Heat Acclimatization Guidelines Research Articles

Barriers and Facilitators Faced by Athletic Trainers Implementing National Athletic Trainers' Association Inter-Association Task Force Preseason Heat-Acclimatization Guidelines in US High School Football Players.

The aim of the National Athletic Trainers' Association Inter-Association Task Force (NATA-IATF) preseason heat-acclimatization guidelines was to acclimatize high school athletes to the environment during the first 2 weeks of the preseason and reduce the risk of exertional heat illness. To identify barriers and facilitators that high school athletic trainers (ATs) encountered when implementing the NATA-IATF guidelines. Qualitative study. Individual phone interviews with all participants. Thirty-three ATs (16 men, 17 women; age = 36.0 ± 12.0 years, athletic training experience = 12.9 ± 10.5 years) representing 19 states (4 with state mandates) were interviewed before data saturation was achieved. Participants were purposefully sampled from a larger investigation based on stratification of US Census region and preidentified high school compliance with the NATA-IATF guidelines. A cross-sectional, semistructured phone interview (6 steps) was conducted with each participant and then transcribed verbatim. A 7-person research team (5 coders, 2 auditors) coded the data into themes and categories, focusing on consensus of data placement to reduce bias and ensure accuracy. Facilitators and barriers that influenced successful guideline implementation were (1) perceived stakeholder access, (2) perceived stakeholder role, (3) capability and capacity, (4) school culture, (5) logistical support, (6) resources, (7) physical environment, and (8) consistency of the guidelines. Overall, participants discussed facilitators and barriers within each category based on their experiences and circumstances. Athletic trainers faced numerous concerns regarding compliance with the NATA-IATF preseason heat-acclimatization guidelines. Multiple levels of influence should be targeted to improve implementation. These include intrapersonal factors by giving ATs the education and self-efficacy to support advocacy for implementation, interpersonal components by establishing strong collaborative networks for change, community and environmental factors by optimizing school culture and community resources for implementation, and policy aspects by establishing consistent guidelines across all bodies.

Exertional Heat-Stroke Preparedness in High School Football by Region and State Mandate Presence

Exertional heat stroke (EHS) is a leading cause of sudden death in high school football players. Preparedness strategies can mitigate EHS incidence and severity. To examine EHS preparedness among high school football programs and its association with regional and state preseason heat-acclimatization mandates. Cross-sectional study. Preseason high school football programs, 2017. A total of 910 athletic trainers (ATs) working with high school football (12.7% completion rate). We acquired data on high school football programs' EHS preparedness strategies in the 2017 preseason via an online questionnaire, looking at (1) whether schools' state high school athletic associations mandated preseason heat-acclimatization guidelines and (2) heat safety region based on warm-season wet-bulb globe temperature, ranging from the milder region 1 to the hotter region 3. Six EHS-preparedness strategies were assessed: EHS recognition and treatment education; policy for initiating emergency medical services response; emergency response plan enactment; immersion tub filled with ice water before practice; wet-bulb globe temperature monitoring; and hydration access. Multivariable binomial regression models estimated the prevalence of reporting all 6 strategies. Overall, 27.5% of ATs described their schools as using all 6 EHS-preparedness strategies. The highest prevalence was in region 3 schools with state mandates (52.9%). The multivariable model demonstrated an interaction in which the combination of higher heat safety region and presence of a state mandate was associated with a higher prevalence of reporting all 6 strategies (P = .05). Controlling for AT and high school characteristics, the use of all 6 strategies was higher in region 3 schools with state mandates compared with region 1 schools without state mandates (52.9% versus 17.8%; prevalence ratio = 2.68; 95% confidence interval = 1.81, 3.95). Our findings suggest a greater use of EHS-preparedness strategies in environmentally warmer regions with state-level mandates for preseason heat acclimatization. Future researchers should identify factors influencing EHS preparedness, particularly in regions 1 and 2 and in states without mandates.

Compliance With the National Athletic Trainers' Association Inter-Association Task Force Preseason Heat-Acclimatization Guidelines in High School Football.

In 2009, the National Athletic Trainers' Association Inter-Association Task Force (NATA-IATF) released preseason heat-acclimatization guidelines for gradually acclimatizing high school (HS) athletes to the environment during the first 2 weeks of the preseason and reducing the risk of exertional heat illness. However, researchers who studied the 2011 preseason found a low level of overall compliance. To assess compliance with the NATA-IATF guidelines during the 2017 preseason and compare the findings with 2011 preseason data and between states mandating and not mandating the guidelines. Cross-sectional study. Preseason HS football, 2017. A total of 1023 athletic trainers working with HS football (14.2% response rate). Using a survey, we acquired information from athletic trainers on their HS football programs, including location and compliance with 17 NATA-IATF guidelines during the 2017 football preseason. The outcome measures were full compliance with all 17 NATA-IATF guidelines and compliance with ≥10 NATA-IATF guidelines. Prevalence ratios (PRs) with 95% confidence intervals (CIs) compared findings between (1) the 2017 and 2011 preseasons and (2) states whose HS athletic associations imposed a full or partial or no mandate to follow the NATA-IATF guidelines. Overall, 3.9% reported full compliance with NATA-IATF guidelines; 73.9% complied with ≥10 guidelines. The proportion reporting full compliance was higher in 2017 than in 2011 but not statistically different (3.9% versus 2.5%; PR = 1.54; 95% CI = 0.96, 2.46). However, the proportion reporting compliance with ≥10 guidelines was higher in 2017 (73.9% versus 57.9%; PR = 1.28; 95% CI = 1.20, 1.36). The proportion of respondents reporting their HSs were fully compliant was highest among the with-mandate group (9.4%), followed by the partial-mandate group (4.6%) and the without-mandate group (0.6%). Group differences retained significance when we examined compliance with ≥10 guidelines. Although full compliance with NATA-IATF guidelines remained low, many HS football programs complied with ≥10 guidelines.

State Regulations and Region Are Associated With High School Football Preseason Heat Acclimatization Guidelines Compliance

State Regulations and Region Are Associated With High School Football Preseason Heat Acclimatization Guidelines Compliance

The Association between Mandated Preseason Heat Acclimatization Guidelines and Exertional Heat Illness during Preseason High School American Football Practices.

Background:The risk of heat-related illness and death may continue to increase in many locations as a consequence of climate change, but information on the effectiveness of policies to protect populations from the adverse effects of excessive heat is limited. In 2009, the National Athletic Trainers’ Association Inter-Association Task Force (NATA-IATF) released guidelines to reduce exertional heat illness (EHI) among U.S. high school athletes participating in preseason sports activities, including preseason practice sessions for American football. A subset of state high school athletic associations have implemented state-mandated guidelines consistent with the 2009 NATA-IATF recommendations, but their effectiveness for reducing preseason EHI is unknown.Objectives:This study examines the association between the enactment of state high school athletic association–mandated NATA-IATF guidelines and the rate of EHI among high school students during preseason American football practice sessions.Methods:We performed a quasi-experimental interrupted time-series study of EHI during high school American football practices in the 2005/2006–2016/2017 school years. We estimated state-level EHI rates using High School Reporting Information Online injury and athlete-exposure data, and used generalized estimating equations Poisson regression models to estimate incidence rate ratios (IRRs) and 95% confidence intervals (CIs) comparing state-years with and without mandated NATA-IATF guidelines. State-level covariates included state-year–specific average August temperatures, yearly deviations from each state’s August average temperature across the study period, and school year.Results:Data were available for 455 state-years from 48 states, including 32 state-years (7.0%) from 8 states when mandated guidelines consistent with the NATA-IATF recommendations were implemented. During an estimated 2,697,089 athlete-exposures, 190 EHIs were reported. Estimated preseason EHI rates were lower during state-years with versus without mandated guidelines (adjusted , 95% CI: 0.23, 0.87).Conclusions:Our findings suggest that high school athletes would benefit from enactment of the 2009 NATA-IATF guidelines. Similar analyses of the effectiveness of other public health policies to reduce adverse health effects from ambient heat are warranted. https://doi.org/10.1289/EHP4163

Pre-deployment Heat Acclimatization Guidelines for Disaster Responders

Minimal preparation time is a feature of responding to sudden onset disasters. While equipment and supplies are prepared for deployment at short notice, less is known of the physical preparation of medical responders. With many disaster-prone areas classified as tropical regions, there is potential for responders to endure a combination of high ambient temperatures and relative humidity during deployment. Heat acclimatization, defined as the physiological and perceptual adaptations to frequent elevations of core body temperature (Tc), is a key strategy to improve tolerance of hot conditions by medical responders. Pre-deployment heat acclimatization guidelines were developed based upon the duration of physical training and the subjective rate of perceived exertion (session RPE). An objective of individual training sessions was the perception of body temperature as warm to hot. The guidelines were implemented for Team Bravo (2nd rotation) of the Australian Medical Assistance Team (AusMAT) deployed to Tacloban, Philippines following Typhoon Haiyan in November 2013. The guidelines were distributed electronically five to seven days prior to deployment and were followed by a consultation. A group training session in hot conditions was undertaken prior to departure. The AusMAT responders to utilize the guidelines were based in cool or temperate climates that required extra layers of clothing, training during warmer parts of the days, or warm indoor conditions to achieve session objectives. Responders reported the guidelines were simple to use, applicable to their varied training regimens, and had improved their confidence to work in the heat despite not completing the entire 14 day period. The pre-deployment heat acclimatization guidelines provided AusMAT responders the ability to quantify their physical training and promoted physiological adaptations to maximize health, safety, and performance during deployment. While maintaining year-round heat acclimatization is considered essential for medical responders, these guidelines may facilitate beneficial adaptations once notified of deployment.

Heat Stroke in Physical Activity and Sports (Original version in English)

Exertional heat stroke (EHS) is one of the leading causes of sudden death in sport and physical activity. In American Football alone, there have been 46-documented EHS fatalities in the United States between 1995 and 2010. In 2003, National Collegiate Athletics Association mandated pre-season heat acclimatization guidelines, which successfully decreased the number of heat stroke fatalities in collegiate American football. However, despite the advancement in modern medical care and increased awareness in heat safety, lack of appropriate on-site medical care is still contributing to EHS seen especially at the youth level. It is well established in scientific literature that fatalities as a result of EHS are largely preventable with proper education on the knowledge of recognition, treatment, and prevention of EHS. This document provides a review of the current best medical practices and evidence on the epidemiology, pathophysiology, risk factors, recognition, treatment, prevention, and return to play recommendations for EHS, specifically as they relate to sport and physical activity.

Heat-related illness in sports and exercise.

Exertional heat-related illness (EHRI) is comprised of several states that afflict physically active persons when exercising during conditions of high environmental heat stress. Certain forms of EHRI may become life threatening if not treated. Exertional heat stroke (EHS), characterized by a core body temperature of >40° C and mental status changes, is the most severe form of EHRI. EHS must be treated immediately with rapid body cooling to reduce morbidity and mortality. Many EHRI cases are preventable by following heat acclimatization guidelines, modifying sports and exercise sessions during conditions of high environmental heat stress, maintaining adequate hydration, avoiding exertion in the heat when ill, and by educating sports medicine personnel, coaches, parents, and athletes on the early recognition and prevention of EHRI. Heat exhaustion, exercise-associated collapse, exercise-associated muscle cramps, exercise-associated hyponatremia, and exertional rhabdomyolysis are also described.

Implementing Exertional Heat Illness Prevention Strategies in US High School Football

Approximately 6500 high school football athletes are treated annually for exertional heat illness (EHI). In 2009, the National Athletic Trainers Association (NATA)-led Inter-Association Task Force (NATA-IATF) released preseason heat acclimatization guidelines to help athletes become accustomed to environmental factors contributing to EHI. This study examines compliance with NATA-IATF guidelines and related EHI prevention strategies. The study used a cross-sectional survey completed by 1142 certified athletic trainers (AT), which captured compliance with 17 NATA-IATF guidelines and EHI prevention strategies in high school football during the 2011 preseason. On average, AT reported football programs complying with 10.4 NATA-IATF guidelines (SD = 3.2); 29 AT (2.5%) reported compliance with all 17. Guidelines with the lowest compliance were as follows: "Single-practice days consisted of practice no more than three hours in length" (39.7%); and "During days 3-5 of acclimatization, only helmets and shoulder pads should be worn" (39.0%). An average of 7.6 EHI prevention strategies (SD = 2.5) were used. Common EHI prevention strategies were as follows: having ice bags/cooler available (98.5%) and having a policy with written instructions for initiating emergency medical service response (87.8%). Programs in states with mandated guidelines had higher levels of compliance with guidelines and greater prevalence of EHI prevention strategies. A low proportion of surveyed high school football programs fully complied with all 17 NATA-IATF guidelines. However, many EHI prevention strategies were voluntarily implemented. State-level mandated EHI prevention guidelines may increase compliance with recognized best practices recommendations. Ongoing longitudinal monitoring of compliance is also recommended.

Exertional Heat Stroke Management Strategies in United States High School Football

Background: The 5-year period of 2005-2009 saw more exertional heat stroke–related deaths in organized sports than any other 5-year period in the past 35 years. The risk of exertional heat stroke appears highest in football, particularly during the preseason. Purpose: To estimate the incidence of exertional heat stroke events and assess the utilization of exertional heat stroke management strategies during the 2011 preseason in United States high school football programs. Study Design: Cross-sectional study; Level of evidence, 3. Methods: A self-administered online questionnaire addressing the incidence of exertional heat stroke events and utilization of exertional heat stroke management strategies (eg, removing athlete’s football equipment, calling Emergency Medical Services [EMS]) was completed in May to June 2012 by 1142 (18.0%) athletic trainers providing care to high school football athletes during the 2011 preseason. Results: Among all respondents, 20.3% reported treating at least 1 exertional heat stroke event. An average of 0.50 ± 1.37 preseason exertional heat stroke events were treated per program. Athletic trainers responding to exertional heat stroke reported using an average of 6.6 ± 1.8 management strategies. The most common management strategies were low-level therapeutic interventions such as removing the athlete’s football equipment (98.2%) and clothing (77.8%) and moving the athlete to a shaded area (91.6%). Few athletic trainers reported active management strategies such as calling EMS (29.3%) or using a rectal thermometer to check core body temperature (0.9%). Athletic trainers in states with mandated preseason heat acclimatization guidelines reported a higher utilization of management strategies such as cooling the athlete through air conditioning (90.1% vs 65.0%, respectively; P < .001), immersion in ice water (63.0% vs 45.4%, respectively; P = .01), or fans (54.3% vs 42.0%, respectively; P = .06) and monitoring the athlete’s temperature (60.5% vs 46.2%, respectively; P = .04). Conclusion: Preseason exertional heat stroke events, which are likely to be fatal if untreated, were reported by one fifth of all athletic trainers in high school football programs. The standard of care is (and should be) to treat proactively; therefore, treatment is not a perfect proxy for incidence. Nevertheless, there is an urgent need for improved education and awareness of exertional heat stroke in high school football. Areas of improvement include the greatly increased use of rectal thermometers and immersion in ice water.

Heat illness among high school athletes — United States, 2005–2009

Introduction Heat illness is a leading cause of death and disability among U.S. high school athletes. Methods To examine the incidence and characteristics of heat illness among high school athletes, CDC analyzed data from the National High School Sports-Related Injury Surveillance Study for the period 2005–2009. Results During 2005–2009, the 100 schools sampled reported a total of 118 heat illnesses among high school athletes resulting in ≥ 1 day of time lost from athletic activity, a rate of 1.6 per 100,000 athlete-exposures, and an average of 29.5 time-loss heat illnesses per school year. The average corresponds to a weighted average annual estimate of 9,237 illnesses nationwide. The highest rate of time-loss heat illness was among football players, 4.5 per 100,000 athlete-exposures, a rate 10 times higher than the average rate (0.4) for the eight other sports. Time-loss heat illnesses occurred most frequently during August (66.3%) and while practicing or playing football (70.7%). No deaths were reported. Conclusions Consistent with guidelines from the National Athletic Trainers’ Association, to reduce the risk for heat illness, high school athletic programs should implement heat-acclimatization guidelines (e.g., set limits on summer practice duration and intensity). All athletes, coaches, athletic trainers, and parents/guardians should be aware of the risk factors for heat illness, follow recommended strategies, and be prepared to respond quickly to symptoms of illness. Coaches also should continue to stress to their athletes the importance of maintaining proper hydration before, during, and after sports activities. Impact of industry By implementing preventive recommendations and quickly recognizing and responding to heat illness, coaches, athletic trainers, and the sporting community can prevent future deaths.

Preseason Heat-Acclimatization Guidelines for Secondary School Athletics

Inter-Association Task Force for Preseason Secondary School Athletics Participants: Lawrence E. Armstrong, PhD, FACSM ; Lindsay B. Baker, PhD`; Michael F. Bergeron, PhD, FACSM‰; Virginia M. Buchanan, JD ; Michael J. Carroll, MEd, LAT, ATCI; Michelle A. Cleary, PhD, LAT, ATCI; Edward R. Eichner, MD, FACSM ; Michael S. Ferrara, PhD, ATC, FNATAI; Tony D. Fitzpatrick, MA, LAT, ATCI; Jay R. Hoffman, PhD, FACSM, FNSCA; Robert W. Kenefick, PhD, FACSM#; David A. Klossner, PhD, ATCI; J. Chad Knight, MSHA, MESS, ATC, OTCI; Stephanie A. Lennon, MS, NBCT, LAT, ATCI; Rebecca M. Lopez, MS, ATCI; Matthew J. Matava, MD** ; Francis G. O’Connor, MD, FACSM ; Bart C. Peterson, MSS, ATCI; Stephen G. Rice, MD, PhD, FACSM, FAAP``; Brian K. Robinson, MS, LAT, ATCI; Robert J. Shriner, MS, LAT, ATCI; Michael S. West, MS, ATCI; Susan W. Yeargin, PhD, ATCI