To assess the lethal effects of work-induced hyperthermia on exercising animals, untrained rats were run to exhaustion at 5 and 20-26 degrees C or restrained at 41.5 degrees C. An exercise-induced core temperature of 40.4 degrees C represented a base line above which mortalities occurred. With increasing core temperature at exhaustion (between 40.4 and 43 degrees C), mortality increased within ...

BACKGROUND To examine whether short-term, ie, five daily sessions, vigorous dynamic cycling exercise and heat exposure could achieve heat acclimation in trained athletes and the effect of heat acclimation on cutaneous blood flow in the active and nonactive limb. METHODS Fourteen male badminton and table tennis athletes (age = 19.6 ± 1.2 years) were randomized into a heat acclimation (EXP, n =...

This study examined the thermoregulatory and circulatory responses, and exercise performance of trained distance runners during exercise in the heat (31°C) at varying relative humidity (RH). In a randomized order, 11 trained male distance runners performed 5 60 min steady-state runs at a speed eliciting 70% of VO2max in RH of 23, 43, 52, 61 and 71%. This was followed immediately with an increme...

heat stress is a common occupational health hazard at outdoor workplaces especially in a hot-humid climate. overheating of the body can cause a number of problems, including heat rash, heat cramps, dizziness, heat exhaustion, and heat stroke. the present study aimed to assess heat stress indices including di, wbgt, and sw req /phs, as a mean to estimate the heat load on the employees of a petro...

Adequate heat balance is critical to human performance in the heat. If heat balance cannot be maintained, the core temperature increases and body water dehydration leads to exhaustion and limit the performance. Clothing heat transfer properties, thermal insulation and water vapour resistance, modify heat exchange and may indirectly affect performance. Work in protective clothing quickly becomes...

eat is the deadliest of all atmospheric phenomena. From 1979 to 1999, the deaths of 8015 Americans were directly associated with excessive heat exposure (Centers for Disease Control 2002). This toll underestimates heat’s true impact, however, as there is no consensus on what constitutes a “heat-related death,” and death certificates often do not identify when heat has acted as a catalyst in exa...

In this paper, the heat pipe heat exchanger (HPHE) is considered and computational fluid dynamics (CFD) is used to analyze its evaporator’s performance and based on it, will be try to increase the thermal efficiency and to optimize the distribution of fluid flow in this type of heat exchangers. The CFD principles which are made use in this article are effective and appropriate methods that usin...