American College of Sports Medicine (ACSM) Expert Consensus Statements are documents created by consensus among a small group of recognized leaders in the field. These statements are designed to present existing knowledge, highlight knowledge gaps, and present recommendations for clinical practice. This present expert consensus statement updates and replaces the prior ACSM statement entitled “AHA/ACSM Joint Position Statement: Recommendations for Cardiovascular Screening, Staffing, and Emergency Policies at Health/Fitness Facilities,” which was published in June 1998 (1). Many aspects of this prior statement remain valid, specifically the emphasis on the health benefits of exercise and physical activity (PA), the value of a well-trained fitness facility staff, and the necessity of developing and practicing an emergency response plan. On the other hand, the prior statement emphasized providing “recommendations for cardiovascular screening of all persons (children, adolescents, and adults) before enrollment or participation in activities at health/fitness facilities.” The present consensus statement, in contrast, seeks to minimize screening and other factors that may impede the use or the availability of physical fitness facilities. This newer approach is based on four established concepts:
- 1) The increasingly recognized health benefits of even low levels of PA (2).
- 2) The rarity of cardiovascular events provoked by PA among apparently healthy adults (3), even among those with established cardiovascular disease (CVD) (4).
- 3) The recognition that preexercise screening strategies are a barrier to PA because they often require additional medical testing for clearance (5).
- 4) The recognition that immediate assistance provided by nonmedical personnel, such as dialing 911, initiating bystander cardiopulmonary resuscitation (CPR), and using an automated external defibrillator (AED) can greatly reduce the morbidity and mortality of acute cardiac events.
This updated document seeks to provide suggestions and guidance on establishing emergency policies and plans for a variety of exercise settings including professionally staffed fitness facilities, unstaffed facilities, such as community recreation and hotel fitness facilities, and sporting event venues, such as school athletic facilities. It is beyond the scope of this document to address specifically all types of exercise facilities so this statement emphasizes general safety recommendations based, in part, on the comprehensive recommendations for emergency planning and policies available from prior ACSM publications (6).
The Importance of PA and Cardiorespiratory Fitness in Health and Longevity
Regular PA provides significant health and longevity benefits for all participant groups as detailed by the second edition of the U.S. Department of Health and Human Services PA Guidelines for Americans released in 2018 (7). These updated guidelines are based on the PA Guidelines Advisory Committee's Scientific Report (PAGAC), which reviewed and summarized the current body of scientific evidence supporting the value of PA for human health and function (8).
The list of health benefits attributable to PA has expanded significantly since the original 2008 PA Guidelines. The 2018 PAGAC Scientific Report identified a direct relationship between sedentary behavior and all-cause mortality, incidence and mortality of CVD, incidence of type 2 diabetes, as well as incidence of endometrial, colon, and lung cancer (9–11). The report also demonstrated that mortality risk increases progressively with increased sitting time. This risk is attenuated with increased volumes of moderate to vigorous PA (MVPA), with the highest levels of MVPA affording the greatest risk reduction (12). In addition to these findings, the PAGAC Scientific Report (7,8) also provided strong evidence for the following:
- –Greater volumes of MVPA are associated with reduced risk of excessive weight gain and obesity in adults and children.
- –More physically active pregnant women are less likely to gain excessive weight in pregnancy and are less likely to develop gestational diabetes or postpartum depression than their less active peers.
- –Greater volumes of PA are associated with a reduced risk of dementia and improve other aspects of cognitive function (7,8).
- –PA reduces the risk of falls and fall-related injuries in older adults. The 2008 report noted that MVPA reduced breast and colon cancer risk. The 2018 report expanded the type of cancers whose risk was reduced with MVPA to include endometrial, esophageal, kidney, lung, stomach, and bladder cancers. The 2018 report also concluded that for individuals with the most common, noncommunicable chronic conditions such as osteoarthritis, hypertension, and type 2 diabetes, regular PA could reduce the risk of developing a new chronic condition, reduce the risk of progression of an existing chronic condition, and improve quality of life and physical function.
Exercise and regular PA have long been known to decrease established CVD risk factors (5,13). Exercise has positive effects on lipoprotein profiles, blood pressure, C-reactive protein, insulin sensitivity, and may play an important role in weight management. Healthy middle-aged and older adults with greater cardiorespiratory fitness at baseline, and those who improve their cardiorespiratory fitness over time, have a lower all-cause and CVD morbidity and mortality. There also is a decreased risk of clinical events associated with greater cardiorespiratory fitness in those with preexisting CVD (5,7,13). Epidemiological studies have shown that 150 min·wk−1 of moderate PA or 75 min of vigorous PA are associated with decreased rates of CVD and premature mortality (5,13). Significant reductions in CVD and premature mortality occur at PA volumes well below these targets, starting at even half of the recommended volume (14).
Data support the target PA goal of 150 to 300 min·wk−1 of MVPA, but the 2018 guidelines highlight that there are health benefits associated with any level of PA (7). For those individuals who perform little to no MVPA, even replacing sedentary behavior with light-intensity PA reduces the risk of all-cause mortality, CVD incidence and mortality, and the incidence of type 2 diabetes (7). A pooled analysis of six prospective cohort studies on the association between leisure time activity and mortality risk demonstrated that there is neither an upper nor lower threshold for these benefits to occur (15). The greatest benefits are seen with the initiation of MVPA, and there is no increased mortality risk at activity volumes up to four times the current guideline amounts. Also, at least 70% of the maximal benefit is achieved by meeting current MVPA guidelines of 150 min·wk−1 (15). The 2008 Guidelines concluded that health benefits only accrued with at least 10 min of continuous MVPA, but the 2018 Committee concluded that every minute of MVPA counts toward the goal (16–18). These findings provide the public with various options on how to achieve their PA goals.
The Cardiovascular Risks of PA
Although habitual PA reduces the risk of CVD, vigorous PA (defined as ≥60% of functional capacity or ≥6 metabolic equivalents [METs; 1 MET = 3.5 mL O2·kg−1·min−1]) acutely increases the risk of sudden cardiac death (SCD), acute myocardial infarction (AMI), and hemorrhagic (19) and ischemic stroke (20). Possible triggering mechanisms for plaque rupture and acute coronary thrombosis (Table 1) (21) or threatening ventricular arrhythmias have been suggested (Fig. 1) (23).
An increase in platelet aggregation, which may initiate or contribute to coronary thrombosis, has been reported in habitually sedentary individuals who engaged in unaccustomed high-intensity PA, but not in physically trained individuals (24).
The pathology of exertion-related acute cardiovascular events varies with the victim's age. Structural cardiovascular abnormalities, most notably, hypertrophic cardiomyopathy (HCM) and high-risk congenital anomalous coronary anatomy, are commonly cited causes of SCD in younger persons, although recent autopsy studies of exercise-related SCD in high school and college athletes have identified no structural cause at autopsy, a condition called either sudden arrhythmic death syndrome (25) or SCD with a structurally normal heart (26). A study of athletic participants aged 12 to 45 years reported 74 cases of sudden cardiac arrest (SCA) during 18.5 million person-years of observation, yielding an incidence of 0.76 cases per 100,000 athletes per year (27). Of these cases, 16 occurred during competitive sports, of which 44% survived, whereas the remaining 58 occurred during noncompetitive sports, of which 44% also survived. In contrast to previous studies which identified HCM as the primary cause of SCD in young athletes (28), genetic structural abnormalities, such as HCM and arrhythmogenic right ventricular cardiomyopathy, caused only 8% and 5% of the SCAs, respectively (27).
Atherosclerotic CVD is the most common autopsy finding in individuals older than 40 years who experience SCA and SCD during or immediately after strenuous exercise (29). Nevertheless, the routine referral of asymptomatic middle-aged and older individuals for medical clearance before starting an exercise program appears unwarranted and presents needless barriers to exercise adoption (30,31). On the other hand, physically inactive individuals with known cardiovascular, metabolic or renal disease, or signs/symptoms that are suggestive of these diseases should seek medical attention before starting an exercise program, regardless of the intensity (5).
A study of nontraumatic sports deaths in 126 high school athletes (115 men and 11 women) and 34 college athletes (31 men and 3 women) over 10 years found that estimated death rates were five-fold higher in male athletes than in female athletes (32). The incidence of exertion-related SCD and AMI also is lower in women than men. The risk of SCD during or immediately after exercise is 15-fold to 20-fold higher in men, a rate much higher than the two-fold to three-fold higher male SCD rate reported in epidemiologic studies not limited to exercise (33). The rate of SCA during full and half marathon running also is higher among men than women (0.90 vs 0.16 per 100,000) (34). The absolute incidence of exercise associated AMI also is slightly higher in men versus women, 0.046 versus 0.015 person hours (35); however, most studies have not found a sex difference in the relative risk (RR) of myocardial infarction during physical exertion (33).
The incidence of cardiovascular events during very light- to moderate-intensity PA is extremely low and similar to that reported under resting conditions. However, vigorous PA, especially when sudden, sporadic, or involving high levels of anaerobic metabolism, does transiently increase the risk for AMI and SCD in susceptible individuals (36). Additional modulators of exercise risk may include superimposed environmental stress, including heat/humidity (37), cold (38), water immersion (39), altitude (40,41), as well as the excitement of competition (42). These accentuate the cardiac and respiratory responses to exercise, and thereby increase the risk of exertion-related acute cardiac events.
The rate of exercise-related AMI and SCD is extremely low whether estimated as events per participant or per hour of exercise. The death rate for joggers is approximately one jogging death per year for every 7620 middle-aged joggers in Rhode Island, corresponding to approximately one death per 396,000 h of jogging (43), although this rate was 7.6 times the hourly death rate during less strenuous activities. Vigorous recreational PA is associated with one nonfatal and one fatal event per 1,124,200 and 886,526 h of participation, respectively (44). The incidence of exercise-related cardiovascular events at YMCA sports centers has been estimated at one death per 2,897,057 person-hours, although exercise intensity was not reported (45). The rate of exercise-related nonfatal and fatal cardiovascular events in apparently healthy adults from fitness facilities also is low at one per 1,124,200 and one per 887,526 person hours, respectively (46). Two studies (47,48) and a related review (49) suggest that vigorous PA transiently increases the combined RR of AMI and SCD approximately two-fold to 107-fold compared with nonvigorous exercise or rest, and that the RR decreases with increasing frequency of regular vigorous exercise (Fig. 2) (30,47).
Nevertheless and despite the increased RR, the absolute risk of these events remains low and between 1 per 565,000 (50) and 1 per 2,600,000 h of exercise (49). The Physicians' Health Study (51) and Nurses' Health Study (52) reported only one SCD per 1.5 million hours of vigorous PA in men and per 36.5 million hours of MVPA in women. In aggregate, these studies highlight the rarity of cardiovascular complications during exercise and suggest that exercise is safe for most individuals. Some authors have presented a profile of the individual at increased risk for exercise-related acute cardiovascular events (Table 2) (35,53).
Exertion-related acute cardiovascular events are often preceded by warning signs or symptoms (54,55), which should prompt immediate cessation of exercise training and medical review (5,36).
Risk of High-intensity Interval Training
There is growing evidence that high-intensity interval training (HIIT) provides comparable or even greater increases in exercise capacity compared with moderate-intensity continuous aerobic exercise training (MICT) in persons with and without chronic disease. HIIT refers to the combination of high-intensity exercise usually lasting 2 to 5 min with periods of moderate or recovery exercise during the same exercise workout. There are many different forms of HIIT which can vary in the duration and intensity of both the high-intensity and recovery periods.
However, there is understandable concern about the safety of HIIT in adults with known or occult coronary artery disease (CAD). A comparison of cardiovascular event rates during HIIT versus MICT in 4846 patients undergoing exercise-based cardiac rehabilitation (CR), involving 175,820 training hours, revealed event rates of 1 per 23,182 patient-hours and 1 per 129,182 patient-hours, respectively, a nearly six-fold higher risk for with HIIT, but there were only three events (1 fatal cardiac arrest during MICT and 2 nonfatal cardiac arrests during HIIT) (56). These low event rates preclude definitive quantitative determination of the risk associated with HIIT.
More recently, a systematic review examined the cardiovascular complications associated with HIIT conducted in CR sites for patients with CAD or heart failure (57). Based on 23 studies involving 547 participants completing 17,083 HIIT sessions (equivalent to 11,333 training hours), there was only one major, nonfatal cardiovascular event. Another systematic review of 17 studies within medically supervised CR settings, including 465 and 488 patients undergoing HIIT and MICT, respectively, reported no deaths or cardiac events requiring hospitalization among both groups (58). Although HIIT appears to provide a time-efficient alternative to MICT, additional long-term studies assessing the safety of HIIT are needed before it can be widely adopted in individuals with known or suspected CAD, especially in unsupervised, nonmedical settings (59).
Numerous epidemiologic studies have shown that low-fit individuals are approximately two to three times more likely to die during follow-up as compared with their more fit counterparts, regardless of the risk factor profile (60–62) or the presence of subclinical CAD as indicated by coronary artery calcium (63). To put these data in perspective, it is important to consider that the absolute risk associated with each bout of exercise is extremely low, the RR is inversely related to the habitual level of PA, and that regular exercise, including high-volume endurance activity (>1 h·d−1) (64), reduces the long-term risk of acute cardiovascular events by up to 50% (65). Accordingly, a habitually sedentary lifestyle appears to be far riskier than a physically active one. Given the likely benefits of improved cardiorespiratory fitness and chronic moderate- to vigorous-intensity exercise in reducing cardiovascular events, it is probably more important that individuals exercise regularly at a convenient time of day, regardless of the hour (36).
Acute exercise-related cardiovascular events, while representing potentially catastrophic complications, are far less common than sports and recreational musculoskeletal injuries, such as strains, sprains, and fractures (22,66). Fortunately, regular emergency drills, immediate cardiopulmonary resuscitation, and the use of AEDs have increased SCA/SCD survival rates in the general (67) and running populations (68).
Cardiovascular Screening of Prospective Members/Users
Health clubs and fitness facilities attract people representing the entire spectrum of health, including individuals with established and occult CVD. Accordingly, a multifactorial approach, including preparticipation screening (PPCS), is of paramount importance to maximize safety in these environments. PPCS has been proposed as a tool capable of identifying people at high risk for adverse CV events during exercise, thereby providing an opportunity for subsequent disease diagnosis and management with attendant risk reduction.
The absolute risk of AMI and/or SCD during exercise is variable and is determined by several key factors. There is a clear sex predilection with males approximately 10-fold more likely to experience an adverse CV event during exercise (34). Data from the U.S. military demonstrate a clear relationship between increasing age and SCA incidence driven largely by age-related increases in the prevalence of atherosclerotic coronary disease (69). PA habits also are an important determinant of risk. Siscovick et al. (70) demonstrated a strong inverse relationship between risk of sudden death and hours per week of PA among men without known heart disease. The presence of non-CVD diseases, specifically diabetes and renal disease, due in part to their pathogenic association with atherosclerotic CAD, appears to increase the risk of adverse events during exercise (47,51). Specific types of PA have been associated with higher risks of SCA. Team sports, such as basketball, soccer, and football, appear to confer the highest-risk profile both among young competitive athletes (71) and recreational fitness facility attendees (72).
All facilities offering exercise equipment, services, classes, and/or instruction should conduct cardiovascular screening of all new members and prospective users. The ACSM advocates for PPCS among adults and guidelines for this practice have been published (5). The primary goal of PPCS is to identify new members or users of a health or fitness facility that should be directed for formal medical evaluation prior to initiation of exercise. Historically, the approach to PPCS included characterization of baseline PA habits followed by ascertainment of CVD risk factors, established diseases, and symptoms suggestive of occult CVD. However, CVD risk factor characterization has been removed from the most recent ACSM PPCS algorithm due to its low specificity for the detection of clinically relevant disease (Fig. 3) (5). The contemporary ACSM PPCS algorithm has thus been simplified to include: 1) a determination of habitual exercise habits; 2) the identification of established CV, metabolic, and renal diseases; 3) and the recognition of signs and symptoms of potential occult CVD. This approach is feasible for use in health and fitness facilities as its use does not require on-site medical expertise, but does required trained staff and appropriate supervision. Accordingly, PPCS should be performed for new members and prospective users of these facilities at the time of enrollment following an informed consent process with subsequent facility access granted or withheld pending the need for medical clearance. Among children embarking on an exercise program and young competitive athletes, alternative approaches to PPCS as recommended by the American College of Cardiology/American Heart Association (AHA) may be more appropriate (73). While numerous studies have shown that PPCS can and does detect underlying CV diseases, its efficacy for the reduction of adverse CV events during exercise has yet to be firmly established.
General Recommendations for All Facilities
A well-organized emergency response system is critical to providing a safe environment for exercise participants. Preventive measures including proper signage, ongoing surveillance of facility safety and member education also are part of a comprehensive risk management plan. The following section provides recommendations based on the standards set forth by ACSM's Health/Fitness Facility Standards and Guidelines (6) to prevent and respond to cardiovascular emergencies. Understanding that health and fitness facilities vary greatly in their scope of offerings and clientele, the following are considered the most crucial elements that need to be incorporated at a level appropriate for each facility. Further details and examples can be found in the text referenced above.
Emergency response system
Health/fitness facilities must have a written emergency response policies and procedure plan that is reviewed quarterly and physically rehearsed a minimum of twice annually. These policies enable staff to respond to basic first-aid and other emergency events in an appropriate and timely manner. The emergency response system must address medical emergencies that are reasonably foreseeable in an exercise setting including common orthopedic injuries, SCA, AMI, stroke, hypoglycemia, and heat illness. The plan must provide specific instructions for how an emergency situation is handled by the staff and provide the location of all emergency equipment, including AEDs, the phone, and the entry/exit locations for access by emergency medical services (EMS) personnel. Facilities are encouraged to approach local health care or EMS personnel to assist with development or to review the emergency response system plan.
To reduce the frequency of emergency situations, a safety audit should be regularly conducted on all areas of a facility to reduce potential hazards. While prevention of emergency situations is ideal, a high level of overall emergency readiness is critical as exercise facilities by nature have risk. Staff training and preparation is vitally important. All staff members should have the opportunity to receive training and certification in first aid, CPR, and AED usage. To assure the ability to provide an adequate response to an emergency situation, first-aid kits and other medical equipment, including AEDs, should be regularly inspected and maintained. Telephones or other emergency communication devices should be readily available and telephone numbers for emergency assistance should be posted on or near the telephone. A capable staff member should be designated to serve as the program coordinator with ultimate responsibility for the facility's overall level of emergency readiness.
Written documentation is a crucial element of a comprehensive emergency response plan. Important documents, including records of staff training, recertification, and the written emergency plan, should be kept in an area that is easily accessed by the staff. An incident report system should be in place (Table 3).
If an incident occurs, written documentation should be completed in a timely fashion with the advice of legal counsel and maintained on file in accordance with the statute of limitations for where the facility is located or as advised by legal counsel.
Automatic external defibrillators
AEDs are sophisticated, computerized devices that provide voice and visual cues to guide exercise professionals and bystanders to defibrillate pulseless ventricular tachycardia/fibrillation (VT/VF). AEDs detect life-threatening cardiac arrhythmias and then administer an electrical shock that can restore normal sinus rhythm. Defibrillation is the passage of an electrical current across the myocardium of sufficient magnitude to depolarize a critical mass of myocardium and to restore coordinated electrical activity (74). Early defibrillation is critical for successful survival of VF, the most frequent type of SCD. Electrical defibrillation is the only effective treatment of VF and delaying defibrillation rapidly reduces survival and increases the chance of neurological defects if the patient does survive. In the absence of bystander CPR, survival rates after witnessed VF decrease 10% to 12% with every minute of delay in defibrillation (75,76). When bystander CPR is provided, the decrease in survival averages 3% to 4% per minute from collapse to defibrillation (75,76). According to the AHA, immediate recognition of SCA and activation of the EMS, early CPR with an emphasis on chest compressions, and rapid defibrillation with an AED are the three most important components that must occur within the initial moments of cardiac arrest (77).
Health/fitness facilities must comply with federal, state, and local requirements relating to AEDs and must include a public access defibrillation program as part of their written emergency response policies and procedures. AEDs can be operated by laypeople with minimal training, making them an important resource in both unstaffed and staffed facilities.
Every site with an AED should strive to get the response time from collapse caused by cardiac arrest to defibrillation to 3 min (optimal) to 5 min (acceptable) or less because survival of VT is highest when CPR is delivered and defibrillation is attempted within 3 to 5 min (78–81). The goal of a 3-min response time can be used to help determine the optimal number and placement of AEDs. The best means of achieving the recommended response time is to provide AEDs in visible and accessible locations that the staff or public can reach within a 1.5-min walk. Facilities with multiple floors should consider locating an AED on each floor. The AED should be inspected and maintained according to manufacturer's specifications on a daily, weekly, monthly, or as-needed basis, and all related information should be carefully documented and maintained as a part of the facility's emergency response system records. The emergency plan and AED plan should be coordinated with the local EMS provider, a prerequisite required by some states.
Staffed exercise facilities should have at least one staff member who is currently trained and certified in CPR and in the use of an AED on duty during all operating hours (6). Unstaffed facilities must have a public access defibrillator program in which either a fitness center member or external emergency responder can respond from the time of collapse to defibrillation in 5 min or less (6).
The Food and Drug Administration may require that a physician prescribe an AED before it can be purchased. The AHA strongly recommends that a physician, licensed to practice medicine in the community in which the exercise facility is located, provide oversight to the facility's emergency response system and AED program. The physician can assume multiple roles, such as prescribing and selecting the AED, ensuring compliance with all relevant statutes and regulations, reviewing and approving the emergency and AED plan, attending and documenting at least one rehearsal of the emergency plan and providing standing orders for use of the AED (6). All incidences involving the use of the AED must be recorded and reported to the physician who is providing oversight within 24 h.
Staff credentials and training
Health fitness facility staff should be appropriately trained and certified by an accredited organization that offers a basic life support (BLS) course incorporating CPR and AED. These courses should include a hands-on practical skills assessment. The AHA and American Red Cross provide BLS training and certification that typically lasts for 1 to 2 years. However, since CPR and AED skills erode after training, retraining or practice sessions should be conducted at least every 6 months. Copies of all staff credentials and documentation of additional retraining should be kept on file and regularly reviewed to assure all certifications are up to date. Staff should be encouraged to attend conferences and engage in other forms of continuing education that address emergency response and overall risk management.
Numerous certifying organizations exist to educate and ensure qualified exercise professionals. While some health fitness certifications are highly rigorous, require knowledge of first aid, preparticipation health screening and injury prevention and require current CPR/AED certification, other certifications require minimal training and have no prerequisites. Because there is no regulation of fitness certifications, attention must be paid to the credentials and qualifications of fitness center employees. Certification programs that do not require CPR/AED certification or do not provide training related to risk management should be considered inadequate.
Health/fitness facilities should post signage indicating the location of any AED and first-aid kits, including directions on how to access those locations. The signage should have the proper appearance, readability, and placement to clearly display the information in a manner that can easily be understood by members and users. There also should be signage on the emergency plan, whom to contact, and how to use the AED, especially in facilities, such as hotel fitness centers that are not staffed.
Health/fitness facility members and users can play a significant role in the prompt response to cardiovascular emergencies. Members should be taught signs and symptoms of untoward CVD events and be encouraged to learn and practice basic bystander CPR. Further, members should be provided with information about the location of emergency telephones and AEDs during orientation to the facility. This information can be provided didactically or in writing. Additional attention to member training is essential at unstaffed facilities where an emergency may require the help of a member. Having video surveillance and/or a panic button to activate EMS also should be a consideration in facilities that do not have staff onsite.
Mass Participation Sporting Events and Venues
The general facility recommendations provided above apply to mass participation sport events such as large city marathons and public sporting venues such as stadiums and arenas. All staff should receive training in first-aid, CPR, and AED use. A dedicated on-site medical staff with full emergency response capability represents contemporary standard of care. A comprehensive emergency action plan with input from local and regional civil services (i.e., police, fire, EMS, proximate hospitals) must be developed and rehearsed. Additional considerations for these environments involve contingency planning for sudden inclement weather, loss of electricity, and mass casualty situations.
This ACSM Expert Consensus Statement replaces the 1998 AHA/ACSM Joint Position Statement that provided recommendations for enhancing the cardiovascular safety of health and fitness facilities (1). The present document emphasizes the importance of staff training, the development of facility emergency plans, and the practice of emergency procedures. The ultimate goals of this document are to reduce further the rare cardiovascular complications of exercise while removing unnecessary barriers to widespread participation in an active lifestyle.
Click here (http://links.lww.com/CSMR/A64) to download a PowerPoint presentation that summarizes this ACSM Expert Consensus Statement for classroom or other presentation uses.
The authors declare no conflict of interest and do not have any financial disclosures.
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