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Editor’s Note: This Best Practice Guide was contributed by William O Roberts MD, MS, FACSM, FAAFP. Dr. Roberts is a Professor and the Director of Faculty Affairs in the Department of Family Medicine and Community Health at the University of Minnesota in Minneapolis, Minn. He also serves as the Medical Director for the annual Medtronic Twin Cities Marathon in Minneapolis, and in that role has developed his expertise in medical operations for road races. The medical care plan for road races can vary from simple to complex. Larger races are set up to deliver onsite care to reduce the patient load on the community medical system and have systems in place to respond to life-threatening medial problems. All races, including smaller races, should develop a medical plan for runner safety that has a written set of safety parameters agreed upon in advance with contingencies for heat, lightning, high winds, cold, and other safety concerns. The plan should include a specific emergency action plan (EAP) for rapid response to life threatening problems. From 5K to 100K, the causes of runner collapse are similar, but the list of life-threatening medical problems changes with increasing distance and increasing heat stress. Injury and Illness in Road Racing The race team medical protocols should address both the serious and common medical problems that confront runners in each event. The basic differential diagnosis for the runner collapse is: • Sudden cardiac arrest • Exertional heat stroke • Exercise associated hyponatremia • Anaphylaxis • Insulin shock • Asthma • Exercise associated collapse (exercise associated postural hypotension) Exercise associated collapse is by far the most common of these problems and is essentially a “diagnosis” of exclusion. Exercise associated collapse or exercise associated postural hypotension also tends to occur more frequently in hot and humid conditions and in longer races. Although runners may appear in distress, this problem responds to leg elevation in the supine position or if the runner can stay upright, assisted walking. This is a diagnosis of exclusion and the runner should have a good heart beat, be breathing well, and be able to answer simple questions. Other far less common, but potentially fatal causes of runner collapse are sudden cardiac arrest, exertional heat stroke, and exercise associated hyponatremia. Hypothermia (decrease in serum sodium concentration caused by excessive water intake) also occurs in cool weather races, especially if associated with rain. Dehydration is not very common in road races where water is readily accessible but can occur and is often incorrectly assumed to be the cause of runner collapse. Injuries and illness can occur at any point along a race course. Over time races learn their trouble spots, like the top of a long hill climb or the bottom of a long downhill segment. The finish area tends to have the most medical encounters as runners stop or slow, and the physical toll of the race begins to show. Most problems are short lived and time limited. Factors that influence medical encounter rates include race day weather, event distance, event type, and the health, fitness, and acclimatization of participants. It is clear from anecdotes and case reports that when weather conditions are warmer and more humid than the area averages and recent actual weather conditions, the risk of EAC, EAH, EHS, and race dropouts along the course increase. In general, the higher the wet bulb globe temperature (WBGT) conditions (high humidity and above normal for season temperatures) the greater the number medical encounters, race drop outs (before and during the race), and both exertional heat stroke and exercise associated hyponatremia cases. Medical encounters increase with the race distance, hot and humid weather, and cold and rainy weather. Marathon (42K/26.2 miles) finish line encounter rates vary from 1-6% of finishers at the Medtronic Twin Cities Marathon and have been as high as 10% in hot, humid conditions at other marathon races. On average, the number of starters who do not finish plus the number of medical encounters per 1000 finishers at the Twin Cities Marathon rises from 40-60 in cool (start WBGT 30-55° F) conditions to 160 in warmer conditions (start WBGT 72°F). The Army 10 Miler, held each October in Washington D.C., has about 4 medical encounters per 1000 starters, but on two recent hot and humid race days had runners experience 30 exertional heat strokes. Runners with heat stroke require immediate care involving 2-5 medical providers for 20-60 minutes, so treating 30 heat stroke casualties on site in a short time span will involve 60 to 90 volunteers. In cool weather conditions most participants who start a marathon or other distance race will finish, but the combination of cold and rain also increases race drop outs and finish area medical encounters. Sudden Death and Cardiac Arrest Runner related deaths are usually due to cardiac arrest (SCA), exertional heat stroke (EHS), or exercise associated hyponatremia (EAH). Sudden cardiac arrest in the marathon is the most studied, ranging from 1-3 per 100,000 finishers with about half saved by rapid response teams using CPR and defibrillation. The emergence of portable and easily applied automatic external defibrillators (AED) has improved the risk profile for participants of mass participation events. Mobile teams on bicycles or carts equipped with AEDs that can rapidly move along the course are key to reducing time to defibrillation. Teaching hands-only CPR to non-medical volunteers, runners, and spectators may also improve outcomes with more people available to initiate CPR. The most likely first responder to a collapsed runner will be another runner in the race. All races should be prepared to address cardiac arrest. Most community recreational events will involve older participants who are at more risk for sudden cardiac arrest. The risk for cardiac risk may be greater in high heat conditions as removing heat from the body increases cardiac demands. Integrating the emergency response system into the medical is essential for rapid response to runners who collapse from cardiac issues. SCA requires immediate transfer to an appropriate cardiac care center. In cardiac arrest cases, the initial response plan is to activate the emergency medical system, start hands only CPR, and apply an automatic external defibrillator as soon as possible. It is the lifesaving electric shock from a defibrillator that has the greatest impact on survival. Although cardiac arrest seems to be a finish line problem, an arrest can occur at any location along a race course and at any race distance. Survival is highly correlated with defibrillation and the advancing technology has made automatic external defibrillators readily available and relatively inexpensive. It is important to set up a system to access runners stricken by cardiac arrest with a defibrillator as rapidly as possible. At Twin Cities Marathon, we use bike teams and golf carts to shadow the runners along the course. An AED at the finish area is also an important asset. EHS and EAH are life threatening emergencies that can be treated onsite (treat first, transfer later). EHS is about 10 times and EAH is about 4 times more common than SCA in hot weather races. On site care can avoid delayed diagnosis and treatment in an emergency department and shave critical minutes off the time to treatment. Emergency departments may not have the necessary equipment and supplies for rapid treatment readily available or delays in treatment may occur while protocol-based imaging studies are obtained. Working with the community emergency medicine resources can help avoid treatment delays in participants who do not present to the event medical facilities but enter the medical care system through ambulance transfer or after the race has completed is critical to runner safety. EHS and EAH have the potential for full recovery if recognized and treated immediately. The local EMS providers and hospitals should be aware of your event and if there are over 1000 participants, an on-site ambulance is probably prudent. Notifying area emergency facilities in advance of your event and potential casualty types will allow time to adjust race day evaluation and protocols and increase staffing on race day to accommodate the anticipated increase in patient care volume. General Medical Problems Runners most often seek care in three basic categories: medical, musculoskeletal, and dermatologic. There is a very small percentage of serious medical problems including cardiac arrest, acute coronary syndrome, EHS, EAC, anaphylaxis, insulin reaction, and completed stress fractures where immediate intervention can reduce morbidity and mortality. The remainder of the medical issues are generally non-life threatening and self-limited but require intervention to resolve the issue and keep the patient load off the community emergency medical system. The most common medical condition following endurance activity is exercise associated collapse (EAC) or exercise associated postural hypotension (EAPH), which is usually self-limited and resolves spontaneously with rest and leg elevation. This accounts for 60% of the medical encounters and 90% of the encounters that were not related to musculoskeletal or skin issues at Twin Cities Marathon and is the leading cause for evaluation in the finish line medical tent. The subset of musculoskeletal conditions is mainly sprains and strains with occasional stress fractures and aggravated tendinopathies. Blisters and abrasions make up the bulk of skin issues. The distribution of injury and medical issues vary by event length with short distances having the least number of medical issues. Using medical protocol algorithms to standardize care among clinical staff will make the delivery of care more efficient and should improve outcomes. The basic medical evaluation of a collapsed runner is to look for spontaneous breathing, high rectal temperature, low serum sodium (in longer duration events), signs of anaphylaxis (facial, tongue, or throat swelling or restricted breathing, medical alert tags for chronic disease, and improvement with legs elevated. Putting the athlete in the “feet up” position at the start of the evaluation will begin the redistribution of fluid to the core and speed recovery for EAPH. Who Gets an IV in the Field? Intravenous fluids are rarely needed in the management of collapsed runners except for the very small number of serious medical problems. Over 12 years of finish line care at the Twin Cities Marathon, there were only 106 IV starts for 81,300 finishers. The main reasons to start an IV are fluid replacement or medication access. The following table outlines the criteria we use for starting an IV at Twin Cities in Motion events. The number of IVs started will likely vary with the training of the physicians and the comfort with the presentation of “collapsed” endurance athletes; physicians with less experience tend to start more IVs, so close supervision by experienced staff will reduce unnecessary IV starts. Fluid replacement Hypoglycemia (<60) After leg elevation 10-30 min with limited resolution Anorexia (lack of thirst or hunger) Orthostatic BP drop after leg elevation Vomiting or nausea BP < 100 sys & symptomatic Diarrhea Temp >104 or <95 and not responding to treatment Confused Severe muscle cramps or spasms “Not doing well”   Disposition and Discharge Criteria The disposition and discharge criteria should be determined in advance of the event by the medical team. At TCM events, we discharge runners when they are clinically stable, have a normal rectal temperature, and can walk without assistance. The first stage following recovery from self-limited EAPH collapse is the “sit test,” which involves moving the patient to the sitting position to check for an orthostatic reaction. If this change is tolerated, the next move is to stand up, and if tolerated, walking. Before departing the onsite treatment area, the runner is given our written discharge instructions that discuss continued fluid and energy replacement, the criteria for reevaluation, and follow-up recommendations. Ideally the runner is handed off personally to family or friends as part of the transition out of the medical area. Runners with more severe problems or not responding to the usual treatment protocols are transferred to an emergency facility. Runners with cardiac chest pain or acute coronary syndromes, shock, blunt trauma, initial rectal temperature <92ºF meet our criteria for automatic transfer. However, those with EHS are cooled first and then transferred unless they are clinically unstable or in cardiac arrest. Mass Participation Event Planning Every race should have and emergency action plan (EAP) that is integrated into the community emergency response protocol. A comprehensive EAP will leave the emergency departments and emergency transport systems available for the community and the event participants truly in need of advanced care. These “planned disasters” are convenient community disaster training experiences for future disasters that may confront a community. The International Institute of Race Medicine has race management materials and a race medicine handbook to assist races with protocols to improve or develop race medical care teams. The medical plan should include education for the medical and general race volunteers so all are using the same protocols and have the same expectations. This is especially important when it comes to unexpectedly hot weather and expectations for runner fluid consumption during the race. Education during in-person race and medical team meetings, with written materials, and/or via web-based modules outlining both the medical risks and the evaluation and management protocols will improve the care on race day. The EAP should address all potential adverse events that can alter the race including high heat and humidity, severe storms, lightning, high wind, freezing rain, terrorism or threat of terrorism, vehicles infringing upon the course, potentially dangerous animals, and political demonstrations. All have disrupted or cancelled events around the world.   Planning in close cooperation with the community emergency personnel allows a rapid transition in the chain command in the face of natural or man-made disasters. Many communities require integrating public safety and emergency medical responders, law enforcement, public health and homeland security into the emergency response plan as a part   of the event permitting system. The idea that nothing will cancel or modify an event for runner safety has largely disappeared from road racing administration lore, with cancellations of major events at the hands of nature (in the wake of a hurricane, heat, and lightning storms) and unfortunately at the hands of man (terrorist bombing – Boston Marathon 2013). Events must also determine the community medical capacity to care for event casualties in addition to the emergency needs of the community. Planning is important to ensure that a high volume of race medical incidents will not disrupt routine or emergency community care. Preparation for an event medical team will depend on location, race distance, number of participants, and the most likely injuries and medical problems. Establishing a medical team that can respond to the worst-case race casualty scenario will improve the safety profile for the participants and not force medical volunteers to overextend their care capacity or to work above their medical license and training.   Race planning should start 6-12 months prior to the race to develop medical protocols, supply and equipment lists, personnel needs, communication protocols, rapid medical response plans, disaster (crisis) plans, cancellation parameters, a heat ramp up plan, participant and volunteer education materials, and volunteer recruiting plans. On race day, the decision to start the race should be based on safety parameters determined in advance by the race and medical committees. After the race, a post-event report outlining what went right, what went wrong, and what can fix the problem(s) will help with planning for the next race.   A medical director (MD/DO) with an interest in race medicine can help organize the medical team and develop the medical protocols. A medical coordinator with an allied health background can be an asset to the medical and race management teams, fulfilling many of the administrative functions and leaving the medical director to deal with medical protocols and race safety issues. The medical director must be a part of the race management decision making process and should sit on the executive administration committee to represent the participant safety and medical interests. The medical director and team, in cooperation with the race administration should address the following areas in preparation for race day. Race volunteer safety should also be considered in the race plan.   Competitor and volunteer safety Transportation Competitor and volunteer education Communications Race scheduling Fluids & foods Start time Equipment Hazardous conditions Supplies Impaired competitor policy Medical & race records Emergency facility notification Medical protocols Pre-race health evaluation plan Medical pathogen precaution protocol   Course medical care Adverse event protocol Family waiting Disaster or adverse event counseling   Assembling a Medical Team, Use of Volunteers An interdisciplinary medical team of physicians, physicians in training (residents and medical students), physician-extenders (physician’s assistants and nurse practitioners), athletic trainers, physical therapists, registered nurses (especially from emergency departments, intensive care units, and cardiac care units), paramedics, emergency medical technicians, first aid providers, and students than can assess and manage medical, musculoskeletal, skin, and sometimes trauma issues that arise during and after races. Non-medically trained volunteers can help with tent set up and organization, equipment and supply management, scribe for medical record completion, retrieve clothing bags, and other functions that do not require medical training. Volunteers shift length in the 4-6 hour range is reasonable, and longer shifts lead to fatigue and attrition. Medical volunteers should be readily identifiable to participants and other race volunteers. A distinctive T-shirt, jackets, vests, and/or hats work well and provide a thank you gift for each volunteer that doubles as a marketing tool for future races. The number of volunteers needed to provide adequate care during the race will depend on the number of entrants, the length of the race, the anticipated encounter rate, and the peak finisher flow. Peak finisher flow often correlates with the peak in medical encounters. For a marathon the peak runner flow is often in the 3.5-4.5 hour mark and for a 10 mile race may be in the 80-100 minute range. Estimating the number of volunteers needed is easier when there is race data to assist with decision making. At Twin Cities Marathon, we utilize just over 300 medical and communications volunteers for approximately 19,000 finishers of the marathon and 10 mile races (16 volunteers per 1000 finishers). The volunteers are distributed along the course at fixed medical stations, fixed first aid posts, mobile bike teams, and mobile cart teams. The largest group of volunteers is assigned in the finish area to runner triage and medical tent care teams. A tent or some form of shelter for privacy and protection from the weather will be needed for evaluating and treating runners with problems. The medical evaluation area should be located downstream from the finish line and ideally near an access site for ambulance evacuation of serious casualties. Fencing to limit access to the medical area is essential for privacy of runners who require evaluation and treatment. Except for rare circumstances, family members are not allowed in the medical treatment area to preserve privacy for other runners in the med tent “ward-like” space and to reduce the chances for inadvertent exposures to blood borne pathogens. The medical equipment and supplies are focused on the “usual” casualties for a given event. Items include cots, tables, chairs, gas heaters, fans for circulating air, tubs for ice baths, microwaves for heating blankets, ice chest for ice and water, water supply, blankets, towels, tables, chairs, drape partitions, lighting, toilet, and handwashing station. Convenience supplies like sanitary pads, tampons, contact cases, and contact solution, are helpful and can help smooth transitions out of the medical areas. The amount of supplies will vary with the conditions with more cooling supplies and equipment needed on hot days and more warming supplies for cool days. A communications system for race day that covers the course is essential to assist the medical team and respond to on course emergencies. It is helpful to have some redundancy in the plan to account for system failures. A combination of cell phones, hand held radios, and HAM radio operators allow rapid, but not always confidential communications. Text messaging, email, and web sites can be used to pass information to volunteers and competitors regarding cancelations, delays or changes. A dedicated emergency phone number distributed to all volunteers allows any race volunteer to report a medical incident and ensure rapid response. An emerging medical communication and medical record tool involves mobile phone and tablet apps that can be connected to GPS for detecting emergency incident location detection and can be used to simultaneously record the medical event in real time. When used on a mobile phone, the app can be used to connect to race command, EMS dispatch, and the participant’s emergency contact with a radio button link. These apps can also be used by participants to record their personal medical data regarding chronic health issues, medications, allergies, and usual training or pre-race weight. This information is valuable to medical responders and can speed the care of race day problems. This information traditionally has been collected on the back of the competition bib. The apps have made the data more private and easily accessible at any point on the race course. Course and Finish Line Fluids The planning for course and finish line fluids is not an exact science. There are formulas that help with the calculation and the calculations are complicated by having more than water available for fluid replacement. Water should be adequate an adequate fluid for most runners in most race situations. Here is a simple minimalist approach: one 210-300 ml cup per entrant per aid station with 120-240 ml fluid in each cup (double the number of cups for the start and finish areas). If you have a sport drink in addition to water, you will need to have both available at each water stop; a starting estimate would be 2/3 of the total water calculation for each station, although this estimate runs a risk of running out of one fluid or the other at an individual station. If the temperatures are going to be hotter than normal for the season, you may have to increase the number of cups by 50-100% as participants will often drink one or two cups of fluid and dump one on their body. An on-site potable water source (fire hydrant) will make the water volume a non-issue, leaving the cup estimate as the limiting factor (cups can be stored and used for the next event). A military style “water buffalo” is another option for transporting bulk potable water. Sports drinks can be mixed on site using bulk powdered formulations. After the finish, soup bullion can be a good initial rehydrating fluid to give the athlete an initial salt load (have a vegetarian option), in addition to water and sports drinks. Chocolate skim or 2% milk is also a good post event rehydration fluid. Documentation and Review For each race it is desirable to record the weather conditions including ambient temperature, relative humidity, sky cover (% sun), wet bulb globe temperature, black globe temperature, wind speed and direction, and WBGT (measured on site or calculated from race data) at the start and hourly through the race. This allows comparison of injury rates from year to year and event to event. Documenting each encounter is essential as each medical record becomes the legal record of the care. The records can also be used to look at the type and rate of injury associated with the race. Good records augment future planning and distribution of medical assets. After the event, at the Twin Cities Marathon we ask for a post-event report from each area leader. The general report format is “what went right, what went wrong, and what are potential solutions for the next event.” This format usually allows the medical team to gain perspective and make relevant improvements to runner safety and medical team efficiency.   Sample Medical Record from Twin Cities Marathon (This may be reproduced for your race)       References 1. Almond CS, Shin AY, Fortescue EB, et al: Hyponatremia among runners in the Boston Marathon. N Eng J Med 352:1550-1556, 2005. 2. Armstrong LE, Casa DJ, Millard-Stafford M, et al: ACSM position stand: Exertional heat illness during training and competition. Med Sci Sports Exerc 30(3):556-572, 2007. 3. Armstrong LE, Crago AE, Adams R, et al: Whole-body cooling of hyperthermic runners: Comparison of two field therapies. Am J Emerg Med 14:355-358, 1996. 4. 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