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

Climate Change and Children's Health: Building a Healthy Future for Every Child

Observed changes in temperature, precipitation patterns, sea level, and extreme weather are destabilizing major determinants of human health. Children are at higher risk of climate-related health burdens than adults because of their unique behavior patterns; developing organ systems and physiology; greater exposure to air, food, and water contaminants per unit of body weight; and dependence on caregivers. Climate change harms children through numerous pathways, including air pollution, heat exposure, floods and hurricanes, food insecurity and nutrition, changing epidemiology of infections, and mental health harms. As the planet continues to warm, climate change's impacts will worsen, threatening to define the health and welfare of children at every stage of their lives. Children who already bear higher burden of disease because of living in low-wealth households and communities, lack of access to high quality education, and experiencing racism and other forms of unjust discrimination bear greater risk of suffering from climate change hazards. Climate change solutions, advanced through collaborative work of pediatricians, health systems, communities, corporations, and governments lead to immediate gains in child health and equity and build a foundation for generations of children to thrive. This technical report reviews the nature of climate change and its associated child health effects and supports the recommendations in the accompanying policy statement on climate change and children's health.

Catastrophic Sports Injuries: Causation and Prevention

➤ Catastrophic injuries in U.S. high school and college athletes are rare but devastating injuries.➤ Catastrophic sports injuries are classified as either traumatic, caused by direct contact during sports participation, or nontraumatic, associated with exertion while participating in a sport.➤ Football is associated with the greatest number of traumatic and nontraumatic catastrophic injuries for male athletes, whereas cheerleading has the highest number of traumatic catastrophic injuries and basketball has the highest number of nontraumatic catastrophic injuries for female athletes.➤ The incidence of traumatic catastrophic injuries for all sports has declined over the past 40 years, due to effective rule changes, especially in football, pole-vaulting, cheerleading, ice hockey, and rugby. Further research is necessary to reduce the incidence of structural brain injury in contact sports such as football.➤ The incidence of nontraumatic catastrophic injuries has increased over the last 40 years and requires additional research and preventive measures. Avoiding overexertion during training, confirming sickle cell trait status in high school athletes during the preparticipation physical examination, and developing cost-effective screening tools for cardiac abnormalities are critical next steps.

Variations of wet-bulb globe temperature across high school athletics in South Carolina

The purpose was to describe wet bulb globe temperature (WBGT) throughout a high school fall athletic season (August to November) after a state-wide mandate requiring schools to use a WBGT-guided activity modification table with categories (AMTC). A cross-sectional research design utilized 30 South Carolina high schools. The independent variables were region (upstate, midlands, and coastal), sport (football, tennis, cross-country), month, start times (7-10 am, 10 am-3 pm, 3-6 pm, and 6-9 pm), and event type (practice, competition). Dependent variables were event frequency, average WBGT, and AMTC. Practice WBGT was 78.7 ± 8.2 °F (range: 34.7 to 99.0 °F). A significant difference for WBGT across month (F₆, 904.7 = 385.07, P < 0.001) existed, with early September hotter than all other months (84.8 °F ± 3.8, P < 0.001). Every month had practices in each AMTC, until early November. Most events (64.6%, n = 1986) did not change AMTC; however, 9.1% (n = 281) changed to a hotter category. The 10 am-3 pm start time was significantly hotter than all other time frames (83.0 °F ± 7.2, P < 0.05). Tennis experienced hotter practices (79.9 °F ± 6.9) than football (78.4 °F ± 8.5; P < 0.001) and cross country (78.2 °F ± 8.8, P < 0.001). Schools in the Midlands experienced hotter practices (80.1 °F ± 7.8) than upstate (P < 0.001) and coastal schools (P = 0.005). Competition WBGT was significantly cooler than practices (72.3 ± 10.5 °F, t = 12.04, P < 0.001) and differed across sports (F₂, 20.78 = 18.39, P < .001). Both cross-country (P = 0.003) and tennis (P < 0.001) were hotter than football. Schools should continuously monitor WBGT throughout practices and until November to optimize AMTC use. Risk mitigation strategies are needed for sports other than football to decrease the risk of exertional heat illnesses.

Effect of high ambient temperature on physiological responses during incremental exercise in Thoroughbred horses

Several reports have suggested that the risk of exertional heat illness (EHI) in Thoroughbred racehorses increases in high ambient temperatures. Heat dissipation in horses during exercise becomes less efficient when the body temperature and ambient temperature are close. Therefore, we hypothesised that exercise at 40 °C may increase body temperature, oxygen consumption, and cardiac output during incremental exercise tests compared to 20 and 30 °C. Six trained Thoroughbred horses were studied in a randomised, crossover design at three ambient temperatures with a 6-day washout period. Using a 3% inclined treadmill, horses performed incremental exercise tests at 1.7, 3.5, 6, 8, and 10 m/s for 90 s at ambient temperatures of 20, 30, and 40 °C. The effects of ambient temperature at 10 m/s on physiological variables were analysed using mixed models (P<0.05). Pulmonary arterial temperature and rectal temperature at 40 °C were higher than those at 20 °C (P<0.001) and 30 °C (P<0.001). Similarly, oxygen consumption (vs 20 °C, P=0.009; vs 30 °C, P=0.006) and cardiac output (vs 20 °C, P=0.001; vs 30 °C, P=0.001) at 40 °C were higher than those at 20 and 30 °C. Arterial O2 partial pressure, O2 saturation, and pH at 40 °C were lower than those at 20 and 30 °C. Arterial CO2 partial pressure at 40 °C was higher than that at 20 and 30 °C. No differences were observed in arterial-mixed venous O2 concentration difference (P=0.391) and plasma lactate concentration (P=0.134) at different ambient temperatures. These results indicate that exercise at 40 °C causes excessive high body temperature, decreased running economy, and increased cardiac output compared to exercise at 20 and 30 °C. We strongly suggest that trainers and veterinarians should anticipate the occurrence of increased thermal stresses when ambient temperature is extremely high even in dry conditions and prepare to mitigate the risk of EHI from the perspective of equine welfare.

Increasing Health Risks During Outdoor Sports Due To Climate Change in Texas: Projections Versus Attitudes

Extreme heat is a recognized threat to human health. This study examines projected future trends of multiple measures of extreme heat across Texas throughout the next century, and evaluates the expected climate changes alongside Texas athletic staff (coach and athletic trainer) attitudes toward heat and climate change. Numerical climate simulations from the recently published Community Earth System Model version 2 and the Climate Model Intercomparison Project were used to predict changes in summer temperatures, heat indices, and wet bulb temperatures across Texas and also within specific metropolitan areas. A survey examining attitudes toward the effects of climate change on athletic programs and student athlete health was also distributed to high-school and university athletic staff. Heat indices are projected to increase beyond what is considered healthy/safe limits for outdoor sports activity by the mid-to-late 21st century. Survey results reveal a general understanding and acceptance of climate change and a need for adjustments in accordance with more dangerous heat-related events. However, a portion of athletic staff still do not acknowledge the changing climate and its implications for student athlete health and their athletic programs. Enhancing climate change and health communication across the state may initiate important changes to athletic programs (e.g., timing, duration, intensity, and location of practices), which should be made in accordance with increasingly dangerous temperatures and weather conditions. This work employs a novel interdisciplinary approach to evaluate future heat projections alongside attitudes from athletic communities toward climate change.

Factors Affecting Incidence Rate of Exertional Heat Illnesses: Analysis of 6 Years of High School Football Practices in North Central Florida

Background

Although experts have advocated for regionally specific heat safety guidelines for decades, guidelines have not been universally adopted.

Purpose

To describe the rate and risk factors associated with exertional heat illness (EHI).

Study Design

Descriptive epidemiology study.

Methods

For a 3-month period (August-October) over 6 years (2013-2018), athletic trainers at 13 high schools in North Central Florida recorded varsity football practice time and length, wet-bulb globe temperature (WBGT), and incidences of EHI, including heat stroke, heat exhaustion, and heat syncope.

Results

Athletes sustained 54 total EHIs during 163,254 athlete-exposures (AEs) for the 3-month data collection periods over 6 years (incidence rate [IR], 3.31 /10,000 AEs). Heat exhaustion accounted for 59.3% (32/54), heat syncope 38.9% (21/54), and heat stroke 1.9% (1/54) of all EHIs recorded. Of the EHIs, 94.4% (51/54) were experienced within the first 19 practices. The first 19 practices had an IR of 7.48 of 10,000 AEs, and the remaining 44 practices had an IR of 0.32 of 10,000 AEs, demonstrating that the risk of EHI for practices 1 to 19 was 23.7 times that of the remaining practices. When comparing morning to afternoon practices, 35.2% (19/54) EHI incidents occurred during morning practices. The risk of EHI during practices with WBGT >82°F (27.8°C) was 3.5 times that of practices with WBGT <82°F.

Conclusion

In the current study, the risk of EHI was greatest in the first 19 practices of the season and during practices with WBGT >82°F. As modifiable risk factors for EHI, increased vigilance and empowerment to adhere to acclimatization guidelines can mitigate EHI risk. Health care providers must continue to advocate for implementation of regulations and the authority to make decisions to ensure patient safety.

Roundtable on Preseason Heat Safety in Secondary School Athletics: Environmental Monitoring During Activities in the Heat

OBJECTIVE

To develop best-practice recommendations using thermal indices to determine work-to-rest ratios and facilitate further implementation of environmental monitoring for heat safety in secondary school athletics in the United States.

DATA SOURCES

A narrative review of the current literature in environmental monitoring for heat safety during athletics was conducted by content experts. A list of action-oriented recommendations was established from the narrative review and further refined using the Delphi method.

CONCLUSIONS

Assessment of wet bulb globe temperature at the site of activity throughout the duration of the event is recommended to assist clinicians and administrators in making appropriate decisions regarding the duration and frequency of activity and rest periods. Activity modification guidelines should be predetermined and approved by stakeholders and should outline specific actions to be followed, such as the work-to-rest ratio, frequency and timing of hydration breaks, and adjustment of total exercise duration, equipment, and clothing. Furthermore, integration of exertional heat illness injury data with environmental condition characteristics is critical for the development of evidence-based heat safety guidelines for secondary school athletics. Athletic trainers play an essential role in conducting prospective injury data collection, recording onsite wet bulb globe temperature levels, and implementing recommendations to protect the health and safety of athletes.

The Effects of On-Field Heat Index and Altitude on Concussion Assessments and Recovery Among NCAA Athletes

BACKGROUND

Recent literature has indicated altitude may be a protective factor for concussion but it is unknown whether altitude or heat index affects recovery.

OBJECTIVE

To examine whether on-field heat index and altitude at the time of injury alter acute (< 48 h) concussion assessments, days-to-asymptomatic, and days-to-return-to-play in collegiate athletes following concussion.

METHODS

Collegiate athletes (n = 187; age = 19.7 ± 1.4 years; male = 70.6%) underwent baseline assessments across 30 universities and experienced a concussion in this retrospective cohort study. Altitude (m) and heat index (°C) at the time and location of injury were determined using valid online database tools. Acute concussion assessments included the Sport Concussion Assessment Tool (SCAT) symptom inventory, Balance Error Scoring System (BESS), and the Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT). We used multiple linear regression models to determine whether heat index and altitude predicted each acute assessment outcome, days-to-asymptomatic, and days-to-return-to-play.

RESULTS

Collegiate athletes were concussed at a 181.1 m (range - 0.6 to 2201.9 m) median altitude and 17.8 °C (range - 6.1 to 35.6 °C) median heat index. Altitude did not predict (p ≥ 0.265) any outcomes. Every one-degree increase in heat index reduced days-to-asymptomatic (p = 0.047; R² = 0.06) and days-to-return-to-play (p = 0.006; R² = 0.09) by 0.05 and 0.14 days, respectively. Heat index and altitude did not explain significant variance in SCAT, BESS, and ImPACT composite scores (p's = 0.20-0.922).

CONCLUSION

Our findings suggest that on-field altitude and heat index at the time of injury do not contribute to clinically meaningful changes on acute assessments or concussion recovery. On-field altitude and heat index do not appear to significantly alter assessment outcomes or clinical recovery, suggesting that environmental factors at altitudes below < 2500 m are negligible outcomes for researchers and clinicians to consider post-concussion.

Illness and infection in elite full-contact football-code sports: A systematic review

OBJECTIVES

Full-contact football-code team sports offer a unique environment for illness risk. During training and match-play, players are exposed to high-intensity collisions which may result in skin-on-skin abrasions and transfer of bodily fluids. Understanding the incidence of all illnesses and infections and what impact they cause to time-loss from training and competition is important to improve athlete care within these sports. This review aimed to systematically report, quantify and compare the type, incidence, prevalence and count of illnesses across full-contact football-code team sports.

DESIGN/METHODS

A systematic search of Cochrane Library, MEDLINE, SPORTDiscus, PsycINFO and CINAHL electronic databases was performed from inception to October 2019; keywords relating to illness, athletes and epidemiology were used. Studies were excluded if they did not quantify illness or infection, involve elite athletes, investigate full-contact football-code sports or were review articles.

RESULTS

Twenty-eight studies met the eligibility criteria. Five different football-codes were reported: American football (n=10), Australian rules football (n=3), rugby league (n=2), rugby sevens (n=3) and rugby union (n=9). One multi-sport study included both American football and rugby union. Full-contact football-code athletes are most commonly affected by respiratory system illnesses. There is a distinct lack of consensus of illness monitoring methodology.

CONCLUSIONS

Full-contact football-code team sport athletes are most commonly affected by respiratory system illnesses. Due to various monitoring methodologies, illness incidence could only be compared between studies that used matching incidence exposure measures. High-quality illness surveillance data collection is an essential component to undertake effective and targeted illness prevention in athletes.

Exertional Heat Illness Preparedness Strategies: Environmental Monitoring Policies in United States High Schools

Background and objectives: Environmental monitoring allows for an analysis of the ambient conditions affecting a physically active person’s ability to thermoregulate and can be used to assess exertional heat illness risk. Using public health models such as the precaution adoption process model (PAPM) can help identify individual’s readiness to act to adopt environmental monitoring policies for the safety of high school athletes. The purpose of this study was to investigate the adoption of policies and procedures used for monitoring and modifying activity in the heat in United States (US) high schools. Materials and Methods: Using a cross-sectional design, we distributed an online questionnaire to athletic trainers (ATs) working in high schools in the US. The questionnaire was developed based on best practice standards related to environmental monitoring and modification of activity in the heat as outlined in the 2015 National Athletic Trainers’ Association Position Statement: Exertional Heat Illness. The PAPM was used to frame questions as it allows for the identification of ATs’ readiness to act. PAPM includes eight stages: unaware of the need for the policy, unaware if the school has this policy, unengaged, undecided, decided not to act, decided to act, acting, and maintaining. Invitations were sent via email and social media and resulted in 529 complete responses. Data were aggregated and presented as proportions. Results: Overall, 161 (161/529, 30.4%) ATs report they do not have a written policy and procedure for the prevention and management of exertional heat stroke. The policy component with the highest adoption was modifying the use of protective equipment (acting = 8.2%, maintaining = 77.5%). In addition, 28% of ATs report adoption of all seven components for a comprehensive environmental monitoring policy. Conclusions: These findings indicate a lack of adoption of environmental monitoring policies in US high schools. Secondarily, the PAPM, facilitators and barriers data highlight areas to focus future efforts to enhance adoption.

Regional Requirements Influence Adoption of Exertional Heat Illness Preparedness Strategies in United States High Schools

Background and objectives: Exertional heat stroke (EHS) continues to be a prevalent health issue affecting all athletes, including our pediatric populations. The purpose of this study was to evaluate the effect of a state policy requirement for EHS prevention and treatment on local high school policy adoption in the United States (US). Materials and Methods: Athletic trainers (ATs) from high schools across the US participated in an online survey (n = 365). This survey inquired about their compliance with nine components of an EHS policy which was then compared to their state requirements for the policies. Evaluation of the number of components adopted between states with a requirement versus states without a requirement was conducted with a Wilcoxon Sign Rank test. Finally, an ordinal logistic regression with proportional odds ratios (OR) with 95% confidence intervals (CI) were run to determine the effect of a state requirement and regional differences on the number of components adopted. Results: ATs working in states with a requirement reported adoption of more components in their heat modification policy compared to states that did not require schools to develop a heat modification policy (with requirement mean = 5.34 ± 3.68, median = 7.0; without requirement mean = 4.23 ± 3.59, median = 5.0; Z = -14.88, p < 0.001). ATs working in region 3 (e.g., hotter regions) reported adopting more components than those in region 1 (e.g., cooler regions) (OR = 2.25, 95% CI: 1.215-4.201, p = 0.010). Conclusions: Our results demonstrate a positive association between state policy requirements and subsequently increased local policy adoption for EHS policies. Additionally, the results demonstrate that regional differences exist, calling for the need for reducing disparities across the US. These findings may imply that policy adoption is a multifactorial process; furthermore, additional regional specific investigations must be conducted to determine the true determinants of high school policy adoption rates for EHS policies.

Test and Evaluation of Heart Rate Derived Core Temperature Algorithms for Use in NCAA Division I Football Athletes

The purpose of this study was to assess the validity of utilizing heart rate to derive an estimate of core body temperature in American Football athletes. This was evaluated by combining commercially available Zephyr Bioharness devices, which includes an embedded estimated core temperature (ECT) algorithm, and an ingestible radio frequency core temperature pill during the highest heat injury risk timepoint of the season, summer training camp. Results showed a concordance of 0.643 and 78% of all data points fell within +/-1.0 °F. When the athletes were split into Upper (>/=6.0%) and Lower (<6.0%) body composition groups, there was a statistical improvement in accuracy with the Upper Body Fat% reaching 0.834 concordance and 93% of all values falling within +/-1.0 °F of the Gold Standard. Results suggest that heart rate derived core temperature assessments are a viable tool for heat stress monitoring in American football, but more work is required to improve on accuracy based on body composition.

Heat Policy Revision for Georgia High School Football Practices Based on Data-Driven Research

CONTEXT

Interscholastic heat policies for football have not been evidence based. Therefore, their effectiveness in mitigating exertional heat illness has not been assessed.

OBJECTIVE

To discuss the development of the Georgia High School Association heat policy and assess the effectiveness of revised guidelines.

DESIGN

Descriptive epidemiology study.

SETTING

Georgia high schools.

PATIENTS OR OTHER PARTICIPANTS

Interscholastic football players in grades 9 through 12.

MAIN OUTCOME MEASURE(S)

Heat syncope and heat exhaustion (HS/HE) illness rates (IRs) were calculated per 1000 athlete-exposures (AEs), and relative risk (RR) was calculated as a ratio of postpolicy (POST) IR divided by prepolicy (PRE) IR.

RESULTS

A total of 214 HS/HE cases (172 PRE, 42 POST) and 341 348 AEs (178 230 PRE, 163 118 POST) were identified. During the first 5 days of the PRE period, approximately 50% of HS/HE illnesses occurred; HS/HE IRs doubled when practice sessions increased from 2 to 2.5 hours and tripled for practices ≥3 hours. The HS/HE IRs in the PRE period increased from 0.44/1000 AEs for wet-bulb globe temperatures (WBGTs) of <82°F (<27.8°C) to >2.0/1000 AEs for WBGTs from 87°F (30.6°C) to 89.9°F (32.2°C). The RRs comparing PRE and POST policy periods were 0.29 for WBGTs of <82.0°F (<27.80°C), 0.65 for WBGTs from 82.0°F (27.8°C) to 86.9°F (30.5°C), and 0.23 for WBGTs from 87.0°F (30.6°C) to 89.9°F (32.2°C). No HS/HE illnesses occurred in the POST period for WBGTs at >90°F (>32.3°C).

CONCLUSIONS

Results from the PRE period guided the Georgia High School Association to revise its heat and humidity policy to include a mandated 5-day acclimatization period when no practices may exceed 2 hours and the use of WBGT-based activity-modification categories. The new policy reduced HS/HE IRs by 35% to 100%, depending on the WBGT category. Our results may be generalizable to other states with hot and humid climates similar to that of Georgia.

Regional differences in exertional heat illness rates among Georgia USA high school football players

Many high school associations in recent years are developing policies to improve player safety regarding exertional heat illnesses (EHIs). A question is whether states with diverse climates need multiple sets of guidelines with different activity modification thresholds. We examine this question in the state of Georgia, which has a diverse climate. Our study leverages a multi-year dataset of exertional heat illnesses (EHIs) among high school football players to test the hypothesis that EHI rates under similar wet bulb globe temperatures (WBGTs) will be greater among athletes in the cooler, northern region versus warmer, southern region of the state. The focus of this study is on a 3-year period (2012-2014) when uniform heat safety polices, including acclimatization and activity modification guidelines, were implemented across the state. Results show that athletes in the northern region acclimatize to cooler conditions. Almost 68% of practices have WBGTs < 27.8 °C (82 °F) compared to the southern region where athletes receive many times the exposures to hotter WBGTs in the 27.8-30.5 °C and 30.6-32.2 °C categories. In the post-acclimatization period, we observed statistically significantly (p < .05) greater EHI rates among athletes in the northern region of the state, even when controlling for meteorological conditions. Our findings suggest that differential acclimatization between football players in the northern and southern regions of the state is impacting EHI rates and that regional heat safety guidelines may be needed in Georgia and other states with similarly diverse climates.

Risk factors for exertional heat illness in Thoroughbred racehorses in flat races in Japan (2005-2016)

BACKGROUND

Exertional heat illness (EHI) is recognised in horses, but few reports have investigated its risk factors.

OBJECTIVES

To identify risk factors for EHI in racehorses participating in flat races in Japan.

STUDY DESIGN

Descriptive epidemiology and retrospective unmatched case-control study.

METHODS

Between 2005 and 2016, veterinary records of horses diagnosed with EHI after flat races were reviewed retrospectively and data of the months from April to September were used for a case-control study. For each case, three control horses were randomly selected from starts between April and September. Race records of horses and estimated wet-bulb globe temperature (WBGT) indexes at the local meteorological observatory closest to the racecourse were investigated. To identify risk factors for EHI, univariable and multivariable logistic regression analysis was used.

RESULTS

Of 194 cases during the study period, 188 cases occurred between April and September. The highest incidence risk was in July (1.1 cases per 1000 starts, 95% confidence interval 0.84-1.45). In the final multivariable model, WBGT index, sex, race distance, age and bodyweight were associated with EHI. When WBGT index exceeded 28°C, the risk of EHI was considerably higher than <20°C (OR 28.5, 14.2-62.4, P<0.001). Compared with uncastrated males, geldings (OR 4.9, 1.8-13.3, p = 0.002) and females (OR 2.4, 1.5-3.7, P<0.001) were at high risk of EHI (P<0.01). Furthermore, races of >1600 m (OR 1.8, 1.2-2.8, P = 0.002), 4-year-old (OR 3.5, 1.6-7.9, P = 0.002) and ≥5-year-old (OR 3.9, 1.8-9.2, P = 0.001) horses and horses with low bodyweight (OR per 20 kg, 0.8, 0.7-1.0, P = 0.02) were associated with increased risk of EHI.

MAIN LIMITATIONS

The median straight-line distance between the racecourse and the local meteorological observatory was 14.2 km (range, 1.1-28.3 km). There was a lack of objective criteria of EHI due to the retrospective nature of the study.

CONCLUSIONS

We identified specific risk factors for EHI in racehorses. These results may be useful to the equine industry for reducing EHI occurrence in racehorses.

Preventing Catastrophic Injury and Death in Collegiate Athletes: Interassociation Recommendations Endorsed by 13 Medical and Sports Medicine Organisations

The Second Safety in College Football Summit resulted in interassociation consensus recommendations for three paramount safety issues in collegiate athletics: (1) independent medical care for collegiate athletes; (2) diagnosis and management of sport-related concussion; and (3) year-round football practice contact for collegiate athletes. This document, the fourth arising from the 2016 event, addresses the prevention of catastrophic injury, including traumatic and non-traumatic death, in collegiate athletes. The final recommendations in this document are the result of presentations and discussions on key items that occurred at the summit. After those presentations and discussions, endorsing organisation representatives agreed on 18 foundational statements that became the basis for this consensus paper that has been subsequently reviewed by relevant stakeholders and endorsing organisations. This is the final endorsed document for preventing catastrophic injury and death in collegiate athletes. This document is divided into the following components. (1) Background-this section provides an overview of catastrophic injury and death in collegiate athletes. (2) Interassociation recommendations: preventing catastrophic injury and death in collegiate athletes-this section provides the final recommendations of the medical organisations for preventing catastrophic injuries in collegiate athletes. (3) Interassociation recommendations: checklist-this section provides a checklist for each member school. The checklist statements stem from foundational statements voted on by representatives of medical organisations during the summit, and they serve as the primary vehicle for each member school to implement the prevention recommendations. (4) References-this section provides the relevant references for this document. (5) Appendices-this section lists the foundational statements, agenda, summit attendees and medical organisations that endorsed this document.

Preventing catastrophic injury and death in collegiate athletes: interassociation recommendations endorsed by 13 medical and sports medicine organisations

The following organisations endorsed this document: American Association of Neurological Surgeons, American Medical Society for Sports Medicine, American Orthopaedic Society for Sports Medicine, American Osteopathic Academy of Sports Medicine, College Athletic Trainers' Society, Collegiate Strength and Conditioning Coaches Association, Congress of Neurological Surgeons, Korey Stringer Institute, National Athletic Trainers' Association, National Strength and Conditioning Association, National Operating Committee for Standards on Athletic Equipment, Sports Neuropsychology Society. The following organisation has affirmed the value of this document: American Academy of Neurology. The Second Safety in College Football Summit resulted in interassociation consensus recommendations for three paramount safety issues in collegiate athletics: (1) independent medical care for collegiate athletes; (2) diagnosis and management of sport-related concussion; and (3) year-round football practice contact for collegiate athletes. This document, the fourth arising from the 2016 event, addresses the prevention of catastrophic injury, including traumatic and non-traumatic death, in collegiate athletes. The final recommendations in this document are the result of presentations and discussions on key items that occurred at the summit. After those presentations and discussions, endorsing organisation representatives agreed on 18 foundational statements that became the basis for this consensus paper that has been subsequently reviewed by relevant stakeholders and endorsing organisations. This is the final endorsed document for preventing catastrophic injury and death in collegiate athletes. This document is divided into the following components. (1) Background-this section provides an overview of catastrophic injury and death in collegiate athletes. (2) Interassociation recommendations: preventing catastrophic injury and death in collegiate athletes-this section provides the final recommendations of the medical organisations for preventing catastrophic injuries in collegiate athletes. (3) Interassociation recommendations: checklist-this section provides a checklist for each member school. The checklist statements stem from foundational statements voted on by representatives of medical organisations during the summit, and they serve as the primary vehicle for each member school to implement the prevention recommendations. (4) References-this section provides the relevant references for this document. (5) Appendices-this section lists the foundational statements, agenda, summit attendees and medical organisations that endorsed this document.

Exertional Heat Stroke within Secondary School Athletics

Exertional heat stroke (EHS) remains one of the leading causes of sudden death in sport despite clear evidence showing 100% survivability with the proper standards of care in place and utilized. Of particular concern are student athletes competing at the secondary school level, where the extent of appropriate health care services remains suboptimal compared with organized athletics at the collegiate level and higher. While rapid recognition and rapid treatment of EHS ensures survival, the adoption and implementation of these lifesaving steps within secondary school athletics warrant further discussion within the sports medicine community. Establishing proper policies regarding the prevention and care of EHS coupled with utilizing an interdisciplinary care approach is essential for 1) minimizing risk and 2) guaranteeing optimal outcomes for the patient.

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 [Formula: see text], 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.

The Socioecological Framework: A Multifaceted Approach to Preventing Sport-Related Deaths in High School Sports

The socioecological framework is a multilevel conceptualization of health that includes intrapersonal, interpersonal, organizational, environmental, and public policy factors. The socioecological framework emphasizes multiple levels of influence and supports the idea that behaviors both affect and are affected by various contexts. At present, the sports medicine community's understanding and application of the socioecological framework are limited. In this article, we use the socioecological framework to describe potential avenues for interventions to reduce sport-related deaths among adolescent participants.

Activity modification in heat: critical assessment of guidelines across athletic, occupational, and military settings in the USA

Exertional heat illness (EHI) risk is a serious concern among athletes, laborers, and warfighters. US Governing organizations have established various activity modification guidelines (AMGs) and other risk mitigation plans to help ensure the health and safety of their workers. The extent of metabolic heat production and heat gain that ensue from their work are the core reasons for EHI in the aforementioned population. Therefore, the major focus of AMGs in all settings is to modulate the work intensity and duration with additional modification in adjustable extrinsic risk factors (e.g., clothing, equipment) and intrinsic risk factors (e.g., heat acclimatization, fitness, hydration status). Future studies should continue to integrate more physiological (e.g., valid body fluid balance, internal body temperature) and biometeorological factors (e.g., cumulative heat stress) to the existing heat risk assessment models to reduce the assumptions and limitations in them. Future interagency collaboration to advance heat mitigation plans among physically active population is desired to maximize the existing resources and data to facilitate advancement in AMGs for environmental heat.

Epidemiology of Exertional Heat Illnesses in National Collegiate Athletic Association Athletes During the 2009-2010 Through 2014-2015 Academic Years

CONTEXT

Exertional heat illnesses (EHIs) among football athletes have been widely researched, but data examining all collegiate sports are limited.

OBJECTIVE

To describe the epidemiology of EHI in 25 National Collegiate Athletic Association (NCAA) sports.

DESIGN

Descriptive epidemiology study.

SETTING

The NCAA Injury Surveillance Program during the 2009-2010 through 2014-2015 academic years.

PATIENTS OR OTHER PARTICIPANTS

A voluntary sample of 166 NCAA institutions over 2048 team-seasons.

MAIN OUTCOME MEASURE(S)

Athletic trainers reported EHIs to the NCAA Injury Surveillance Program. Only EHIs sustained during a sanctioned practice or competition were included. The EHI rate, specific diagnoses, and number of emergency transports were measured.

RESULTS

Overall, 232 EHI events were reported (0.47/10 000 athlete-exposures [AEs]; 95% confidence interval [CI] = 0.41, 0.53). Football comprised 75% of all EHI events and had the largest rate (1.55/10 000 AEs; 95% CI = 1.32, 1.78). The overall EHI rate was higher in preseason practices (1.16/10 000 AEs) than all other time periods (regular and postseason practices and all competitions; 0.23/10 000 AEs, injury rate ratio [IRR] = 4.96; 95% CI = 3.79, 6.50). This result was retained when examining the individual sports of football (3.65/10 000 versus 0.63/10 000 AEs, IRR = 5.82; 95% CI = 4.18, 8.10), men's soccer (1.11/10 000 versus 0.07/10 000 AEs, IRR = 16.819; 95% CI = 1.89, 138.55), and women's soccer (1.10/10 000 versus 0.05/10 000 AEs, IRR = 22.52; 95% CI = 2.77, 183.05). The EHI rates were highest in states with elevated annual temperatures (1.05/10 000 AEs). Heat cramps (39%), heat exhaustion (27%), and dehydration (29%) were the most common types of EHI. Nineteen athletes with EHI (8%) required emergency transport.

CONCLUSIONS

Football players continue to experience the most EHIs; however, EHIs can potentially occur in all NCAA sports. Continued emphasis on preseason EHI policies and institution-specific environmental guidelines is needed to address EHI rates.

Assessment of the Australian Bureau of Meteorology wet bulb globe temperature model using weather station data

Exertional heat illnesses affect thousands of athletes each year and are a leading cause of death in sports. The wet bulb globe temperature (WBGT) is widely used as a heat stress metric in athletics for adjusting activities. The WBGT can be measured on-site with portable sensors, but instrument cost may provide a barrier for usage. Modeling WBGT from weather station data, then, presents an affordable option. Our study compares two WBGT models of varying levels of sophistication: the Australian Bureau of Meteorology (ABM) model which uses only temperature and humidity as inputs and a physically based model by Liljegren that incorporates temperature, humidity, wind speed, and solar radiation in determining WBGT outputs. The setting for the study is 19 University of Georgia Weather Network stations selected from across the state of Georgia, USA, over a 6-year period (2008-2014) during late summer and early fall months. Results show that the ABM model's performance relative to the Liljegren model varies based on time of day and weather conditions. WBGTs from the ABM model are most similar to those from the Liljegren model during midday when the assumption of moderately high sun most frequently occurs. We observed increasingly large positive biases with the ABM model both earlier and later in the day during periods with lower solar radiation. Even during midday, large (≥ 3 °C) underestimates may occur during low wind conditions and overestimates during periods with high cloud cover. Such differences can lead to inaccurate activity modification and pose dangers for athletes either by underestimating heat-related hazards or by imposing an opportunity cost if practice activities are limited by overestimating the heat hazard.

Assessment of Evidence-Based Health and Safety Policies on Sudden Death and Concussion Management in Secondary School Athletics: A Benchmark Study

CONTEXT: 

Implementation of best-practice health and safety policies has been shown to be effective at reducing the risk of sudden death in sport; however, little is known about the extent to which these policies are required within secondary school athletics.

OBJECTIVE: 

To examine best-practice health and safety policies pertaining to the leading causes of sudden death and to concussion management in sport mandated at the state level for secondary school athletics.

DESIGN: 

Descriptive observational study.

SETTING: 

State high school athletic associations (SHSAAs), state departments of education, and enacted legislation.

PATIENTS OR OTHER PARTICIPANTS: 

United States (including the District of Columbia) SHSAAs.

MAIN OUTCOME MEASURE(S): 

A review of SHSAA health and safety policies for the 2016-2017 academic year, state department of education policies, and enacted legislation was undertaken to assess the polices related to the leading causes of sudden death and concussion management in sport. Current best-practice recommendations used to assess health and safety policies were specific to emergency action plans, automated external defibrillators, heat acclimatization, environmental monitoring and modification, and concussion management. The total number of best-practice recommendations required for each SHSAA's member schools for the aforementioned areas was quantified and presented as total number and percentage of recommendations required.

RESULTS: 

Four of 51 SHSAA member schools were required to follow best practices for emergency action plans, 7 of 51 for access to automated external defibrillators, 8 of 51 for heat acclimatization, and 3 of 51 for management of concussion.

CONCLUSIONS: 

At the time of this study, SHSAA member schools were not required to follow all best-practice recommendations for preventing the leading causes of sudden death and for concussion management in sport. Continued advocacy for the development and implementation of best practices at the state level to be required of all secondary schools is needed to appropriately serve the health and well-being of our young student-athletes.

Fatal Exertional Heat Stroke and American Football Players: The Need for Regional Heat-Safety Guidelines

CONTEXT

  Weather-based activity modification in athletics is an important way to minimize heat illnesses. However, many commonly used heat-safety guidelines include a uniform set of heat-stress thresholds that do not account for geographic differences in acclimatization.

OBJECTIVE

  To determine if heat-related fatalities among American football players occurred on days with unusually stressful weather conditions based on the local climate and to assess the need for regional heat-safety guidelines.

DESIGN

  Cross-sectional study.

SETTING

  Data from incidents of fatal exertional heat stroke (EHS) in American football players were obtained from the National Center for Catastrophic Sport Injury Research and the Korey Stringer Institute.

PATIENTS OR OTHER PARTICIPANTS

  Sixty-one American football players at all levels of competition with fatal EHSs from 1980 to 2014.

MAIN OUTCOME MEASURE(S)

  We used the wet bulb globe temperature (WBGT) and a z-score WBGT standardized to local climate conditions from 1991 to 2010 to assess the absolute and relative magnitudes of heat stress, respectively.

RESULTS

  We observed a poleward decrease in exposure WBGTs during fatal EHSs. In milder climates, 80% of cases occurred at above-average WBGTs, and 50% occurred at WBGTs greater than 1 standard deviation from the long-term mean; however, in hotter climates, half of the cases occurred at near average or below average WBGTs.

CONCLUSIONS

  The combination of lower exposure WBGTs and frequent extreme climatic values in milder climates during fatal EHSs indicates the need for regional activity-modification guidelines with lower, climatically appropriate weather-based thresholds. Established activity-modification guidelines, such as those from the American College of Sports Medicine, work well in the hotter climates, such as the southern United States, where hot and humid weather conditions are common.

An Evaluation of Portable Wet Bulb Globe Temperature Monitor Accuracy

CONTEXT

  Wet bulb globe temperature (WBGT) is the gold standard for assessing environmental heat stress during physical activity. Many manufacturers of commercially available instruments fail to report WBGT accuracy.

OBJECTIVE

  To determine the accuracy of several commercially available WBGT monitors compared with a standardized reference device.

DESIGN

  Observational study.

SETTING

  Field test.

PATIENTS OR OTHER PARTICIPANTS

  Six commercially available WBGT devices.

MAIN OUTCOME MEASURE(S)

  Data were recorded for 3 sessions (1 in the morning and 2 in the afternoon) at 2-minute intervals for at least 2 hours. Mean absolute error (MAE), root mean square error (RMSE), mean bias error (MBE), and the Pearson correlation coefficient ( r) were calculated to determine instrument performance compared with the reference unit.

RESULTS

  The QUESTemp° 34 (MAE = 0.24°C, RMSE = 0.44°C, MBE = -0.64%) and Extech HT30 Heat Stress Wet Bulb Globe Temperature Meter (Extech; MAE = 0.61°C, RMSE = 0.79°C, MBE = 0.44%) demonstrated the least error in relation to the reference standard, whereas the General WBGT8778 Heat Index Checker (General; MAE = 1.18°C, RMSE = 1.34°C, MBE = 4.25%) performed the poorest. The QUESTemp° 34 and Kestrel 4400 Heat Stress Tracker units provided conservative measurements that slightly overestimated the WBGT provided by the reference unit. Finally, instruments using the psychrometric wet bulb temperature (General, REED Heat Index WBGT Meter, and WBGT-103 Heat Stroke Checker) tended to underestimate the WBGT, and the resulting values more frequently fell into WBGT-based activity categories with fewer restrictions as defined by the American College of Sports Medicine.

CONCLUSIONS

  The QUESTemp° 34, followed by the Extech, had the smallest error compared with the reference unit. Moreover, the QUESTemp° 34, Extech, and Kestrel units appeared to offer conservative yet accurate assessments of the WBGT, potentially minimizing the risk of allowing physical activity to continue in stressful heat environments. Instruments using the psychrometric wet bulb temperature tended to underestimate WBGT under low wind-speed conditions. Accurate WBGT interpretations are important to enable clinicians to guide activities in hot and humid weather conditions.