Bass, David Eli2016-11-142016-11-1419531953https://hdl.handle.net/2144/19078Thesis (Ph.D.)--Boston UniversityWhen an individual is abruptly exposed to heat, he can work only with great difficulty. Tasks which ordinarily are performed with ease are frequently impossible to complete due to dangerously high body temperature and cardiovascular inadequacy. Within several days a given task can be performed with little discomfort. This improved ability to work in the heat is commonly termed "acclimatization to heat", and is accompanied by several well-defined physiological adaptations - the so-called "indices" of heat acclimatization. These are: (a) lower skin and rectal temperatures during work; (b) lower heart rate during work; (c) increased cardiovascular stability with changing posture; (d) increased sweat rate during work, and (e) decreased metabolic cost for a given task, (i.e., greater efficiency). The process of acclimatization to heat can be considered as a physiological entity possessing the following oharacteristics: (a) It occurs rapidly (4-7 days); (b) it can be induced by short, intermittent exposures; (c) it is enhanced by exercise and good physical condition; (d) it is retarded by inadequate salt and water intakes; (e) it is largely retained during periods of up to four weeks of no heat stress; (f) acclimatization to a given heat load confers complete acclimatization to lesser loads and partial acclimatization to higher ones. [TRUNCATED]en-USBased on investigation of the BU Libraries' staff, this work is free of known copyright restrictions.Thesis/Dissertation