Secondary Logo

Journal Logo

Sideline and Event Management

Review of Injury Patterns of the 2018 Bank of America Chicago Marathon to Optimize Medical Planning

Rygiel, Valerie DO1; Labrador, Hallie MD, MS2,3; Jaworski, Carrie A. MD, FACSM, FAAFP2,3; Chiampas, George DO, CAQSM, FACEP4,5

Author Information
Current Sports Medicine Reports: May 2022 - Volume 21 - Issue 5 - p 149-154
doi: 10.1249/JSR.0000000000000955
  • Free


Marathon participation continues to be an increasingly popular athletic and social endeavor for many people. The 2018 Global Marathon Statistics report states that from 2008 to 2018, there has been a participant increase of 49.43% runners worldwide (1). Marathons are no longer only for the most talented runners, rather runners of all ages and skill levels are participating. Amateur runners are entering marathons as a way to test their endurance and accomplish an admirable goal (2–4). This is evident in the fact that the average finishing time has increased from 3 to 4 h, and the average age has increased to 40 years old over the last 20 years (5,6). As the number of participants increases, however, so do the number of running related injuries (7). In runners training for a marathon, it has been reported that up to 90% will experience an injury that causes a disruption in planned training schedules. Runners who reach 30 to 45 miles of running per week are at the highest risk of injury (8–10). The increase in popularity of marathons among amateur runners creates a pressing need for a comprehensive medical plan for participants. A cross-sectional study of the 2018 Bank of America Chicago Marathon (BOACM) in 2011 focusing on hydration practices of marathon runners showed that the majority of runners seeking medical care were inexperienced and had no preexisting concern for having a medical event during the race (11). Prior studies suggest that the most common race day injuries are minor and musculoskeletal (MSK) in nature, but that all tents should be equipped to handle the rare medically catastrophic event (5,6,11–13). Running-related hyperthermia, hyponatremia, and cardiac arrest can prove fatal if there is no plan in place to manage these athletes (14). On race day, it is estimated that 25 of every 1000 runners will seek medical help and that the volume of runners seeking medical care is highest at the finish line and halfway point of the marathon (13,15–17). The finish line volume has been hypothesized to be because runners of various athletic abilities are more apt to notice aches and pain develop once they cross the finish line and the adrenaline that sustains them through the race wears off. Alternatively, the halfway point of the race is somewhat of a mental hurdle for many runners, which could prompt them to stop for care and resources to carry them the rest of the way (17). It is important to understand trends, such as these to appropriately implement a medical response plan.

The BOACM is an ideal venue to study race trends for many reasons. It is a large-scale event that draws participants from all 50 U.S. states, as well as more than 100 countries worldwide (18). The race boasts a fast and flat course that is appealing to elite runners chasing to break personal records. The world record for marathon racing has been broken in Chicago five times since inception of the race (19). As one of the six World Marathon Majors and a qualifier for the Boston Marathon, race registration in itself is competitive. Bank of America partners with more than 170 charities and thousands of runners are able to gain entry into the race by pledging to raise money for an announced cause. This allows less experienced runners to participate on race day and contributes to the diversity of running related injuries recorded. In addition, the BOACM has a long history. The 2018 race was the 51st Chicago Marathon, which has developed a well-established infrastructure over the years to track runner injury data.

This retrospective chart review of medical records from the 2018 BOACM looks at the type and volume of injury reported at various distances along the route of a large-scale marathon to determine the resources necessary at each aid station. By optimizing race day resource distribution, better medical care can be provided for competing athletes (12).


The BOACM course spans 26.2 miles and takes runners through 29 Chicago neighborhoods. Twenty-one medical stations equipped with personnel, equipment, and fast track items are distributed roughly every 1 to 2 miles along the course. In this retrospective chart review of records collected from the 2018 BOACM, which took place on October 7, 2018 (n = 1016), the diagnoses of runners seeking medical care were recorded by medical volunteers at 19 of the 21 course medical tents and the two finish line tents.

Medical Records

Two types of medical records were used: visit notes and fast track tally sheets. Visit notes were filled out when a runner stopped at a tent and was evaluated by a medical professional, while fast track tally sheets were used to quickly document runners that grabbed first aid supplies without getting a formal evaluation. Fast-track items included bandaids, vasoline, salt tabs, acetaminophen, and a topical menthol analgesic.

Excluded Data

For the purpose of this study, records from the course medical tent known as Laflin, which was located in the middle third of the race near mile marker 16, were excluded. This tent largely received transports from other nearby aid stations and data collected would therefore be duplicate. In addition, due to an error in the data collection system, there were no records available from course medical tent 17, and therefore, this tent also was excluded. Data were collected from the remaining 19 tents along the course, as well as the two finish line tents as planned. Potential subjects were identified by completion of either an electronic medical record via tablet or paper charts that were then entered into a secure electronic database by race personnel.

Study Eligibility

All registered participants with an officially recorded bib number in the 2018 BOACM were considered eligible subjects for the study. Subjects ranged in age from 18 to 75 years. Runners' consent for medical treatment was obtained via online waiver at the time of race registration. Inclusion criteria for this study include registered participants (ages 18 to 75 years) who received medical resources or evaluation at a course tent or finish line main medical tent. Participants were excluded if the documentation from the medical staff was incomplete or illegible, or if participants were younger than 18 or older than 75 years to meet criteria for international review board (IRB) exemption. This study was found to be eligible for IRB exemption by the NorthShore University HealthSystems IRB board prior to data analysis. Permission to access and analyze data was approved by the race medical director Dr. George Chiampas and facilitated by Chicago Event Management staff members Brittany Bair and Sarah Van Deusen.

Study Methods

All identifiers were removed for the purpose of this study. For runners who stopped for formal evaluations, diagnoses were categorized as either MSK, medical, wound care, or other (Table). MSK complaints were not specifically stratified by body part unless the provider annotated this in the comments section of the form and therefore was not available for analysis. The designation of “other” was largely used when a runner had a presenting concern not listed on the medical record form such as general fatigue, wanting a joint taped or braced preventatively, asymptomatic runners with diabetes checking blood sugars, or assistance with stretching. The data were divided into quartiles based on race distance: aids stations 1 to 7 (miles 0 to 10), stations 8 to 14 (miles 10 to 18), stations 15 to 20, with the exception of station 17 which was excluded as discussed above) plus station 21 referred to as the Indiana tent (miles 18 to 26), and both finish line tents (referred to as Balbo and Jackson). The type and volume of each diagnosis was then compared between quartiles using a χ2 analysis. Severity of complaints was briefly assessed by reviewing both the gross number treatment compared with those who were transferred or transported to higher level of care.

Table - Description of diagnoses categories.
MSK MSK, sprain/strain, shin splints, muscle cramping, heel pain
Medical Asthma/respiratory, chest pain, hypoglycemia, dehydration, hyperthermia, hypoglycemia, hyponatremia, syncope, dizziness, exercise-associated collapse, nausea/vomiting
Wound Care Blisters, laceration, toenail trauma
Other Other, complaints not listed on intake form (e.g., wanting a joint taped or braced preventatively, asymptomatic diabetics checking blood sugars)
Presenting complaints were divided into the subcategories of MSK, medical, wound care, and other.

The fast-track items are meant to be quickly available to runners without a formal evaluation. Items, including vaseline, bandaids, salt tabs, and the topical menthol analgesic gel, were placed in an easily accessible location outside of the medical tents and in close proximity to the race route. As runners passed the fast track station, medical volunteers recorded bib numbers and the items taken. Acetaminophen also was considered a fast track item; however, runners who were given a dose of the medication were required to come into the medical tent and speak with the tent nurse who would put a sticker on the runner’s bib to ensure that multiple doses would not be given during the race. The fast-track items were then analyzed and sorted into the same four categories: MSK, medical, wound care, or other. Fast track items designated as “other” included miscellaneous items, such as facial tissue or hand sanitizer that were not listed on the fast track recording sheets. The total number of fast-track items used over the course of the race were analyzed. For this particular metric, fast track items were not sorted by race quartiles.


Of the 63,224 registered participants, 45,515 started the race and 44,584 runners crossed the finish line. There were 1016 medical records reviewed for the purpose of this study. These records do include multiple entries for runners who stopped at more than one tent during the course of their race. Overall, 61% of all complaints were MSK, followed by 16% medical, 16% other, and 9% wound care (Fig. 1). When looking at the volume of patients along the race, there was a bimodal distribution of injured runners in the second and fourth quartiles (Fig. 2). This correlates to the halfway point of the marathon and the finish line area. Looking specifically at the ratio of each type of diagnoses in each race quartile, the percentage of medical and wound care complaints peaked in the fourth quartile (Fig. 3). A χ2 analysis of the data comparing the number of diagnoses of MSK, medical, wound care, and other complaints in each race quartile showed that there was a statistically significant difference between the types of running injury with a P value less than 0.001.

Figure 1:
Diagnoses recorded at the 2018 Bank of America Chicago Marathon.
Figure 2:
Total patients treated at the 2018 Bank of America Chicago Marathon organized by aid station.
Figure 3:
Percentage of injury type seen along the race of the 2018 Bank of America Chicago Marathon.

The MSK complaints were not specifically stratified by body part on the medical forms and so were not available for analysis. The first third of the course (aide station 1 to 7) had the fewest medical complaints and consisted of near-syncope (n = 1) and fatigue/weakness (n = 2). In the middle third of course (aide station 8 to 14), top medical conditions included asthma/respiratory (n = 5), dehydration (n = 2), and hypothermia (n = 2). The medical conditions most recorded during the final third of the course (aide station 14—Indiana tent) were syncope/exercise associated collapse (n = 4) and nausea/vomiting (n = 2). In the two finish line tents, the most common diagnosis was dehydration (n = 68); however, there were several complaints recorded of nausea/vomiting, syncope and presyncope.

Out on the course, 573 of the 593 (96.6%) runners who stopped for care were discharged back onto the course after receiving treatment. In the first third of the course, 5 of the 87 runners (5.75%) who stopped for care were transferred or transported to higher care. Comparatively, the middle third of the course escalated care for only 4 of the 333 who stopped (1.2%). The final third transferred or transported 6 of the 173 total runners (3.47%). From the two finish line tents (Balbo and Jackson), 412 of the 423 patients were discharged home (97.4%), whereas the remaining 11 patients (2.6%) were sent to the emergency room via emergency medical services.

When looking at the fast track items available for runners to quickly obtain without a formal evaluation, the MSK supplies were in the highest demand overall at 77% of the total items dispensed followed by wound care at 15%, other 6%, and medical 2%. Of the MSK supplies, topical menthol analgesic gel was the most requested (1912 samples supplied).


Large well-established races have prediction models on types of injuries, as well as of when the bell curve of runners, or highest number of patients, should be expected at any given point on the course. This helps to determine medical supply and staffing needs throughout the day of the event. Newer races can utilize these models along with their own race participant demographics to predict similar data based on average race times and the skill level of their participants (20). This study looked to provide enhanced prediction models of race day resource needs through researching injury patterns along a marathon race course. By looking at the medical records of runners along the course of the 2018 BOACM, we are better able to predict what types of medical supplies and resources are needed at each aid station.

Our Study Hypotheses

Prior to this study, we hypothesized that 1) the majority of complaints would be MSK, 2) the volume of runners seeking medical care would be highest at the finish line, and 3) as the race progressed the number of MSK injuries would increase up until a point toward the end of the race when runners would only stop for assistance if they had more serious medical symptoms. Our data supported all three of our hypotheses.

Studies exist that tally the prevalence and severity of running conditions experienced by endurance race participants as a means to gain further perspective on race day planning. For example, a 4-year cross-sectional epidemiologic study of the Baltimore marathon showed that the majority of complaints were minor with runners able to return to the course after treatment. The diagnoses were largely related to dehydration or MSK conditions (13). Of the MSK injuries during marathon racing, a compilation of epidemiologic studies showed that the knee is the most commonly affected body region with an injury frequency of 25%, followed by lower leg (20%), foot (16%), ankle (15%), upper leg (10%, hip and pelvis (7%), and lower back (7%) (6). Our data were consistent with the existing literature, as 61% of the runner complaints at the medical tents of the 2018 BOACM marathon were MSK in nature.

In regard to predicting volumes of runners requiring medical help, studies that have looked at injury patterns of other endurance races, such as the Singapore half marathon have already demonstrated that increased running distance increases the risk for running casualties (16). We saw similar results in that the largest patient volumes were at the finish line of the BOACM. However, we also predicted that the patient volume would not increase linearly along the course as runners would prioritize finishing a monumental race over more minor MSK injuries toward the end of the event (3). The same calf cramping that might have caused a patient to stop for a massage at mile 5 is more likely to be ignored at mile 25. To further illustrate this point, one can look at the data from the Indiana medical tent, which is the last of the Chicago course medical tents and is located within 0.2 miles of the finish line. Runners passing this tent have the finish within eyeshot. Typically, this tent has a very low volume of patients; however, the patients who do stop often need advanced care, such as transfer to a hospital for sudden cardiac arrest or inhalers for a severe asthma exacerbation (12,21) The data did support our hypothesis as, although the number of runners stopping to receive medical care had a bimodal distribution with peaks at the halfway point of the race and finish line, the percentage of medical complaints was highest at the finish line tents. In the 2018 race, there were only three runners who stopped at the Indiana tent; however, all of them had syncopal episodes from exercise associated collapse and required advanced care, such as evaluation with laboratories, treatment with fluids, and transfer to the main medical tent for monitoring.

Medical Tent Supplies

While each course and finish line tent should have the supplies necessary to attend to all types of possible presenting complaints, the number of each supply and personnel should differ based on projected need. For example, MSK complaints consisted of issues such as sprains/strains, muscle cramping, and shin splints. Therefore, tents that experienced particularly high volumes of MSK injuries would require more personnel capable of treating these such as massage or physical therapists. In addition, these tents should be stocked with a higher number of items for taping/bracing or topical menthol analgesic gels. Having an abundance of these items at a later course tent such as Indiana, however, would be unnecessary. The later tents will likely require provision of higher acuity care, a higher number of IV fluids, and the staff able to do these procedures such as nurses, intensivists, and paramedics for other more critical medical events.

Multidisciplinary Approach

Marathon planning should involve the cooperation of not only medical providers but logistical support from city planners and law enforcement. With a multidisciplinary approach, resources can be more efficiently allocated, thereby reducing waste or inappropriately placed items or personnel (22). The BOACM utilizes a United Command Approach to planning, which brings together the heads of all the involved major organizations such as local police and fire departments and key race organizers in order to coordinate an effective response. By linking these organizations, consensus decisions can be reached without the burden of jurisdictional boundaries. An approach like this requires ample communication not only on race day but also in the months leading up to race day (20).


A possible confounding factor that was not specifically addressed in this study is the possibility of preexisting injuries. It was not specifically analyzed how many athletes who stopped at medical tents along the course started the race already with a training related injury. The current paper medical records do have a space to record how long the injury has been present; however, this is not one of the key pieces of information that is transcribed into the electronic record. This could potentially be a focus of future research.

One potential limitation in this study is the data collection system itself. Currently the BOACM is using a combination of paper and electronic medical records. The electronic records are entered via tablet by medical volunteer scribes at some of the medical tents after paper charts have been completed. This does introduce a chance for error in transcription of the data, however, at the completion of the race the electronic records are cross checked against paper forms to ensure accuracy. In addition, fast track tally sheets are currently only available in paper form. The tablets are not yet available at all the race medical tents; however, the goal is to eventually transition to an entirely electronic data entry system (23). Race volunteer feedback has been that during large volumes of patient care, paper charts have been faster for the providers to complete.

Future Considerations

This study only looks at 1 year of the BOACM data. Longitudinal studies can be helpful to see how dependent variables such as race start time or weather can affect race injury patterns. For example, organizers of the Grandma's Marathon in Duluth, Minnesota noted a decrease in the number of runners seeking medical care after making the race start time earlier, presumably so that this summer time race could be completed before the hottest part of the day (24). Of note, the weather during the 2018 BOACM was rainy with temperatures ranging from 57°F to 61°F. These temperatures were near ideal running conditions for the endurance event, and the number of medical complaints, such as hyperthermia and electrolyte imbalances, was relatively low compared with other years. However, wet conditions could have led to an increased number of wound care complaints, such as blisters and falls. Considerations for further research should acknowledge that changes in weather would likely have an effect on results. A future longitudinal study of the injury patterns of marathons could be helpful to better understand these trends (25).


According to this epidemiological evaluation of medical records from the 2018 BOACM, the largest number of runners seeking medical care were at the finish line and halfway point of the race. The most common presenting complaints were MSK (61%), followed by medical (16%)/other (16%), and then wound care (9%). The proportion of MSK complaints increased along the course of the race from 72% to 77% to 86% of the presenting complaints in the first, middle, and last third of the race, respectively. However, in the finish line tents only 42% of the injuries were MSK. The highest percentage of medical and wound care complaints were at the finish line tents. This distribution of injury patterns can be used to more efficiently staff and supply medical resources along the course of future marathons.

Clinical Recommendations

Knowing the expected injury patterns along a marathon route can aid in reducing morbidity and mortality of participants. It is known that race distance and environmental conditions influence the incidence of medical events during endurance racing events (26). By better understanding what medical resources and personnel are needed at various distances of a marathon, health care professionals can be better equipped to handle injuries. Event planners can utilize this information to reduce waste and improve efficiency in distribution of supplies as well as personnel (12,25). Ultimately, additional longitudinal studies that enhance the strength of prediction models for injury patterns in marathon racing can serve to improve the care of runners and potentially save lives.

The authors declare no conflict of interest and do not have any financial disclosures.


1. Anderson JJ. Marathon Statistics 2019 Worldwide (Research) 2019. [cited 2021 October 31]. Available from:
2. Malchrowicz-Mośko EWA, Villarreal J, Chlebosz K, Glapa A. Motivation for running in a half-marathon among university students. Trends Sport Sci. 2018; 25:35–41.
3. Roebuck GS, Fitzgerald PB, Urquhart DM, et al. The psychology of ultra-marathon runners: a systematic review. Psychol. Sport Exerc. 2018; 37:43–58.
4. Shipway R, Jones I. The great suburban Everest: an ‘insiders’ perspective on experiences at the 2007 Flora London Marathon. J. Sport Tour. 2008; 13:61–77.
5. Jaworski CA. Medical concerns of marathons. Curr. Sports Med. Rep. 2005; 4:137–43.
6. Fields KB. Running injuries—changing trends and demographics. Curr. Sports Med. Rep. 2011; 10:299–303.
7. Miller E, Goldman J, Beck J, et al. Is marathon training safe for adolescents?Clin. J. Sport Med. 2018; 28:241.
8. Nielsen RO, Buist I, Sorensen H, et al. Training errors and running related injuries: a systematic review. Int. J. Sports Phys. Ther. 2012; 7:58–75.
9. Van Der Worp MP, Ten Haaf DS, Van Cingel R, et al. Injuries in runners; a systematic review on risk factors and sex differences. PLoS One. 2015; 10:e0114937.
10. Walter SD, Hart LE, McIntosh JM, Sutton JR. The Ontario cohort study of running-related injuries. Arch. Intern. Med. 1989; 149:2561–4.
11. Brown S, Chiampas G, Jaworski C, Passe D. Lack of awareness of fluid needs among participants at a midwest marathon. Sports Health. 2011; 3:451–4.
12. Chan JL, Constantinou V, Fokas J, et al. An overview of Chicago (Illinois USA) marathon prehospital care demographics, patient care operations, and injury patterns. Prehosp. Disaster Med. 2019; 34:308–16.
13. Tang N, Kraus CK, Brill JD, et al. Hospital-based event medical support for the Baltimore Marathon, 2002–2005. Prehosp. Emerg. Care. 2008; 12:320–6.
14. Fatima Y, Ahmed A, Abdullah S, Shareef I. Epidemiology of illnesses encountered during a marathon race—an EMS perspective. Int. J. Emerg. Med. 2015; 8:3.
15. Fredericson M, Misra AK. Epidemiology and aetiology of running related injuries. Sports Med. 2007; 37(4–5):437–9.
16. Tan CM, Tan IW, Kok WL, et al. Medical planning for mass-participation running events: a 3-year review of a half-marathon in Singapore. BMC Public Health. 2014; 14:1109.
17. Nguyen RB, Milsten AM, Cushman JT. Injury patterns and levels of care at a marathon. Prehosp. Disaster Med. 2008; 23:519–25.
18. Bank of America Chicago Marathon Web site [Internet]. Chicago, IL: Bank of America Chicago Marathon; [cited 2021 Mar 1]. Available from:
19. Guinness Book of World Records Web site [Internet]. Guinness Book of World Records Worlds Best Progressions: Road Race. ARRS. [cited 2021 Mar 20]. Available from:
20. Chiampas G, Jaworski CA. Preparing for the surge: perspectives on marathon medical preparedness. Curr. Sports Med. Reports. 2009; 8:131–5.
21. Noble BJ, Maresh CM, Allison TG, Drash A. Cardio-respiratory and perceptual recovery from a marathon run. Med. Sci. Sports Exerc. 1979; 11:239–43.
22. Ewert GD. Marathon race medical administration. Sports Med. 2007; 37(4–5):428–30.
23. Hanken T, Young S, Smilowitz K, et al. Developing a data visualization system for the Bank of America Chicago Marathon (Chicago, Illinois USA). Prehosp. Disaster Med. 2016; 31:572–7.
24. Crouse B, Beattie K. Marathon medical services: strategies to reduce runner morbidity. Med. Sci. Sports Exerc. 1996; 28:1093–6.
25. Bistaraki A, Georgiadis K, Pyrros DG. Organizing Health Care Services for the 2017 “Athens Marathon, The Authentic:” Perspectives on Collaboration among Health and Safety Personnel in the Marathon Command Center. Prehosp Disaster Med. 2019; 34:467–72.
26. Breslow RG, Giberson-Chen CC, Roberts WO. Burden of injury and illness in the road race medical tent: a narrative review. Clin. J. Sport Med. 2020; 31:e499–505.
Copyright © 2022 by the American College of Sports Medicine