results: The results of marginally modeling of longitudinal responses using generalized estimating equations method showed that paremeters of heart strain (core body temprature, skin temprature and heart rate) were significantly reduced after intervention (p<0.05). Conclusion: In situations that intense fire actions must be faced, the cooling strategy of dipping hands and forearms in water could be considered as an effective and simple method in comparison to other cooling strategies.