Thermoregulatory Influence of a Cooling Vest on Hyperthermic Athletes

Abstract Context: Athletic trainers must have sound evidence for the best practices in treating and preventing heat-related emergencies and potentially catastrophic events. Objective: To examine the effectiveness of a superficial cooling vest on core body temperature (Tc) and skin temperature (Tsk) in hypohydrated hyperthermic male participants. Design: A randomized control design with 2 experimental groups. Setting: Participants exercised by completing the heat-stress trial in a hot, humid environment (ambient temperature = 33.1 ± 3.1°C, relative humidity = 55.1 ± 8.9%, wind speed = 2.1 ± 1.1 km/hr) until a Tc of 38.7 ± 0.3°C and a body mass loss of 3.27 ± 0.1% were achieved. Patients or Other Participants: Ten healthy males (age = 25.6 ± 1.6 years, mass = 80.3 ± 13.7 kg). Intervention(s): Recovery in a thermoneutral environment wearing a cooling vest or without wearing a cooling vest until Tc returned to baseline. Main Outcome Measure(s): Rectal Tc, arm Tsk, time to return to baseline Tc, and cooling rate. Results: During the heat-stress trial, Tc significantly increased (3.6%) and, at 30 minutes of recovery, Tc had decreased significantly (2.6%) for both groups. Although not significant, the time for return to baseline Tc was 22.6% faster for the vest group (43.8 ± 15.1 minutes) than for the no-vest group (56.6 ± 18.0 minutes), and the cooling rate for the vest group (0.0298 ± 0.0072°C/min) was not significantly different from the cooling rate for the no-vest group (0.0280 ± 0.0074°C/min). The Tsk during recovery was significantly higher (2.1%) in the vest group than in the no-vest group and was significantly lower (7.1%) at 30 minutes than at 0 minutes for both groups. Conclusions: We do not recommend using the cooling vest to rapidly reduce elevated Tc. Ice-water immersion should remain the standard of care for rapidly cooling severely hyperthermic individuals.

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Athletic Trainers' Attitudes and Perceptions Regarding Exertional Heat Stroke Before and After an Educational Intervention

Athletic Training Education Journal ◽

10.4085/1203179 ◽

2017 ◽

Vol 12 (3) ◽

pp. 179-187 ◽

Cited By ~ 2

Author(s):

Kristen Couper Schellhase ◽

Jennifer Plant ◽

Stephanie M. Mazerolle

Keyword(s):

Educational Intervention ◽

Cold Water ◽

Core Body Temperature ◽

Athletic Trainers ◽

Water Immersion ◽

Heat Stroke ◽

Cold Water Immersion ◽

Attitudes And Perceptions ◽

Before And After ◽

Core Body

Context: Death from exertional heat stroke (EHS) is preventable when evidence-based guidelines are followed. The assessment of core body temperature using rectal thermometry and the treatment of cold-water immersion for EHS has been established as the standard of care; however, rectal thermometry is still controversial. Athletic trainers (ATs) may lack knowledge and comfort with this skill, which could impact implementation. Objective: Examine ATs' current practices, attitudes, and perceptions regarding EHS before and after an educational intervention. Design: Prequantitative/postquantitative experimental. Setting: Classroom. Patients or Other Participants: Twenty-five ATs in various athletic training settings. Intervention(s): Educational intervention designed to increase knowledge and address negative attitudes and perceptions regarding EHS evaluation and treatment. Main Outcome Measure(s): Attitude and perception scores. Results: Prior to the educational intervention, most ATs (86.9%, 20/23) reported that they use methods other than rectal thermometry to evaluate EHS. Of those who did not use rectal thermometry, their reasons included: lack of equipment/budget, concerns about liability/lack of consent (especially when dealing with minors), lack of training, and/or concerns about the privacy, embarrassment, compliance of the athlete. Cold-water immersion was chosen as the definitive method of cooling an athlete by only 41.7% (n = 10) of participants. Following the educational intervention, attitudes toward the use of rectal temperature to assess core body temperature (t[24] = 8.663, P < .001) and cold-water immersion treatment for EHS (t[24] = 4.187, P < .001) were significantly improved. However, while attitudes toward the use of other “cold” methods to treat EHS were not significantly changed (t[24] = 1.684, P = .105), perceptions regarding nonexertional influences on EHS were significantly improved (t[24] = 1.684, P = .105). Conclusions: This study demonstrated that a 3-hour educational intervention can improve attitudes and perceptions regarding the assessment and treatment of EHS in the short term. It is important that educational interventions use best-practice continuing education methods and include special attention to the barriers to evidence-based practice.

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Core body temperature does not cool down with skin surface temperature during recovery at room temperature after acute heat stress exposure

Livestock Science ◽

10.1016/j.livsci.2016.07.010 ◽

2016 ◽

Vol 191 ◽

pp. 143-147 ◽

Cited By ~ 3

Author(s):

A. Sapkota ◽

A. Herr ◽

J.S. Johnson ◽

D.C. Lay

Keyword(s):

Heat Stress ◽

Body Temperature ◽

Surface Temperature ◽

Room Temperature ◽

Core Body Temperature ◽

Skin Surface ◽

Skin Surface Temperature ◽

Stress Exposure ◽

Acute Heat Stress ◽

Core Body

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Genetic parameters for hair characteristics and core body temperature in a multibreed Brahman–Angus herd1

Journal of Animal Science ◽

10.1093/jas/skz188 ◽

2019 ◽

Vol 97 (8) ◽

pp. 3246-3252 ◽

Cited By ~ 3

Author(s):

Kaitlyn M Sarlo Davila ◽

Heather Hamblen ◽

Peter J Hansen ◽

Serdal Dikmen ◽

Pascal A Oltenacu ◽

...

Keyword(s):

Heat Stress ◽

Body Temperature ◽

Genetic Parameters ◽

Core Body Temperature ◽

Cattle Breed ◽

Measuring Device ◽

Hair Samples ◽

Diameter Core ◽

Humidity Index ◽

Core Body

Abstract Thermal stress in hot humid conditions limits cattle production. The objectives for this study were to estimate genetic parameters for hair characteristics and core body temperature under low and high temperature humidity index (THI) conditions. Hair samples were collected and measured for length and diameter. Core body temperature was measured as vaginal temperature every 15 min over a 5-d period using an iButton temperature measuring device implanted in a blank CIDR in 336 heifers from the University of Florida multibreed herd (ranging from 100% Angus to 100% Brahman). Restricted maximum likelihood procedures were used to estimate heritabilities from multiple bivariate animal models using the WOMBAT program. Estimates of heritability for hair diameter, undercoat length, topcoat length, body temperature under low THI conditions, and body temperature under high THI conditions were 0.50, 0.67, 0.42, 0.32, and 0.26, respectively. The genetic parameters estimated in this study indicate a large, exploitable genetic variance which can be selected upon to improve tolerance in cattle. Breed effects for differing compositions of Brahman and Angus were also estimated. As Brahman breed composition increased by 25% undercoat length, topcoat length, body temperature under low THI conditions, and body temperature under high THI conditions decreased by 1.32 mm, 2.94 mm, 0.11 °C, and 0.14 °C, respectively. Under both low and high THI conditions, cattle with 25% Brahman breed composition or greater maintained a significantly lower body temperature than the 100% Angus breed group. The incorporation of Brahman germplasm is recommended for herds that often experience heat stress conditions in order to increase resilience to heat stress.

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Validation of an intramuscularly-implanted microchip and a surface infrared thermometer to estimate core body temperature in broiler chickens exposed to heat stress

Computers and Electronics in Agriculture ◽

10.1016/j.compag.2016.12.010 ◽

2017 ◽

Vol 133 ◽

pp. 1-8 ◽

Cited By ~ 5

Author(s):

O.S. Iyasere ◽

S.A. Edwards ◽

M. Bateson ◽

M. Mitchell ◽

J.H. Guy

Keyword(s):

Heat Stress ◽

Body Temperature ◽

Broiler Chickens ◽

Core Body Temperature ◽

Infrared Thermometer ◽

Core Body

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The effects of heat stress on cognition in persons with multiple sclerosis

Multiple Sclerosis Journal ◽

10.1177/1352458511422926 ◽

2011 ◽

Vol 18 (4) ◽

pp. 489-497 ◽

Cited By ~ 14

Author(s):

P Hämäläinen ◽

A Ikonen ◽

A Romberg ◽

H Helenius ◽

J Ruutiainen

Keyword(s):

Multiple Sclerosis ◽

Heat Stress ◽

Body Temperature ◽

Cognitive Functioning ◽

Cognitive Deficits ◽

Core Body Temperature ◽

Heat Exposure ◽

Heat Sensitivity ◽

Serial Addition ◽

Core Body

Background: Heat sensitivity and cognitive deficits are typical manifestations of multiple sclerosis (MS). Although cognitive deficits are quite well characterized, practically no data exist on the effects of heat on cognitive performances in MS. Objective: To assess the effects of short-term heat stress on cognitive functioning in subjects with MS. Methods: A total of 23 heat-sensitive MS and 19 healthy control (HC) subjects participated. Moderate heat exposure took place in a Finnish sauna. Cognitive functioning was measured with tests of sustained attention and processing speed, the Paced Auditory Serial Addition Test (PASAT 3” and 2”) and the computerized visual vigilance test, before, during and after heat exposure. Results: During the heat exposure, the core body temperature of the MS group rose significantly more ( p = 0.002) than that of the HC group. The heat stress worsened the performance of the MS group in the PASAT 3” ( p = 0.025) but not in the other cognitive measures. The performance in the PASAT 3” was reversed almost to the baseline level only 1- h after the heat exposure. Conclusions: A significant increase in core body temperature during heat stress is associated with a mild and reversible worsening of the PASAT 3” performance, while visual vigilance performance seems to remain almost unaffected.

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