scholarly journals Core Temperature Responses in Elite Cricket Players during Australian Summer Conditions

Sports ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 164
Author(s):  
Sharon Stay ◽  
Michelle Cort ◽  
David Ward ◽  
Alex Kountouris ◽  
John Orchard ◽  
...  
Keyword(s):  
Core Temperature ◽  
Air Temperature ◽  
Perceived Exertion ◽  
Wet Bulb Globe Temperature ◽  
Exertional Heat Illness ◽  
Increased Risk ◽  
Globe Temperature ◽  
Temperature Responses ◽  
Breaks In Play ◽  
Australian Summer

This study aimed to observe core temperature responses in elite cricket players under match conditions during the summer in Australia. Thirty-eight Australian male cricketers ingested capsule temperature sensors during six four-day first-class matches between February 2016 and March 2017. Core temperature (Tc) was recorded during breaks in play. Batters showed an increase in Tc related to time spent batting of approximately 1 °C per two hours of play (p < 0.001). Increases in rate of perceived exertion (RPE) in batters correlated with smaller elevations in Tc (0.2 °C per one unit of elevation in RPE) (p < 0.001). Significant, but clinically trivial, increases in Tc of batters were found related to the day of play, wet bulb globe temperature (WBGT), air temperature, and humidity. A trivial increase in Tc (p < 0.001) was associated with time in the field and RPE when fielding. There was no association between Tc and WBGT, air temperature, humidity, or day of play in fielders. This study demonstrates that batters have greater rises in Tc than other cricket participants, and may have an increased risk of exertional heat illness, despite exposure to similar environmental conditions.

scholarly journals Heat Stress Management in the Military: Wet-Bulb Globe Temperature Offsets for Modern Body Armor Systems

2021 ◽  
pp. 001872082110052
Author(s):  
Andrew P. Hunt ◽  
Adam W. Potter ◽  
Denise M. Linnane ◽  
Xiaojiang Xu ◽  
Mark J. Patterson ◽  
...  
Keyword(s):  
Core Temperature ◽  
Environmental Conditions ◽  
Body Armor ◽  
Body Core Temperature ◽  
Wet Bulb Globe Temperature ◽  
Exertional Heat Illness ◽  
Ballistic Protection ◽  
Body Core ◽  
Heavy Work ◽  
Globe Temperature

Objective The aim of this study was to model the effect of body armor coverage on body core temperature elevation and wet-bulb globe temperature (WBGT) offset. Background Heat stress is a critical factor influencing the health and safety of military populations. Work duration limits can be imposed to mitigate the risk of exertional heat illness and are derived based on the environmental conditions (WBGT). Traditionally a 3°C offset to WBGT is recommended when wearing body armor; however, modern body armor systems provide a range of coverage options, which may influence thermal strain imposed on the wearer. Method The biophysical properties of four military clothing ensembles of increasing ballistic protection coverage were measured on a heated sweating manikin in accordance with standard international criteria. Body core temperature elevation during light, moderate, and heavy work was modeled in environmental conditions from 16°C to 34°C WBGT using the heat strain decision aid. Results Increasing ballistic protection resulted in shorter work durations to reach a critical core temperature limit of 38.5°C. Environmental conditions, armor coverage, and work intensity had a significant influence on WBGT offset. Conclusion Contrary to the traditional recommendation, the required WBGT offset was >3°C in temperate conditions (<27°C WBGT), particularly for moderate and heavy work. In contrast, a lower WBGT offset could be applied during light work and moderate work in low levels of coverage. Application Correct WBGT offsets are important for enabling adequate risk management strategies for mitigating risks of exertional heat illness.

Limiting the Rise in Core Temperature During a Rugby Sevens Warm-Up With an Ice Vest

2019 ◽  
Vol 14 (9) ◽  
pp. 1212-1218 ◽  
Author(s):  
Lee Taylor ◽  
Christopher J. Stevens ◽  
Heidi R. Thornton ◽  
Nick Poulos ◽  
Bryna C.R. Chrismas
Keyword(s):  
Core Temperature ◽  
Effect Size ◽  
Perceived Exertion ◽  
Thermal Sensation ◽  
Experimental Period ◽  
Rating Of Perceived Exertion ◽  
Warm Up ◽  
Wet Bulb Globe Temperature ◽  
Before And After ◽  
Globe Temperature

Purpose: To determine how a cooling vest worn during a warm-up could influence selected performance (countermovement jump [CMJ]), physical (global positioning system [GPS] metrics), and psychophysiological (body temperature and perceptual) variables. Methods: In a randomized, crossover design, 12 elite male World Rugby Sevens Series athletes completed an outdoor (wet bulb globe temperature 23–27°C) match-specific externally valid 30-min warm-up wearing a phase-change cooling vest (VEST) and without (CONTROL), on separate occasions 7 d apart. CMJ was assessed before and after the warm-up, with GPS indices and heart rate monitored during the warm-ups, while core temperature (Tc; ingestible telemetric pill; n = 6) was recorded throughout the experimental period. Measures of thermal sensation (TS) and thermal comfort (TC) was obtained pre-warm-up and post-warm-up, with rating of perceived exertion (RPE) taken post-warm-ups. Results: Athletes in VEST had a lower ΔTc (mean [SD]: VEST = 1.3°C [0.1°C]; CONTROL = 2.0°C [0.2°C]) from pre-warm-up to post-warm-up (effect size; ±90% confidence limit: −1.54; ±0.62) and Tc peak (mean [SD]: VEST = 37.8°C [0.3°C]; CONTROL = 38.5°C [0.3°C]) at the end of the warm-up (−1.59; ±0.64) compared with CONTROL. Athletes in VEST demonstrated a decrease in ΔTS (−1.59; ±0.72) and ΔTC (−1.63; ±0.73) pre-warm-up to post-warm-up, with a lower RPE post-warm-up (−1.01; ±0.46) than CONTROL. Changes in CMJ and GPS indices were trivial between conditions (effect size < 0.2). Conclusions: Wearing the vest prior to and during a warm-up can elicit favorable alterations in physiological (Tc) and perceptual (TS, TC, and RPE) warm-up responses, without compromising the utilized warm-up characteristics or physical-performance measures.

scholarly journals Thermal Performance of Single-Story Air-Welled Terraced House in Malaysia: A Field Measurement Approach

2020 ◽  
Vol 13 (1) ◽  
pp. 201
Author(s):  
Pau Chung Leng ◽  
Gabriel Hoh Teck Ling ◽  
Mohd Hamdan Ahmad ◽  
Dilshan Remaz Ossen ◽  
Eeydzah Aminudin ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Air Temperature ◽  
Thermal Performance ◽  
Field Measurement ◽  
Natural Ventilation ◽  
Residential Buildings ◽  
Wet Bulb Globe Temperature ◽  
Natural Lighting ◽  
Ventilation Performance ◽  
Globe Temperature

The provision requirement of 10% openings of the total floor area stated in the Uniform Building By-Law 1984 Malaysia is essential for natural lighting and ventilation purposes. However, focusing on natural ventilation, the effectiveness of thermal performance in landed residential buildings has never been empirically measured and proven, as most of the research emphasized simulation modeling lacking sufficient empirical validation. Therefore, this paper drawing on field measurement investigates natural ventilation performance in terraced housing with an air-well system. The key concern as to what extent the current air-well system serving as a ventilator is effective to provide better thermal performance is to be addressed. By adopting an existing single-story air-welled terrace house, indoor environmental conditions and thermal performance were monitored and measured using HOBO U12 air temperature and humidity, the HOBO U12 anemometer, and the Delta Ohm HD32.3 Wet Bulb Globe Temperature meter for a six-month duration. The results show that the air temperature of the air well ranged from 27.48 °C to 30.92 °C, with a mean relative humidity of 72.67% to 79.25%. The mean air temperature for a test room (single-sided ventilation room) ranged from 28.04 °C to 30.92 °C, with a relative humidity of 70.16% to 76.00%. These empirical findings are of importance, offering novel policy insights and suggestions. Since the minimum provision of 10% openings has been revealed to be less effective to provide desirable thermal performance and comfort, mandatory compliance with and the necessity of the bylaw requirement should be revisited.

scholarly journals Identifying the need for locally-observed wet bulb globe temperature across outdoor athletic venues for current and future climates in a desert environment

2021 ◽  
Author(s):  
Haven Guyer ◽  
Matei Georgescu ◽  
David M Hondula ◽  
Floris Wardenaar ◽  
Jennifer Vanos
Keyword(s):  
Climate Projections ◽  
Design Strategies ◽  
Local Cooling ◽  
Wet Bulb Globe Temperature ◽  
Exertional Heat Illness ◽  
Cooling Design ◽  
Weather Stations ◽  
Globe Temperature ◽  
Sports Venues ◽  
Projected Changes

Abstract Exertional heat illness and stroke are serious concerns across youth and college sports programs. While some teams and governing bodies have adopted the wet bulb globe temperature (WBGT), few practitioners use measurements on the field of play; rather, they often rely on regionally modeled or estimated WBGT. However, urban development-induced heat and projected climate change increase exposure to heat. We examined WBGT levels between various athletic surfaces and regional weather stations under current and projected climates and in hot-humid and hot-dry weather regimes in the southwest U.S. in Tempe, Arizona. On-site sun-exposed WBGT data across five days (07:00–19:00 local time) in June (dry) and August (humid) were collected over five athletic surfaces: rubber, artificial turf, clay, grass, and asphalt. Weather stations data were used to estimate regional WBGT (via the Liljegren model) and compared to on-site, observed WBGT. Finally, projected changes to WBGT were modeled under mid-century and late-century conditions. On-field WBGT observations were, on average, significantly higher than WBGT estimated from regional weather stations by 2.4°C–2.5°C, with mean on-field WBGT across both months of 28.52.76°C (versus 25.83.21°C regionally). However, between-athletic surface WBGT differences were largely insignificant. Significantly higher mean WBGTs occurred in August (30.12.35°C) versus June (26.92.19°C) across all venues; August conditions reached ‘limit activity’ or ‘cancellation’ thresholds for 6–8 hours and 2–4 hours of the day, respectively, for all sports venues. Climate projections show increased WBGTs across measurement locations, dependent on projection and period, with average August WBGT under the highest representative concentration pathway causing all-day activity cancellations. Practitioners are encouraged to use WBGT devices within the vicinity of the fields of play, yet should not rely on weather station estimations without corrections used. Heat concerns are expected to increase in the future, underlining the need for athlete monitoring, local cooling design strategies, and heat adaptation for safety.

scholarly journals Core temperature up to 41.5ºC during the UCI Road Cycling World Championships in the heat

2018 ◽  
Vol 53 (7) ◽  
pp. 426-429 ◽  
Author(s):  
Sebastien Racinais ◽  
Sebastien Moussay ◽  
David Nichols ◽  
Gavin Travers ◽  
Taoufik Belfekih ◽  
...  
Keyword(s):  
Heart Rate ◽  
Core Temperature ◽  
Power Output ◽  
Temperature Response ◽  
Time Trial ◽  
Ambient Conditions ◽  
Wet Bulb Globe Temperature ◽  
Road Cycling ◽  
Road Race ◽  
Globe Temperature

ObjectiveTo characterise the core temperature response and power output profile of elite male and female cyclists during the 2016 UCI Road World Championships. This may contribute to formulating environmental heat stress policies.MethodsCore temperature was recorded via an ingestible capsule in 10, 15 and 15 cyclists during the team time trial (TTT), individual time trial (ITT) and road race (RR), respectively. Power output and heart rate were extracted from individual cycling computers. Ambient conditions in direct sunlight were hot (37°C±3°C) but dry (25%±16% relative humidity), corresponding to a wet-bulb globe temperature of 27°C±2°C.ResultsCore temperature increased during all races (p<0.001), reaching higher peak values in TTT (39.8°C±0.9°C) and ITT (39.8°C±0.4°C), relative to RR (39.2°C±0.4°C, p<0.001). The highest temperature recorded was 41.5°C (TTT). Power output was significantly higher during TTT (4.7±0.3 W/kg) and ITT (4.9±0.5 W/kg) than RR (2.7±0.4 W/kg, p<0.001). Heart rate increased during the TTs (p<0.001) while power output decreased (p<0.001).Conclusion85% of the cyclists participating in the study (ie, 34 of 40) reached a core temperature of at least 39°C with 25% (ie, 10 of 40) exceeding 40°C. Higher core temperatures were reached during the time trials than the RR.

scholarly journals Exertional Heat Illness in American Football Players: When Is the Risk Greatest?

2016 ◽  
Vol 51 (8) ◽  
pp. 593-600 ◽  
Author(s):  
Earl R. Cooper ◽  
Michael S. Ferrara ◽  
Douglas J. Casa ◽  
John W. Powell ◽  
Steven P. Broglio ◽  
...  
Keyword(s):  
Incidence Rate ◽  
Sports Medicine ◽  
National Collegiate Athletic Association ◽  
The United States ◽  
American Football ◽  
Football Players ◽  
Heat Illness ◽  
Wet Bulb Globe Temperature ◽  
Exertional Heat Illness ◽  
Globe Temperature

Context: Knowledge about the specific environmental and practice risks to participants in American intercollegiate football during preseason practices is limited. Identifying risks may mitigate occurrences of exertional heat illness (EHI). Objective: To evaluate the associations among preseason practice day, session number, and wet bulb globe temperature (WBGT) and the incidence of EHI. Design: Descriptive epidemiology study. Setting: Sixty colleges and universities representing 5 geographic regions of the United States. Patients or Other Participants: National Collegiate Athletic Association football players. Main Outcome Measure(s): Data related to preseason practice day, session number, and WBGT. We measured WBGT every 15 minutes during the practice sessions and used the mean WBGT from each session in the analysis. We recorded the incidence of EHIs and calculated the athlete-exposures (AEs). Results: A total of 553 EHI cases and 365 810 AEs were reported for an overall EHI rate of 1.52/1000 AEs (95% confidence interval [CI] = 1.42, 1.68). Approximately 74% (n = 407) of the reported EHI cases were exertional heat cramps (incidence rate = 1.14/1000 AEs; 95% CI = 1.03, 1.25), and about 26% (n = 146) were a combination of exertional heat syncope and heat exhaustion (incidence rate = 0.40/1000 AEs; 95% CI = 0.35, 0.48). The highest rate of EHI occurred during the first 14 days of the preseason period, and the greatest risk was during the first 7 days. The risk of EHI increased substantially when the WBGT was 82.0°F (27.8°C) or greater. Conclusions: We found an increased rate of EHI during the first 14 days of practice, especially during the first 7 days. When the WBGT was greater than 82.0°F (27.8°C), the rate of EHI increased. Sports medicine personnel should take all necessary preventive measures to reduce the EHI risk during the first 14 days of practice and when the environmental conditions are greater than 82.0°F (27.8°C) WBGT.

Collegiate Marching Band Artists Experience High Core Body Temperatures during Rehearsals and Performances

2020 ◽  
Vol 2020 (preprint) ◽  
pp. 0000-0000
Author(s):  
Dawn M. Emerson ◽  
Toni M. Torres-McGehee ◽  
Susan W. Yeargin ◽  
Melani R. Kelly ◽  
Nancy Uriegas ◽  
...  
Keyword(s):  
Risk Factors ◽  
Sweat Rate ◽  
Management Strategies ◽  
Ground Surface ◽  
Urine Specific Gravity ◽  
Marching Band ◽  
Wet Bulb Globe Temperature ◽  
Exertional Heat Illness ◽  
Globe Temperature ◽  
Hydration Characteristics

Abstract Context: No research has investigated thermoregulatory responses and exertional heat illness (EHI) risk factors in marching band (MB) artists performing physical activity in high environmental temperatures. Objective: Examine core temperature (Tc) and EHI risk factors in MB artists. Design: Descriptive epidemiology study. Setting: Three rehearsals and 2 football games for 2 NCAA Division I MBs. Participants: Nineteen volunteers completed the study (female = 13, males = 6; age = 20.5 ± 0.9 years; weight = 75.0 ± 19.1 kg; height = 165.1 ± 7.1 cm). Main Outcome Measures: We measured Tc pre-, post-, and every 15 minutes during activity and recorded wet-bulb globe temperature (WBGT) and relative humidity (RH) every 15 minutes. Other variables included activity time and intensity, ground surface, hydration characteristics (fluid volume, sweat rate, urine specific gravity, percent body mass loss [%BM]), and medical history (eg, previous EHI, medications). Statistical analysis included descriptives (mean ± standard deviation), comparative analyses determined differences within and between days, and linear regression identified variables that significantly explained Tc. Results: Mean rehearsal time = 102.8 ± 19.8 minutes and game time = 260.5 ± 47.7 minutes. Max game Tc (39.1 ± 1.1°C) was significantly higher than rehearsal (38.4 ± 0.7°C, P = .003). The highest max game Tc = 41.2°C. Participants consumed significantly more fluid than their sweat rates (P &lt; .003), which minimized %BM loss, particularly during rehearsals (−0.4 ± 0.6%). Mean game %BM loss = −0.9 ± 2.0%; however, 63.6% of the time, participants reported hypohydrated to game day. Max Tc was significantly predicted by max WBGT, max RH, ground surface, using mental health medications, and hours of sleep (adjusted R2 = 0.542, P &lt; .001). Conclusions: Marching band artists experience high Tc during activity and should have access to athletic trainers who can implement EHI prevention and management strategies.

scholarly journals Effects of two cooling strategies on thermoregulatory responses of tetraplegic athletes during repeated intermittent exercise in the heat

2005 ◽  
Vol 98 (6) ◽  
pp. 2101-2107 ◽  
Author(s):  
N. Webborn ◽  
M. J. Price ◽  
P. C. Castle ◽  
V. L. Goosey-Tolfrey
Keyword(s):  
Core Temperature ◽  
Perceived Exertion ◽  
Thermal Strain ◽  
Heat Strain ◽  
Heat Illness ◽  
Sprint Exercise ◽  
Cooling Strategies ◽  
Thermoregulatory Responses ◽  
Increased Risk ◽  
Cord Injury

Athletes with spinal cord injury (SCI), and in particular tetraplegia, have an increased risk of heat strain and consequently heat illness relative to able-bodied individuals. Strategies that reduce the heat strain during exercise in a hot environment may reduce the risk of heat illness. To test the hypotheses that precooling or cooling during intermittent sprint exercise in a heated environment would attenuate the rise in core temperature in tetraplegic athletes, eight male subjects with SCI (lesions C5–C7; 2 incomplete lesions) undertook four heat stress trials (32.0 ± 0.1°C, 50 ± 0.1% relative humidity). After assessment of baseline thermoregulatory responses at rest for 80 min, subjects performed three intermittent sprint protocols for 28 min. All trials were undertaken on an arm crank ergometer and involved a no-cooling control (Con), 20 min of precooling (Pre), or cooling during exercise (Dur). Trials were administered in a randomized order. After the intermittent sprint protocols, mean core temperature was higher during Con (37.3 ± 0.3°C) compared with Pre and Dur (36.5 ± 0.6°C and 37.0 ± 0.5°C, respectively; P < 0.01). Moreover, perceived exertion was lower during Pre (13 ± 2; P < 0.01) and Dur (12 ± 1; P < 0.01) compared with Con (14 ± 2). These results suggest that both precooling and cooling during intermittent sprint exercise in the heat reduces thermal strain in tetraplegic athletes. The cooling strategies also appear to show reduced perceived exertion at equivalent time points, which may translate into improved functional capacity.

scholarly journals Additional Clothing Increases Heat Load in Elite Female Rugby Sevens Players

2020 ◽  
pp. 1-8
Author(s):  
Mitchell J. Henderson ◽  
Bryna C.R. Chrismas ◽  
Christopher J. Stevens ◽  
Andrew Novak ◽  
Job Fransen ◽  
...  
Keyword(s):  
Heat Load ◽  
Perceived Exertion ◽  
Sweat Rate ◽  
Training Session ◽  
Rating Of Perceived Exertion ◽  
Compression Garments ◽  
Wet Bulb Globe Temperature ◽  
Parallel Group ◽  
Globe Temperature ◽  
Hot Environments

Purpose: To determine whether elite female rugby sevens players are exposed to core temperatures (Tc) during training in the heat that replicate the temperate match demands previously reported and to investigate whether additional clothing worn during a hot training session meaningfully increases the heat load experienced. Methods: A randomized parallel-group study design was employed, with all players completing the same approximately 70-minute training session (27.5°C–34.8°C wet bulb globe temperature) and wearing a standardized training ensemble (synthetic rugby shorts and training tee [control (CON); n = 8]) or additional clothing (standardized training ensemble plus compression garments and full tracksuit [additional clothing (AC); n = 6]). Groupwise differences in Tc, sweat rate, GPS-measured external locomotive output, rating of perceived exertion, and perceptual thermal load were compared. Results: Mean (P = .006, ) and peak (P < .001, ) Tc were higher in AC compared with CON during the training session. There were no differences in external load (F4,9 = 0.155, P = .956, Wilks Λ = 0.935, ) or sweat rate (P = .054, Cohen d = 1.09). A higher rating of perceived exertion (P = .016, Cohen d = 1.49) was observed in AC compared with CON. No exertional-heat-illness symptomology was reported in either group. Conclusions: Player Tc is similar between training performed in hot environments and match play in temperate conditions when involved for >6 minutes. Additional clothing is a viable and effective method to increase heat strain in female rugby sevens players without compromising training specificity or external locomotive capacity.

scholarly journals Thermal comfort models of venue in hot and humid subtropical regions

2021 ◽  
Vol 25 (6 Part A) ◽  
pp. 4225-4231
Author(s):  
Xiaodan Huang ◽  
Qingyuan Zhang ◽  
Xiaoli Ma
Keyword(s):  
Thermal Comfort ◽  
Air Temperature ◽  
Thermal Sensation ◽  
Evaluation Model ◽  
Least Square Method ◽  
Least Square ◽  
Predicted Mean Vote ◽  
Wet Bulb Globe Temperature ◽  
Globe Temperature ◽  
The Relationship

In order to improve the design effect of venues, this paper establishes the evaluation model of indoor thermal comfort for the humid and hot subtropical areas, which provides theoretical reference for venue design. This paper investigates the thermal sensation of basketball players by questionnaire, analyzes the relation-ship between thermal sensation vote and standard effective temperature, predicted mean vote, and wet bulb globe temperature, and develops an index called predicted thermal sensation by using the least square method. The relationship between outdoor air temperature and indoor working temperature under neutral conditions is obtained by measuring data. The results show that the correlation between thermal sensation vote and air temperature is the strongest, R2 is 0.753, while the relationship between thermal sensation vote and air speed is weak, R2 is 0.012. Thermal sensation vote and set, predicted mean vote and wet bulb globe temperature are not suitable for athletes in the field environment.

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