Exertion-related illness (ERI), despite aggressive efforts with both prevention and emergency action planning, continues to be a considerable threat to both athletes and warfighters (1,2). Principal events where prevention has focused include sudden cardiac arrest (SCA), exertional heat stroke (EHS), exercise collapse associated with sickle cell trait (ECAST), and exertional rhabdomyolysis (ER) (3,4). SCA is unique from the other listed etiologies in that affected individuals often carry an occult disease that is unmasked by exertion and, therefore, may offer the unique opportunity for detection prior to participation through athletic preparticipation examinations and advanced testing (5). In addition to SCA prevention through screening, where there is no clear consensus or standardization, strong evidence supports implementation of emergency action planning that includes early and effective automated external defibrillator utilization (6,7).
Epidemiologic reviews of case reports and case series consistently identify intrinsic and extrinsic risk factors where prevention could have optimally addressed and likely mitigated the risk factors (2,8–11). Common extrinsic risk factors for ERI — EHS, ECAST, and ER include environmental conditions (e.g., altitude, heat, and humidity), training workload, and medication and/or supplement utilization. Intrinsic factors include recent illness, prior exertion-related events, age, body mass index, baseline fitness, genetic predisposition, and others. Recently, the National Collegiate Athletic Association (NCAA) highlighted an additional key risk factor, published in an Inter-Association Task Force guidance: clear identification of predictable periods of athlete vulnerability and the need to modify the training workload accordingly (2). As previously discussed, despite efforts at prevention, these conditions remain significant problems and in some cases are increasing in frequency.
The NCAA Inter-Association Task Force Report additionally noted that many of these ERI occur in cohorts during distinct training sessions. Our 2018 publication in Military Medicine detailed a cohort cluster of ER, where we introduced the critical roles of both the leader and the follower, which had been largely heretofore underrecognized risk factors (9). In this commentary, we cite a recently developed leader-follower conceptual framework and explore how it might be used to help evaluate previously described ERI cohort events. We then conclude by describing how this leader-follower framework can assist the sports medicine community in further mitigation of ERI.
How might consideration of this leader-follower framework help prevent ERI? Would additional education and development of leaders and followers help prevent ERI? First, we distinguish among the terms: leadership, leaders, followership, and followers, and then we discuss how they can contribute to ERI prevention.
“Leadership” refers to social capital, interpersonal relationships, organizations, and cultures (12). Leadership is how a leader influences individuals and groups by enhancing behaviors (actions), cognitions (perceptions, thoughts, and beliefs), and motivations (why we act and think as we do) to achieve goals that benefit the individuals and groups (13–16). “Leaders” refer to human capital with intrapersonal knowledge, skills, abilities, attitudes, and motivations (12). Leaders are aspirational (setting vision and goals) and inspirational — they drive these processes and remove barriers for individuals and teams to achieve their united goal(s). “Followership” refers to actions (or inactions) of individuals not in leadership roles. “Followers” are members of a team or group who contribute (or not), align (or not), and adapt (or not) with the leader to achieve their common goal (17).
There are many different leader types (e.g., adaptive, authoritative, democratic, laissez-faire, servant, transactional, translational) and each type can be effective, depending on the leaders, followers, and situations (15,18). We believe that the most effective leaders adapt, learn, and change based on understanding of oneself, those who are led, and the context to achieve optimal performance and morale among followers as individuals and as teams. This type of leader uses a variety of leader styles to be most effective and is referred to as an “allostatic” leader (19). Several different follower types (e.g., isolate, bystander, participant, activist, die hard) also need to be distinguished (20); their effectiveness depends on the individual leader, followers, and situations (12). Leaders and followers who understand their own tendencies and can draw from the varied leader and follower styles (depending on context and goals) are most likely to optimize effective outcomes and perhaps minimize negative outcomes, including illnesses and injuries.
The Figure below presents a recently published conceptual framework, developed to guide the education, development, and assessment of leaders and followers in military health care (13,14). This framework also is relevant for educating and developing leaders and followers more broadly to include those involved in the prevention of ERI. The authors of this framework considered and drew from principles and approaches in the extant leadership literature as well as the Service academies (U.S. Air Force Academy, U.S. Coast Guard, U.S. Military Academy, and U.S. Naval Academy). The framework includes four “C” elements — character, competence, context, and communication — that operate across four levels of interaction — Personal (within each individual), Interpersonal (between dyads), Team (within and among small interdependent groups), and Organizational (PITO). Character refers to “who” the person is (including demographics, physical characteristics, personality, attitudes, and values). Competence refers to role-specific knowledge and skills (e.g., as a coach, as a particular type of athlete, as a warfighter) and transcendent knowledge and skills (e.g., critical thinking, decision making, problem solving, emotional intelligence). Context refers to physical (inside and outside), psychosocial, cultural, and situational (e.g., stress) variables. Communication refers to sending and receiving information, verbally and nonverbally (including word choice, tone and volume, body language). These C elements operate and interact across and within the four “PITO” levels.
Although the roles, responsibilities, and authorities of leaders and followers differ, sometimes leaders and followers each should “lead” (i.e., take initiative, inspire others, set vision) and other times, each should “follow” (i.e., listen carefully, respond to input and feedback). Understanding and developing leadership and followership can be another ingredient to help prevent devastating effects of ERI. With regard to the prevention and early detection of ERI, the leaders (including physicians, coaches, strength training staff, athletic trainers, team captains, dietitians) and followers (i.e., athletes and service members who undergo strenuous activities) all have responsibilities and opportunities to prevent illnesses and injuries. The leader-follower framework may help guide prevention of ERI by considering the elements of this approach. For example:
Character within this framework would include the physical and psychological differences of individuals that may contribute to the likelihood of ERI. These characteristics could include: sickle cell trait; body composition, physical fitness, personal drive; reactions to competition (e.g., the likelihood that individuals push themselves to extremes when competing), and personal motivation. Leaders and followers should be aware of these characteristics to monitor and self-monitor symptoms that might signal the onset of an ERI.
Competence includes the ability to perform a given task. Leaders and followers must be well-aware of their abilities, including their natural talents and preparedness at a particular time. Competence also includes the emotional and social intelligence to be aware of and detect the onset of a dangerous or life-threatening condition.
Context includes the immediate physical and mental conditions inside (e.g., hydration, nutrition, rest, confidence) and outside (e.g., temperature, humidity, precipitation) each individual; the immediate social environment (e.g., cooperative vs competitive); and cultural variables (e.g., responses to authority, demands, guilt, embarrassment, shame). Importantly, while motivation can be an intrinsic personal characteristic as previously described, the individual is contextually subject to extrinsic motivators (e.g., pending scholarship, contract, and fame). Awareness of these conditions and how they might affect individuals are relevant to preventing ERI.
Communication is key — what are the implicit and explicit verbal and nonverbal words and cues being transmitted? How are leaders and followers sending and receiving information? How is that information being “perceived”? Clear, accurate, and effective communication is critical most importantly during competition when the pressure is high. The leader and follower must continually be able to calmly and evenly send and receive information that conveys the possible onset of health risks. This information might appear in the way someone looks, their pattern of speech, their eyes and face, their body movement, and so on. Remaining focused when an issue is emerging is essential and requires cooperation among and across the entire team — leaders and followers.
Overall, leaders and followers must learn how to evaluate aspects of these four “C” elements within themselves (personal); when interacting with other individuals (Interpersonal); when interacting with or training groups (teams); and with regard to the overall group, institution, or culture (organizational). Appropriate evaluations and actions take determination, openness, and being able to move nimbly in time of urgent events.
Exertion-Related Illness Case Reports and Series
The sports medicine literature is robust with case reports and series detailing the clinical presentation and management of both athletes and warfighters afflicted with ERI (9,11,21–25). These reports help illuminate risk factors, both intrinsic and extrinsic, to assist in explaining why individuals, many of whom were able to tolerate comparable previous stressors, become casualties of ERI. Whereas EHS, ER, and ECAST are unique entities with distinct pathophysiologies, they share many common previously published risk factors (Table). Multiple variables, such as poor functional fitness, novel overexertion, lack of acclimatization, and concurrent illness, are commonly cited in these reports. At the same time, increasing evidence supports the critical roles of both the leader and follower in the development of an ERI.
The role of individual motivation, whether to either individually succeed or outperform a teammate or competitor, has recently drawn interest in both the military and civilian ERI literature. In a recent review of 182 EHS persons in the French military, excessive motivation was the intrinsic factor most frequently reported by the participants (8). The authors hypothesized that during physical exercise, the combination of increased circulating levels of β-endorphin and excessive motivation could increase the threshold stress and thereby explain the lack of awareness regarding prodromal signs. Whereas ER was traditionally a problem largely seen in military recruits, increasing numbers of case reports associated with extreme exercise (as well as new or novel workouts) are appearing in civilian fitness communities. Brogan et al. (26) reported on 46 cases of spin-induced rhabdomyolysis: 42 of these cases occurred after the first spin class (26). Patients who developed exertional rhabdomyolysis in many of the cases were described as “deconditioned.” The authors went on to call for safety guidelines for prevention, with beginners needing to know how to gradually increase the time and cadence on the indoor cycle. Additionally, ECAST events are well described in the literature with a distinctive clinical presentation, generally as a result of an intense individual effort (24,27). A review of the 31-year United States Sudden Death in Athletes Registry identified 23 deaths in association with SCT (28). In these cases, each athlete experienced a distinctive collapse, which usually occurred during conditioning drills early in the training season, often when athletes are competing for roles on a team.
Whereas individual case reports are insightful into ERI, cohort studies have been more illustrative of the role of both leaders (e.g., physicians, coaches, strength-training staff, athletic trainers) and followers (e.g., athletes, service members). Eichner (29) has published several reviews detailing the phenomenon of “team rhabdomyolysis.” In 2016, he added two additional team outbreaks to a compiled list already including nine reports: they detailed 57 NCAA collegiate athletes representing eight different institutions who were reported to have experienced ER. At least 51 of the afflicted athletes required hospitalization (11,30). Added to this list was a 10th outbreak in female volleyball players, and an 11th in female swimmers — both engaged in a novel conditioning workout. The swimmer ER cluster published by Stanfa et al. (10) is interesting in that the athletes had just competed in the League Championship meet followed by a 1-wk break from formalized training. The team then began off-season weightlifting sessions and 10 d into off-season training, the entire team, divided into small groups of three, participated in a novel arm competition workout. The competition workout consisted of completing the maximum number of pull-ups, rows, and bench presses for two complete cycles with a goal of beating the other groups. At the end of the competition, some swimmers completed a tiebreaker round while groups not finishing within the top two performed alternating pushups and standing with arms held horizontal and perpendicular to the floor. Three days after arm competition, four swimmers presented to the hospital emergency department (ED) with severe muscle pain, swelling, and dark-colored urine. Three were immediately admitted for treatment. Four days after arm competition, eight swimmers presented to the ED with similar symptoms; three were hospitalized for treatment. While the context was clearly created by the coaching and training staff, individual participation and effort also were critical. With regard to motivation in this cohort series, although not statistically significant, all six hospitalized swimmers reported they tried to “beat the other athletes” and exercised to “complete exhaustion.”
In addition to athletic team ER events, clusters have been described in both police and firefighter recruit training, youth correctional facilities, and the military. We examined an ER cluster among Reserve Officer Training Corps cadets who participated in a mandatory, timed, extreme conditioning program (ECP) workout (9). Forty-four cadets participated in this ECP; 11 were subsequently hospitalized with ER. Cadets completed the ECP workout as individuals or in teams. Nine (36%) of 25 individual and 2 (20%) of 10 team participants were hospitalized with ER. Among the cadets, no associations were noted between hospitalization for ER and finish time, previous fitness scores, or dietary supplement use. Most interestingly, the cadets had completed the event previously and without incident; however, the new variable induced by the leadership for this activity was the element of time and the influence of grading for merit. Contrary to reported ER risk factors, higher baseline fitness was not protective. Rather, cadet knowledge that performance was strongly linked to final cadet ranking greatly influenced intensity of effort.
Recent Inter-Association Task Force Guidance
A consistent focus of the NCAA has been the prevention of catastrophic injury and sudden death in collegiate athletes. One of the principal tools for data collection on these unique injuries has been the National Center for Catastrophic Sport Injury Research (NCSIR), founded at the University of North Carolina in 1982. Since 1970, in both high school and college football, nontraumatic fatalities have outnumbered traumatic fatalities. Nontraumatic deaths in American football have remained relatively steady for more than five decades. Data from 2017 reveal the current decade will continue this unfortunate and often preventable trend of nontraumatic deaths occurring largely in out-of-season or preseason workouts. From 2001 to 2017, the ratio of nontraumatic to traumatic death in college football was 5:1 — 35 nontraumatic deaths compared with seven traumatic fatalities (28).
In response to the aforementioned data, and previously described case series illustrating “team” exertional illness events, the NCAA Board of Governors unanimously endorsed comprehensive recommendations to prevent catastrophic injury and death in collegiate athletes. These recommendations, set forth in a document entitled Interassociation Recommendations: Prevention of Catastrophic Injury and Death in Collegiate Athletics, are the fourth and final product of the 2016 NCAA Safety in College Football summit (2). This document on prevention of catastrophic injury and death is the first to be endorsed under the Uniform Standard of Care Procedures. These recommendations provide a flexible roadmap for member schools to address catastrophic injury prevention in six key areas: sportsmanship; protective equipment, acclimatization and conditioning; emergency action plans; strength and conditioning personnel; and education and training. The document identifies significant responsibilities for leaders who train athletes. Concurrent with the NCAA document, the National Strength and Conditioning Association and Collegiate Strength and Conditioning Coaches Association published comparable guidance addressing transition periods (31).
A strong “callout” in this NCAA landmark document was the identification of unique periods of athlete vulnerability. The NCSIR data clearly identified the first week of transition as a period when many nontraumatic deaths and injuries occur. These transition periods are often associated with poor environmental acclimatization and reduced fitness levels in athletes returning to activity. The document formally identified both individual and team transition periods, generally a 7-d cycle. Individual transitions include athletes that are new to the program, returning after an injury or illness, and delayed participation relative to the team schedule. Team transitions include resumption of training after academic breaks (e.g., winter, spring, summer breaks). The NCAA document clearly identifies that during this time conditioning programs should be appropriately calibrated with appropriate work to rest cycles. The NCAA further states that at a minimum all strength and conditioning sessions, regardless of when in the year they occur, should be evidence- or consensus-based; sport-appropriate; intentionally administered; appropriately monitored, irrespective of the phase of training; and nonpunitive in nature. Finally, the NCAA recommendation requires that all training and conditioning programs be documented and approved by a certified strength and conditioning professional.
A Leadership Anecdote
The senior author (F.O.) recently had the opportunity to observe training at a large military post and witness the utilization of a newly installed arm immersion cooling system for the prevention of exertional heat illness in warfighters. The units were positioned at all training sites and trainees were encouraged to use the systems liberally. The brigade commander noted that one of four companies had a remarkably lower heat illness rate than the others. The commander followed all four companies to see if he could identify what variable was different because all units had the same equipment and comparable training loads. Importantly, he observed that three companies were reticent to use the new devices because many warriors did not want to be perceived as “soft.” One company, however, which was the unit with the lowest rate of illness, used the equipment for all warriors after each training iteration; this was at the direction of the unit's company commander. The next day, the brigade commander instituted a policy that all units would use the cooling system after each training iteration. The brigade commander thoughtfully and effectively balanced his own role as a follower and as a leader to minimize future cases of heat illness. He was an attentive “follower” when he observed and studied the situation and gathered information to determine a likely cause and effect relationship regarding the use of the immersion cooling system and heat illness. He was an effective “leader” when he instituted a policy regarding the use of the immersion cooling system for his followers.
Conclusion and Recommendations
In summary, we have provided cases to highlight risk factors for ERI, ranging from individual motivation to succeed or outperform, and environmental challenges to the character, context, competence, and communication of leaders and followers, as contributing to exertional events. Importantly, we have introduced the “leader-follower” framework as an additional lens for root cause analysis of ERI to improve effective prevention. Good leadership can be a strong countermeasure for setting the tone to prevent ERI and followers need to feel accountable to their leaders to also minimize the onset of any ERI. If we hope to clearly change the current slope of increasing ERI events, then the authors believe improvements will come in the form of leadership education and development for those who coach, train, and inspire both athletes and warfighters. In addition to education for leaders, athletes and warfighters have the additional responsibility as followers to be self-aware about variables (physical and psychological) relevant to their performance and health, acknowledge their role in ERI, and realize when they need to lead and communicate “up” and “sideways” to prevent ERI in themselves and their teammates. Medical leaders have a key role with coaches and athletes, and perhaps the greatest opportunity to make a difference. Safety and performance are team efforts!
The authors declare no conflict of interest and do not have any financial disclosures.
The information presented in this commentary represents the opinions of the authors and not those of the Department of Defense or the Uniformed Services University.
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