In the summer of 2016, a concurrent full iron-distance and 70.3 (half iron-distance) triathlon took place in British Columbia, in a rural community in the coastal mountains. Full iron-distance triathlons are endurance events consisting of sequential swim (3.86 km per 2.4 m), cycle (180.24 km per 112 m), and running segments (42.2 km per 26.22 m). Iron-distance triathlons have their roots in an initial event at Waikiki beach on O’ahu, Hawaii in 1978, though the first modern triathlon was recorded in San Diego in 1974 (18,22,23,44). The event moved to Kailua-Kona in 1981 and continues to this day (27).
The sport has rapidly grown in popularity. USA Triathlon reported 134,942 annual members and an additional 342,189 1-d memberships in 2010 (34). In 2015, there were approximately 4.24 million participants in triathlons in the U.S., up from 3.61 million the previous year (40). There are currently 40 Ironman races worldwide, with a variety of distances, contrasting climates, and terrains (19,20,33).
Given the popularity of triathlons and the potential serious illnesses and injuries that may arise in the course of competing in a triathlon (1,2,6,10,13,17,30,32,42,45,48), more outcome studies are needed to grow the evidence base (11,16). Although there is a wealth of literature regarding triathlon training injuries, there is a relative dearth of high-quality, prospective studies presenting composite data from triathlons across a total event (11). This type of composite data is essential to health systems planners when anticipating the potential community impact on baseline resources and when attempting to create risk-matched onsite support and event medical and health services.
It is hoped that building the evidence base will support efforts to prevent illnesses and injuries from occurring and support clinicians to “right-size” an onsite emergency medical response for this event type. In the following article, we seek to extend and develop the literature and evidence base by reporting on the event, health assets, and patient demographics for a 2016 event. This study further extends and develops the literature based on event medicine in the sport of triathlons.
The study gathered data from a single full and half triathlon held in a rural community on the west coast of British Columbia, in the summer of 2016.
Prospective Observational Study
Data on event characteristics, patient presentation rates, percentage of patients transferred by ambulance, transfer to hospital rates (TTHR), ambulance transfer rates (ATR), and medical usage rates were collected.
Study participants were consecutive athletes in the event who presented to the field clinic for treatment of illnesses or injuries on the day of the triathlon. Dispatch information for on-course medical calls also is presented.
Event data included the number of athletes registered, the number of athletes who competed at each distance, and data related to the climate and weather throughout the competition. Patient data consisted of predetermined demographic, diagnostic, treatment, and outcome data based on an ongoing MGM Event and Patient Online Registry (28).
Event data were gathered via event medical organizers, clinicians and registry study personnel. Meteorological data (e.g., weather conditions, sky coverage, humidity, and temperature range) were extracted from Environment Canada (12). Patient data were collected through preprinted patient encounter forms (PEF).
The authors worked with a team of five medical students who acted as research assistants. On the day of the event, an orientation was provided for both the research team and the clinical team including an explanation of the purpose of the study, a description of the event, and a review of the documentation forms for patient encounters. The PEF were distributed to static medical care sites on-course, at Finish, and with mobile response teams. PEF were completed and collected for each consecutive patient who presented for assessment and treatment by members of the event medical team.
Research assistants circulated for the duration of the event, providing support to clinical staff to ensure all of the fields on the PEF were completed. In the case of incomplete fields, missing fields were highlighted, and clinicians were requested to complete the missing fields in real time. During the event, data from all PEF were entered into an Excel spreadsheet by research assistants (C.B., K.S., H.S., C.V., A.Y.).
Data were checked for accuracy against the original records by one of the lead researchers (S.T.). Data were analyzed using descriptive statistics.
Ethical approval for this project was granted from the University of British Columbia and the Justice Institute of British Columbia Research Ethics Boards.
The event was held in a small community on the west coast of British Columbia with a population of approximately 10,000 permanent residents and a large influx of tourists in the winter and summer seasons (41,43). The community has access to high-quality, comprehensive medical resources, centralized within an urgent care center. The urgent care center had a 16-bed emergency clinic open from 8:00 am until 10:00 pm daily with laboratory and diagnostic imaging capabilities (x-ray and computed tomography [CT]). There were no inpatient beds. The center also had a helicopter pad used by the local resort and the ambulance service for patient transports. With the nearest community hospital 1 h away on a paved road (60 km per 37 miles), and the nearest tertiary care center 2 h away (120 km per 74 miles), the urgent care center had to balance the needs of local residents along with the needs of the surge population related to the triathlon (participants, coaches, family, friends, supporters, volunteers, staff, vendors, etc.). Baseline ambulance services in the community normally included one active and one on-call ambulance per shift. The same level of coverage is standard in an adjacent community through which the bike course travelled.
Climate and weather
The temperature at the start of the race was recorded as 9.2°C (48°F), with a maximum temperature of 27.3°C (81.1°F) recorded at 3:00 pm (12). Of note, the relative humidity index was in the high 90s until 8:00 am when the humidity index fell steadily into the low teens.
Number of athletes
A total of 1404 individuals participated in the Full Ironman-distance triathlon and an additional 519 athletes took part in the Half/70.3. Table 1 provides details of the participant demographics for both races.
Unique event features
From an athlete’s perspective, a unique challenge for this iteration of the triathlon included the cycling portion of the event. The course had substantial elevation changes, the winds are usually high, and riders were unsheltered from the cross breeze (Personal Communication, Mr. Jordan Myers, multiple triathlete, November 26, 2016). From a medical services perspective, the running portion of the event included substantial intervals in paved trails, where direct vehicle access was not possible.
Size, composition, and deployment of medical team
There were 120 members of the onsite medical team, which included 56 first responders (paramedics, fire fighters, occupational first aid attendants, lifeguards), 16 medical students, 3 allied health professionals (pharmacist, physiotherapist, respiratory therapist), 11 registered nurses, 4 resident physicians, 5 attending physicians (four emergency department (ED) physicians and one OB/GYNE), and 24 nonclinical operations support personnel (Table 2). Additional ambulance support included the following resources: six ambulances with rolling deployments (split into two shifts — day and night), one incident commander, one site communications officer, one tactical dispatcher, and one logistics officer.
Deployment of medical assets
The course was active for approximately 18 h (~6:00 am to midnight). Medical assets were deployed in the morning and then redeployed as athletes completed each leg of the course. The course coverage was organized into four functional zones with overlapping zone coverage and key operational periods for medical planners (Figure).
- The Swim Zone, arguably the most dangerous portion of a triathlon, required on-water boat, paddleboard, and lifeguard support, as well as shore-side nonurgent and urgent medical care. A specialized team provided the on-water coverage. The contracted medical team described in this report provided shore-side support for the swim portion of the event and transition 1 (T1), where swimmers changed from wet suits into their bike attire and mounted their bikes. Note that when the last swimmer was out of the water, the Bike Zone was already well underway, requiring overlapping zone coverage.
- The Bike Zone required mobile trauma and medical response to cover substantial distances. Connected by robust communication and dispatch systems, water and aid stations, course marshals, motorcycle medics, nonemergency transport vehicles, sweep vans, and additional contracted ambulance support were deployed along this section of the course. Medical coverage for the Bike Zone began with the first Half-Ironman/70.3 competitor completing the swim and entering T1 and closed when the last competitor in the Full-Ironman dismounted their bike at T2 and began the run.
- The Run Zone included both transition 2 (T2) and the marathon/half-marathon leg of the event. T2 marked the end of the bike portion, and the beginning of the final, running leg of the event. The marathon began when the first cyclist dismounted, and finished when the last participant crossed the finish line, usually around midnight. Because this triathlon was a concurrent half and full distance, the open hours of the Run Zone necessitated almost 15 h of course coverage. This duration was notable when compared with the usual operating hours (approximately 6 h) for a standalone marathon. Medical coverage of the Bike and Run portions of the event overlapped by many hours, with the first overall event finisher completing the event before the last cyclist dismounted.
The Finish Area included the finishing chute as well as the main medical tent and all of the support services, vendors, sponsors, food, stages, spectators, and other elements of the event's finish pavilion. The main medical clinic (a 40 × 80 tent at the finish line) was staffed from 5:00 am until 1:00 am the next morning (1 h after the closing of the course). The medical tent was a veritable field hospital, equipped to deal with everything from first aid to advanced resuscitation. The few patients who needed additional investigation and treatment in a hospital setting benefited from the advanced coordination and planning between the on-event medical team, the ambulance service, and the local ED.
Mobile medical deployment
Given historically low rates of utilization for static first aid stations on the Bike and Run Zones (2012–2015 event coverage), emphasis was allocated to providing mobile medical assets capable of responding to water stations and scene calls. Accordingly, to support injured and/or exhausted athletes during the bike and run portions of the race, we deployed the following resources:
- □ Roving motorcycle team (n = 8) in Bike Zone
- □ Ambulances (n = 6) in Bike and Run Zones
- □ Nonemergency transport vehicles (NETV) (n = 5 vans)
- □ Gator on key Run Zone trail section (n = 1)
- □ Bicycle teams in Run Zone (n = 2)
Mobile assets were dynamically redeployed through the day to account for the spread of the athletes as zones of the course opened and closed. Automatic external defibrillators were accessible throughout with mobile response teams.
Communication and logistics
Medical dispatch logged 182 separate communications. Thirty-three of those calls required a mobile resource to proceed to the scene of an incident. All were nonemergent cases at call out. There was a single call for ambulance transport.
Over the course of the day, there were a total of 181 patient encounters in the field clinic with 179 unique individuals. Within the study group, there were two “revisits” — individuals who presented for care in the field clinic on two occasions during the event. Forty-three female patients (42 unique; 23%) and 139 male patients (138 unique; 77%) presented, which was consistent with the demographic of the race participants overall. There were an additional 34 encounters for dispensary level services, such as blister care and over-the-counter medication requests (i.e., acetaminophen, calcium carbonate antacid, diphenhydramine, ibuprofen, loratadine, ibuprofen, loperamide).
The average age of those seen in the field clinic was 41 years (range, 21–69 years); age data were missing for three patient encounters. The majority of patient interactions were with athletes (n = 179/181; 99%); the other two encounters were with staff/volunteers.
The race noncompletion rate for patients seen by the medical team was 16% (29/179) because the majority of patients finished their races. Of those who did not finish, patients came off of the course during the swim (3/29; 10.3%), the cycle (14/29; 48.3%), and the run (12/29; 41.4%). Data were missing for 12 (6.7%) of 179 encounters. The average length of stay in the field clinic was 44 min (range, 1–170 min) with time data missing for 6 (3.3%) of 181 encounters.
Roughly three fourths of patients seen in the field clinic provided information regarding triathlon experience (73.2%). The average number of completed triathlons was 5.56 (range, 0–70). Five patients reported this to be their first triathlon.
Patient Presentations and Transfer Rates
Gastrointestinal issues were the most common clinical presentation (50/181, 27.6%), followed by musculoskeletal injury (46/181; 25.4%), and nonspecific dizziness (37/181, 20.4%). Exhaustion/exposure was not uncommon (20/181, 11.1%), and for 21 of 181 encounters, the chief complaint fell outside of the above categories. Three patients treated were found to be hyponatremic (defined as a sodium level less than 135 mmol·L−1; measured using an iStat™) with serum sodium levels of 125, 124, 125 mmol·L−1, respectively). Each individual was treated with hypertonic saline and had resolution of symptoms. None had a seizure, and all three were uneventfully discharged tolerating oral fluids.
Patient presentation rates and TTHR from the patient data are presented in Table 3. Of note, three patients were referred off-site for assessment at the local urgent care center. One patient was transferred by ambulance (male, 54, syncope), and the other two were transferred via the NETV — (i) female, 66, syncope, and (ii) female, age unknown, complex wound care.
Local urgent care center
The local health center saw a total of six patients not referred by the event medical team that were directly associated with the triathlon during the 72 h surrounding the event (1 d before, day of, and 1 d after). This was determined through prospective triage questions as part of a quality assurance initiative. These self-presenting patients included: two athletes seen prerace (foot injury; other), one volunteer and one spectator were seen on the day of the event (laceration, ×2), and two athletes were seen on the day after (foot injury; rash).
Onsite medical teams are typically embedded in triathlons because there are rare, serious health challenges associated with triathlon competitions such as fatalities (14–17,26,45), hyponatremia (9,26,35), significant thermal issues (7,16), water-related illness/fatalities (1,6,10,30,35,38,48), and other severe illnesses/injuries (2,32,42). Less serious clinical presentations such as exercise associated collapse (4), MSK injuries (3,5,8,11,15,18,34,36,39,46,47), GI illness (31), and other health challenges are also documented (5,8,11,27,29,34,37) and must be considered in the planning phase.
Accordingly, supporting the competing athletes required the creation of an onsite, multidisciplinary, advanced life support, health care team deployed along the entire course with the goal of reducing fatalities, supporting athletes to continue when possible, or transport when not possible, preserving baseline services and minimizing the impact on local health infrastructure. Despite the risk of potentially life threatening health challenges, there is scant research into injuries and illnesses sustained by triathletes during competition, or composite data on participant presentations to assist in emergency medical and health services planning.
There were few ambulance transports in the present study. The rapid deployment of coordinated mobile resources obviated the need for ambulance response to every scene call, and most incidents were resolvable without an ambulance transport. Collaboration between event and ambulance communications team members permitted coordinated responses to incidents on course. It was fortunate that there were no major traumas on the Bike Zone in this year. Note that this result should not be interpreted as sufficient evidence to reduce the capacity to respond to a traumatic incident over the large distances of the Bike and Run Zones.
The level of service provided by the contracted on-event teams and the expanded ambulance coverage minimized impact on local community infrastructure. Additional factors may have included benign weather in contrast to other triathlons (e.g., 7, 16) and the relatively experienced competitors. This was the fourth year this event was held in this location. Anecdotally, there were more patient encounters in previous years.
Patient presentation rates vary widely in published triathlon case reports. Bertola et al. (5) studied 153 triathletes in Brazil who completed short (77%) and Olympic (23%) distances. Two participants reported injuries arising from participation in the race (equivalent to a patient presentation rate [PPR] of 13 per 1000). Furthermore, injuries that occur during competitions are reported to occur at approximately one sixth the rate of injuries during training (5,11).
Gosling and colleagues (15) reported on two Australian triathlons involving a total of 3884 athletes. Across the two events, there were 91 patient presentations, translating to a PPR of 23 per 100. In a later published study, Gosling and colleagues (14) reported on a case series of Australian triathlons that included Sprint/Olympic (62.2% of participants) and Fun distances (37.8% of participants) with a focus on understanding medical presentations during the events. The series included 10,197 registered participants of which 225 presented for medical care. Based on their report, across the series, there was PPR of 22 per 1000 participants across all race distances. Injuries were sustained during the running and cycling portions of the events (38.4% and 14.3%, respectively). Lower limb injuries (59.5%) and dermatological injuries (28.6%) were the most common presenting complaints. Both studies exhibit a stable PPR.
Conversely, Rimmer and Coniglione (34) studied 575 nonelite triathletes in Oklahoma who participated in concurrent half and full triathlons, as well as half and full Aquabike races. One hundred and four individuals sought medical care. This represents a PPR of 181 per 1000 athletes.
In the present study, the PPR was 94 per 1000, which positions our reported illness/injury rates in the mid range. However, this result should be interpreted with some caution given the mix of distances in each report, the variable composition of the races (i.e., Aquabike races do not include a run), the variable climates for each of the races, and potential differences in the training and experience levels of the participants in each of the studies.
Of interest to triathletes, sports medicine physicians, and athletic trainers might be the correlation (if any) between triathlon experience and illness/injury rates. In the present study, athletes were relatively experienced with an average of 5.5 triathlons completed. This statistic may be unique to this study.
As illustrated above, the published literature on triathlon case reports (and a two-case series) contain highly variable findings with regard to the PPR, pointing to the need for additional research to clarify and understand why there are such varying reports regarding illnesses and injuries during triathlons. Several researchers are investigating possible explanations for differing performance outcomes (21–25). In addition, the discussion points to a need to standardize the statistics reported to permit comparisons between similar events. More precise predictions of patient presentations and transfer rates will assist event medical planners in “right-sizing” their deployments to their events.
Limitations and Future Directions
The main limitations of the results presented in this article include:
- a single year of data,
- some incomplete data (discussed above), and
- a lack of robust data about the number of patient encounters associated with each race (i.e., the full and half versions).
In future years, our data collection will incorporate additional dispatch data; more knowledge about the nature of the calls on the course will be useful for medical planning. As well, we are interested in investigating the degree of correlation between the number of races completed and illness/injury rates. This would require that we collect data on the number of races completed by all race participants, whether or not they presented for treatment, and the results of that study may support changes to education and training for future triathletes.
Mass participation events involve thousands of simultaneous participants and spectators and pose an increased risk of injury and illness compared to similar populations in noncrowd/noncompetition conditions. This may strain baseline community health resources. The incorporation of a coordinated event medical plan and team, with integrated on-course and at-finish coverage, may minimize impact on the baseline ambulance services and the health infrastructure of the host community. This article contributes a detailed description of the event, logistical challenges, onsite medical services, and patient presentations, providing data that will permit event medical directors and event planners to “right-size” the medical response for these and similar events. It is necessary to continue to build the science underpinning mass gathering health and mass participation events.
This project was unfunded and overseen by the UBC Mass Gathering Medicine Interest Group under the Event and Patient Registry Project (http://www.ubcmgm.ca/registry).
The authors wish to thank Mr. Jordan Myers and Mr. Kevin Jones of Odyssey Medical for their support of this project. In addition, Dr. Greg Anderson and the excellent research assistants (Chris Bitcon, Kelly Soros, Holly Sherman, Christian Vadeanu, Ashley Yip) made valuable contributions to this study. Ms. Cindy Sellers was our liaison with local health authority services, and Mr. Daniel Doan, Special Operations, BC Emergency Health Services, provided valuable information regarding baseline and augmented ambulance support for the event.
Conflict of Interest Statements: S.T. is part of the leadership team for Odyssey Medical, a company that supplies medical services for events. She was part of the planning team, but not part of the onsite medical team for this event in 2016. She has worked clinically at this event in prior years.
A.L. is part of the leadership team for Odyssey Medical, a company that supplies medical services for events. He was part of the planning team, but not part of the onsite medical team for this event in 2016. He has worked clinically at this event in prior years.
R.B. has no conflict of interest with regard to this project.
M.C. is a member of the Odyssey Medical team that provided on site medical services for the triathlon. He was on site as a nurse for part of the day and received a small honorarium.
T.G. is a consultant member of Odyssey Medical, and was the Event Medical Director for this triathlon, for which he received a small honorarium.
T.G., A.L., and S.T. were responsible for the research conception and design. T.G., R.B., M.C., and C.S. were involved in the implementation of this research project. S.T. undertook the analysis of data and the draft article. All authors contributed to the interpretation of the research findings. A.L. and S.T. developed the initial publication outline. S.T., R.B., and M.C. wrote the first draft article. S.T. and A.L. completed all subsequent drafts of the manuscript. All authors reviewed the made critical revisions for important intellectual content and approved the final article.
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