Effects of thermal stress on human performance
Swedish Defence Research Establishment, Karlstad, Sweden.Scandinavian Journal of Work, Environment & Health (Impact Factor: 3.45). 02/1989; 15 Suppl 1:27-33.
Experimental evidence indicates that even relatively mild thermal stress may affect human performance. Tasks requiring manual dexterity and muscular strength are clearly impaired by cold exposure, while decrements in vigilance performance and endurance are well documented effects of heat stress. The considerable variation in results regarding the effects of thermal stress may, to some extent, be attributable to complex interactions between exposure conditions, task characteristics, and individual factors. In the present paper the relevance of some of the earlier research work on heat and cold stress is evaluated in the light of the practical and theoretical implications of more recent findings. Current work regarding the nature and extent of the effects of thermal stress on more complex performance is discussed. Attention is also focused on the significance of individual skill and training experience for performance under unfavorable conditions.
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Article: Effects of thermal stress on human performance
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- "Heat stress can produce detrimental effects on motor response, and since most cognitive tasks require a motor response, some cognitive deficiencies may be attributed to decreased motor perform- ance. The association between t core (and/or its rate of change) and performance loss thus appears to be theoretically well established[11,12]and corroborated by several experimental studies151617. The skin temperature is also widely recognized as playing a significant role in performance loss. "
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- "Temperature dependency in motor skill learning, , 4 Wilby (1995) reported improvements in shooting performance with forearm cooling. These 1 equivocal effects might be explained by differences in the intensity and length of thermal 2 exposure across experimental conditions (Hancock, Ross, & Szalma, 2007; Pilcher, Nadler, & 3 Busch, 2002; Enander, 1989). The likelihood that performance will be degraded depends on the 4 extent to which temperature conditions form a thermal stressor, in terms of deviation from some 5 optimal-level of function or comfort. "
ABSTRACT: The present study investigated the role of temperature as a contextual condition for motor skill learning. Precision grip task training occurred while forearm cutaneous temperature was either heated (40-45 °C) or cooled (10-15 °C). At test, temperature was either reinstated or changed. Performance was comparable between training conditions while at test, temperature changes decreased accuracy, especially after hot training conditions. After cold training, temperature change deficits were only evident when concurrent force feedback was presented. These findings are the first evidence of localized temperature dependency in motor skill learning in humans. Results are not entirely accounted for by a context-dependent memory explanation and appear to represent an interaction of neuromuscular and sensory processes with the temperature present during training and test.