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Original Research

National Collegiate Athletic Association Strength and Conditioning Coaches' Knowledge and Practices Regarding Prevention and Recognition of Exertional Heat Stroke

Valdes, Anna S.; Hoffman, Jay R.; Clark, Margaret H.; Stout, Jeffrey R.

Author Information
Journal of Strength and Conditioning Research: November 2014 - Volume 28 - Issue 11 - p 3013-3023
doi: 10.1519/JSC.0000000000000365
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Abstract

Introduction

Exertional heat stroke (EHS) deaths are preventable and the strength and conditioning coach (SCC), the professional responsible for implementing and supervising strength and conditioning programs, may be held responsible if EHS deaths occur as a result of inappropriate exercise prescription or monitoring programs (3). Mueller and Colgate (14) in their survey of football injuries reported 132 EHS deaths from 1960 to 2011; a rate of 2.5 deaths per year. In the past 10 years, these investigators have reported that the rate of EHS deaths seems to be increasing. Between the years 2002 and 2012, 32 deaths during football practices at the high school, collegiate, or professional levels have been attributed to EHS (14). Most of these deaths occurred during conditioning sessions during preseason (the first 4 days) practice and not during competitive games (8). The fatal incidents reported at National Collegiate Athletic Association (NCAA) institutions have often occurred while athletes were training under the supervision of the team's strength and conditioning coach (8). Further troubling was the fact that all of these fatalities occurred when wet bulb globe temperature (WBGT), the “gold standard” for measuring ambient temperature, was well above what is considered safe (8). It is likely that if American College of Sports Medicine (ACSM) and National Athletic Trainers Association (NATA) guidelines for exercise safety in the heat were followed by the SCC, many, if not all, of the EHS casualties may have been prevented. Therefore, establishing competencies, training, and assessments to ensure that SCCs are competent regarding prevention and recognition of EHS may be an important first step in reducing the incidence of EHS in NCAA football and other sports.

Exertional heat stroke is a life-threatening condition caused by increasing body temperature (hyperthermia), central nervous system dysfunction, and multiple organ failure (4). There is a substantial body of scientific literature examining the etiology and incidence of EHS. These have led to a number of position stands and review articles providing recommendations for the prevention, recognition, and treatment of EHS (4,6,7,17). Despite this knowledge, deaths continue to occur. Football players seem to be particularly susceptible to EHS for 2 major reasons: (a) much of the preseason training occurs during the warmer parts of the year and (b) football requires extra equipment (helmets and pads), which prevent effective cooling, increases metabolic heat production, and increases the risk for hyperthermia (8).

The common message emanating from the various position stands and guidelines of various professional sports medicine organizations is that through education the ability to prevent EHS, to recognize symptoms of EHS, and to treat EHS are enhanced (4,16,17). For the SCC, it can be argued that their professional responsibilities are primarily concerned with the first 2 areas: prevention and recognition. Therefore, the SCC needs to understand assessment of intrinsic and extrinsic factors, which permit recognition of early signs and symptoms of EHS and early treatment. The intrinsic factors (athlete's health history) include: underlying illness, low physical fitness, dehydration, sleep deprivation, and overweight/obese athletes. Extrinsic factors (external/environmental) include: improper acclimatization to the environment, training practices that do not match athletes physical fitness level, and not using WBGT as a guide to determine whether practices have to be modified, delayed, or cancelled (1,2,4,5,8). However, there is no published requirement to date that suggests minimal knowledge requirements for SCC on environmental issues.

The SCC is an integral part of support staff or coaching staff of all NCAA Division I, most Division II, and many Division III programs (11). The 2 primary certifications for SCCs are the National Strength and Conditioning Association (NSCA)-Certified Strength and Conditioning Specialist (CSCS) and the Collegiate Strength & Conditioning Coaches Association (CSCCA) Strength and Conditioning Coach Certification (SCCC). Both the NSCA and the CSCCA have defined a scope of practice and established guidelines for the profession, limit certification to those who have earned a bachelors degree from an accredited institution, and require candidates to pass a standardized examination. Although each of these organizations has different requirements of knowledge, skills, and abilities (KSA) to become a certified SCC, neither of these certifications includes EHS as part of their KSA requirements. Some differences in the certification process between the 2 certifications do exist. The NSCA CSCS certification examination is accredited by the National Commission for Certifying Agencies (NCCA), whereas the CSCCA SCCC is not. The NCCA is an independent agency that reviews and accredits certification providers. The NCCA was created to ensure that health/fitness certifications examination and the process of testing administration meets minimum standards of quality, validity, and reliability. Regardless of the rigor of either of these 2 certifications, no legal requirement exists (e.g., licensure) for an SCC to earn either of these 2 certifications. This is because the SCC profession is not a regulated profession. Therefore, who may or may not be competent to work as an SCC in NCAA sports is solely decided by each independent NCAA institution. Each individual school determines which credentials, KSA the SCC should possess.

Despite the extensive literature pertaining to EHS prevention and recognition, it remains unclear whether the SCC possesses the necessary knowledge regarding the prevention and recognition of EHS. Previous studies have examined the knowledge of athletic trainers on issues relating to EHS (5,12). Those studies indicated that certified athletic trainers were not consistent regarding their ability to recognize and treat EHS. Considering the number of fatal injuries that have been related to conditioning practices in the past 10 years, it would be prudent for SCC to demonstrate skills and knowledge in preventing, recognizing, and treating heat illnesses in their athletes. Thus, the purpose of this study was to investigate the knowledge of NCAA SCCs regarding EHS and to determine whether there is a difference in their level of knowledge based on certification type: CSCS vs. SSSC. Consequently, because this is the first study to do so, it will establish a baseline level of knowledge that can be used to assess if progress has been made in increasing the competency of SCCs and other professionals in this area. The secondary purpose was to gain additional information about SCC's attitudes and current practices in dealing with prevention and recognition of EHS.

Methods

Experimental Approach to the Problem

This research study used a causal comparative research design to compare 2 certification groups on 5 measures of EHS knowledge. The purpose was to assess SCCs' current level of knowledge, attitudes, and current practices regarding prevention and recognition of EHS and to determine whether certification type yielded any differences in this knowledge. An online questionnaire containing Likert items, “yes/no” questions and open-ended questions was made available to the population of NCAA SCCs with published e-mails, and they were provided with ample opportunity to participate in the study.

Since no validated instrument exists to measure SCC's EHS knowledge, one was developed for this study. An instrument previously used and validated for athletic trainers was adapted for SCCs, pilot tested, and validated (12). A panel of EHS experts, and educators (n = 9) created relevant 30 Likert-type items, using a 7-point scale (1 = strongly disagree, 7 = strongly agree), which were intended to measure EHS knowledge and related subfactors for SCCs. The panel was chosen based on their research experience with EHS and the SCC profession as determined by their degree, publication record, university affiliation, and experience. The process yielded 4 subfactors in areas of EHS knowledge: extrinsic risk factors (ERF), intrinsic risk factors (IRF), recognition of EHS (R), and general training safety knowledge (TSK). To determine the internal consistency of the instrument, a pilot study was conducted on a group of 210 undergraduate and graduate students majoring in sport and exercise science from a large southern university. Cronbach's alpha was calculated for the composite score and for each of the 4 subfactors. Cronbach's alpha for all 30 items measuring EHS knowledge was 0.74. After removing items with low internal consistency, Cronbach's alpha for each of the 4 subfactors (shown in Table 1) suggested that the measures were reliable. The final instrument consisted of 24 items. The IRF subfactor contained 7 items, ERF contained 8 items, R contained 6 items, and TSK contained 3 items. Six additional closed-ended “yes” or “no” questions were also included. An open-ended response section was used to ask questions about current practices in strength and conditioning regarding conditioning in the heat. Ten demographics questions were included at the end of the survey. SurveyMonkey was used to create the instrument and to e-mail the instrument in a survey style format. It also maintained anonymity of the participants.

Table 1
Table 1:
Exertional Heat Stroke questionnaire content.

Subjects

A total of 1305 SCCs, representing NCAA Division I, II, and III, were surveyed. The survey was conducted between June and August 2012. The study received approval from the university's institutional review board and appropriate informed consent was gained. The participants were guaranteed anonymity. Participants were categorized into 4 certification groups: (a) only earned the CSCS certification (CSCS), (b) only earned the SCCC certification (SCCC), (c) earned both certifications (CSCS/SCCC), and (d) held neither of the 2 certifications (NC).

Procedures

The entire population of SCCs with e-mails listed on the school's athletic/sports site (n = 1305) were included in the study. The list of all NCAA SCCs was developed by conducting a web search of all NCAA institutions and their athletic Web sites. The contact e-mail sent to all SCCs on the created list provided instructions and a link to the surveys Web site on SurveyMonkey. Although nonrespondents were sent a follow-up e-mail encouraging them to participate, all coaches were assured anonymity and the right not to participate in any part of the study.

Statistical Analyses

Likert-type items were recoded as being correct if the response marked was ≥5 or incorrect if the response ≤4. For those statements where the correct answer was “disagree” or “strongly disagree,” the statements were reverse coded. Mean and SD values were calculated for the number of correct answers on the Total, IRF, ERF, R, and TSK scales. To compare the effect of certification on total score and the score of each subfactor, a 1-way analysis of variance was used. In the event of a significant F ratio, least significant differences post hoc tests were used for pairwise comparisons. A criterion alpha level of p ≤ 0.05 was used to determine statistical significance. All data are reported as mean ± SD.

The qualitative data collected from the open-ended questions were examined for general themes. The qualitative comments and themes were used to triangulate and supplement the quantitative results to better understand the gaps and problems in the knowledge of prevention and recognition of EHS and to further explore SCCs' attitudes, beliefs, and practices.

Results

Demographics

Of the 1305 SCCs who were asked to participate, 354 responded to the survey. This resulted in a 27.1% response rate that met the desired goal of >25%. Of the 354 that responded, 319 had completed the necessary information to conduct analysis of the research questions relating to total score, IRF, ERF, R, and TSK knowledge scales. Demographic characteristics of the coaches completing the survey are shown in Table 2. No significant interactions were found between groups regarding education, experience, and/or NCAA division of employment.

Table 2
Table 2:
Demographics.*

Strength and Conditioning Coaches' Knowledge of Prevention and Recognition of Exertional Heat Stroke

Table 3 provides the performance results of SCC knowledge of EHS on all questions combined (total score) and each of the specific constructs (IRF, ERF, R, and TSK). When examining content knowledge on the entire survey (i.e., total score), only 7 (2.2%) coaches scored ≥90%, whereas 151 (47%) earned a score ≤59%. Analysis of the results for each the constructs on the scale reveals that for IRF, 56 (17.6%) of the coaches scored ≥90%, whereas 102 (32%) scored ≤59%. Only 1 participant scored ≥90% on ERF and 112 (35%) scored ≤59%. For R, 8 (2.5%) participants scored ≥90% and 152 (54%) scored ≤59%. Training safety knowledge results indicate that 21 (6.6%) participants scored ≥90% and 178 (55.8%) scored ≤59%.

Table 3
Table 3:
Exertional Heat Stroke Scale results percentage correct.*

Differences Between Certification Groups

Comparisons between certification groups on each subfactor of EHS knowledge are shown in Table 4. There was a significant difference in the total score between the certification groups (F(3,315) = 10.376, p ≤ 0.001). Those with NCs scored significantly lower on total score than those with other certifications (CSCS, p ≤ 0.001; SCCC, p = 0.039; CSCS/SCCC, p ≤ 0.001). Coaches holding both certifications (CSCS/SCCC) performed significantly better on total EHS knowledge than those with just SCCC (p = 0.047), whereas coaches holding only the CSCS certification scored 5 percentage points higher on the total score than SCCC. Although this difference was not statistically different (p = 0.085), it did trend toward a difference. Analysis of group differences on the individual subfactors revealed significant differences in IRF (F(3,315) = 10.455, p ≤ 0.001); ERF (F(3,315) = 5.803, p = 0.001); R (F(3,315) = 3.012, p = 0.031); and TSK (F(3,315) = 7.089, p ≤ 0.001). Post hoc analysis indicated that the CSCS (p ≤ 0.001), SCCC (p = 0.009), and CSCS/SCCC (p ≤ 0.001) groups scored significantly higher on IRF than NC, but were not statistically different from each other. Coaches holding the CSCS (p ≤ 0.001) and the combined CSCS/SCCC (p ≤ 0.001) certifications scored significantly higher than NC on ERF, whereas a trend toward a difference (p = 0.078) was seen between coaches with the SCCC certification and NC. Those coaches with CSCS certification had higher R scores that those with NC (p = 0.034) and SCCC (p = 0.051), whereas coaches holding both the CSCS and SCCC certifications scored significantly better in this area than coaches only holding SCCC certification (p = 0.036). The NC group scored significantly lower than CSCS (p ≤ 0.001), CSCS/SCCC (p ≤ 0.001), and SCCC (p = 0.011) in TSK; but the latter 3 groups did not differ from each other.

Table 4
Table 4:
Certification group means andSD.*

Individual Item Correct Responses and Frequencies

To further understand content areas where factual knowledge about EHS may be lacking, low or inadequate, the individual Likert-type items were analyzed based on percentage of SCCs who correctly agreed or disagreed with each of the statements regardless of certification group. Table 5 describes the percentage of SCCs who correctly identified the “true” or “false” statements from the IRF scale. Only 55.7% of SCCs correctly agreed that highly self-motivated athletes may be at a higher risk for EHS, 62.7% correctly agreed that body composition should be used to assess risk, and only 61.4% correctly disagreed that athletes who are sick or febrile can continue playing or training provided they are given frequent rest periods.

Table 5
Table 5:
Percentage of SCCs who correctly answered IRF statements.*

Review of the responses for the ERF construct can be observed in Table 6. Results indicated that 51.4% of SCCs correctly identified that EHS can occur in cool environments; with 14% correctly disagreeing with the statement that EHS can only happen in hot environment. Regarding the use of WBGT to assess environmental temperature and risk for heat illness, 65.8% agreed that WBGT should be used.

Table 6
Table 6:
Percentage of SCCs who correctly answered.*

Review of SCC responses regarding recognizing the signs and symptoms of EHS (Table 7) indicated several areas where knowledge level was low or inadequate. The most disconcerting finding was that only 13% of SCC correctly identified that individuals with EHS do not usually stop sweating. Only 50.2% of SCCs correctly identified that changes in athletic performance should trigger an assessment for EHS, whereas 53.5% agreed that changes in personality should trigger an assessment for EHS. Only 50.7% of SCC correctly identified that the onset of EHS is not random and unpredictable.

Table 7
Table 7:
Percentage of SCCs who correctly answered R statements.*

Coaches were asked 3 questions on general TSK. Responses indicated that 40.7% of SCC agreed with the statement that “the strain of an exercise session can enhance mental toughness of an athlete.” Regarding coaches knowledge regarding muscle soreness and creatine kinase elevations, 78.3% of SCC correctly disagreed with the statement that severe muscle soreness is a desired outcome of hard training session, and 34.5% of the SCCs understood that creatine kinase would be elevated after training.

Acclimatization and Wet Bulb Globe Temperature

The second section of the questionnaire asked about practices regarding the use of WBGT and acclimatization. The SCCs were asked whether they use WBGT to assess environmental temperature. Of the 240 participants who answered the question, only 23% of SCCs indicated that they assess environmental temperature using WBGT as recommended by the NATA and ACSM. The reported barriers for the use of WBGT are shown in Table 8.

Table 8
Table 8:
Barriers to using WBGT.*

Respondents were asked whether an institution should follow a heat acclimatization period. Of the 242 coaches responding to this question, 88% indicated that an institution should follow an acclimatization period. The open-ended section allowed for an explanation of acclimatization methods used and the major themes are described in Table 9.

Table 9
Table 9:
Acclimatization themes.*

Return-to-Play Protocol

Review of the responses regarding return-to-play protocol after EHS revealed 3 major themes. The most common theme reported was that the medical staff (athletic trainers and team physicians) is responsible for making the decision on whether the athlete was ready to return-to-play. Other themes included assessment of body weight before return-to-play and being fully hydrated. A few also answered “not sure” indicating that they may not be familiar with what a return-to-play protocol may entail. Table 10 describes the most common responses.

Table 10
Table 10:
Return-to-play who makes the decision?

Modifications to Outdoor Workouts

The SCCs were also asked what changes, if any, they would make to outdoor workouts based on environmental temperature. The most interesting outcome was the lack of knowledge or utilization by the SCCs on WBGT to make decisions about modifying or canceling practice. The major themes are shown in Table 11. The most common response among the coaches was to decrease training volume, provide longer rest periods, and allow for more water breaks. Other responses also included monitoring the heat to make decisions, decrease duration of practice, increase the number of breaks, and change time of practice to cooler times of the day. Several SCCs reported that they would not make any changes to outdoor workouts based on the temperature.

Table 11
Table 11:
Changes to outdoor workouts based on WBGT.*

Discussion

The primary purpose of this study was to assess SCCs' current level of knowledge on EHS and to determine whether SCC certification type was an indicator that SCCs were knowledgeable in this area. The results of this study suggest that the SCCs' demonstrated level of knowledge on EHS is low (60% correct responses). Coaches who have earned the CSCS certification seemed to have a greater level of knowledge, as related to the total score and each individual construct, than SCCs without any certification. Coaches with the CSCS certification or with both CSCS and SCCC certifications seemed to score better on the total score than coaches who only held the SCCC certification.

Coaches' demonstrated knowledge on IRFs associated with EHS indicated that they were lacking in several areas. Coaches seemed to be unable to identify that highly motivated or overzealous athletes, athletes who are overweight (BMI ≥ 30) or with a high body fat percentage, and athletes with a current illness or fever were at an increased risk for EHS. However, coaches holding the CSCS certification, or both the CSCS/SCCC certifications, performed significantly higher in knowledge of IRF than those who did not have an SCC certification. Interestingly, coaches who held only SCCC certification did not score significantly higher than those who did not have any SCC certification.

Coaches' deficiencies in ERFs for EHS were also apparent. The major ERF concepts where knowledge seemed to be low included understanding that EHS can occur in hot or cool environments, uniforms with protective equipment should only be added after proper acclimatization has been completed, and WBGT should be the instrument used to assess ambient temperatures. SCCs seemed particularly unclear about the possibility that EHS can occur in cooler environments, or whether EHS can only occur in hot environment. Many SCCs answered that they were not familiar with the WBGT to assess ambient temperature, with only 23% of SCCs reported to be using it. More importantly, none of the SCCs completing the open-ended response questions about acclimatization and adjustment of outdoor workouts based on ambient temperature described using WBGT to make these decisions. Instead of WBGT, SCCs reported using the heat index though the Internet. This is a particularly troublesome finding because Grundstein et al. (8) found that the heat index was not a reliable source to determine “uncompensable” heat stress because it tended to underestimate the danger especially for athletes who were not fully acclimatized to the heat. They noted that most of the football-related EHS deaths occurred under conditions rated as extremely dangerous by WBGT but assigned lower risk levels according to the heat index. The major problem with using the heat index is that it fails to account for sun exposure (radiation), whereas WBGT accounts for it. Although ERF knowledge was low among SCCs and highlights an area where more education is needed, CSCS- and CSCS/SCCC-certified SCCs did score significantly greater than SCC who had neither certification. The results of the open-ended questions on acclimatization practices and the use of WBGT are consistent with the findings from the Likert-type items. Although 88% of SCCs reported following an acclimatization period for athletes, the methods reported were inconsistent between the SCCs, and many did not follow the published guidelines as set forth by ACSM, NATA, and NCAA (1,2,17). In particular, NCAA standards were cited by several SCCs as their source for developing an acclimatization protocol, yet they described a 5-day acclimatization period and not the 7–10 days as it is actually described and recommended by NCAA (NATA and ACSM describe up to 14 days) (1,2). These suggest that further education is needed in proper acclimatization and in the use of WBGT during in the training season. Although most SCCs reported practicing an acclimatization plan, their methods were varied and inconsistent.

Regarding the relationship between hydration and hyperthermia, the findings of this study were encouraging. The majority of SCCs (89%) disagreed with the practice of forced dehydration and were cognizant of the importance of proper hydration as a preventive measure for EHS. SCCs seem to understand that dehydration increases the risk for hyperthermia. This knowledge was particularly evident in the open-ended section where proper hydration was a predominant theme consistently reported by SCCs as important to training and performance and described as essential in dealing with training in the heat, return-to-play, and acclimatization.

The findings of this study also indicated that SCCs lack the necessary knowledge and skills to properly recognize signs and symptoms of EHS. In the area of recognition, 75% of the SCCs mistakenly believed that EHS victims would not sweat. This presents a significant problem because SCCs may continue to allow athletes to participate in conditioning sessions as long as they observe them sweating, potentially exacerbating heat illness or delaying an assessment for EHS. Casa et al. (3) identified this as a potential risk and a common problem, and being a misconception in the early detection of EHS. SCCs also exhibited a low level of understanding regarding the relationship between changes in personality and performance, and recognizing these changes as possible signs of impending EHS, with many erroneously believing that EHS is random and unpredictable. This finding is consistent with the work of Casa et al. (4) on EHS in competitive athletes, where they noted that this misconception exists in the field that “EHS is random and unpredictable.” Part of the responsibility of the SCC is recognizing signs and symptoms of EHS, which includes noting atypical behavior or performance in their athletes, cease exercise, and access medical care immediately. By knowing their athletes well enough to note any changes in personality or behavior, they can intervene early in the survival chain before the athlete collapses. Failure to do so may result in a catastrophic event. The skill and ability needed to recognize EHS should not fall outside the scope of practice for an SCC.

Unsafe training practices can increase the risk of EHS. Although many SCCs correctly identified that training intensity should not be used to enhance mental toughness, a high number of coaches (40.7%) still believed that it should be used for that purpose. This is a dangerous belief with no scientific evidence to support its use and with new evidence that mental toughness may not be “trainable” but genetic in nature (7). In a study, Horsburgh et al. (9) compared fraternal and identical twins to determine whether mental toughness was learned or was a genetic personality trait. They found that mental toughness correlated the highest among identical as opposed to fraternal twins, concluding that mental toughness was a genetic personality trait and not trained. Evidence of this “old school” attitude described in the literature as dangerous (10) was observed in several of the open-ended responses where SCCs noted that they would not make any changes to outdoor practices or would not allow football players to practice without helmets or pads regardless. The majority (78.3%) of SCCs seem to understand the concept that severe muscle soreness is not a desired outcome of hard training. Severe muscle soreness usually leads to rhabdomyolysis and is associated with an exercise intensity or volume that far exceeds the athletes' level of fitness (3,15). As previously discussed, if work/rest ratios and exercise intensity is unmatched with the athlete's fitness level, the risk for all medical emergencies increases. It does seem that most SCCs understand the relationship between increased muscle soreness and health risk.

Practical Applications

This study is the first to assess and determine the current level of knowledge that NCAA SCCs possess regarding EHS prevention and recognition. Specific content areas where knowledge was lacking were identified. Important findings of this study suggest that SCCs need to continue education and to increase their level of competency in preventing and recognizing EHS. Organizations such as the ACSM, CSCCA, NATA, NCAA, and NSCA should either continue efforts to disseminate information about EHS prevention, recognition, and treatment to SCCs. Additional consideration should be made on including environmental physiological as part of the Exercise Science curriculum in academic preparation programs for coaches. Consideration should also be made in requiring coaches to be assessed on EHS as part of the certification and/or recertification processes.

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    Keywords:

    certifications; football deaths; training practices; training safety

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