The 2022 New York City Marathon was marked by unseasonably high temperatures that placed a significant strain on medical services and runners alike. The author, a physician volunteering at the event, recalls attending to a middle-aged man with heat stroke whose oral temperature measured 107 degrees Fahrenheit. Despite being at the finish line near some of the nation’s best hospitals, resource limitations such as lack of ice, inadequate cooling tubs, and insufficient vital-sign monitors compromised timely care. This experience exemplifies the growing challenge of managing heat-related illnesses in endurance sports amid climate change.
Medical teams at large-scale marathons often operate with limited resources under extreme conditions, leading to mistriage and rationing of critical equipment. The influx of heat-related cases during the NYC Marathon overcrowded medical tents, underscoring gaps in planning for extreme weather events. This scenario demonstrates that goodwill and volunteer efforts cannot substitute for systematic safety planning and adequate medical provisioning.
Several marathon events have responded to rising temperatures by implementing measures such as moving start times earlier, changing event dates, and issuing heat warnings. For example, Grandma’s Marathon in Minnesota introduced an earlier start and a half-marathon option, which correlated with reduced aid tent utilization. The International Olympic Committee established a heat risk working group before Tokyo 2020, providing epidemiologic data that continue to guide Olympic race safety. Similarly, the Los Angeles Marathon allowed runners to accept medals at an 18-mile mark to mitigate heat exposure, although the impact on health outcomes remains unclear due to limited data disclosure.
A critical limitation in improving marathon medical response lies in the fragmented and inconsistent collection of health data during events. Many races contract medical services externally without unified standards for data recording or sharing. Consequently, valuable medical outcomes, treatment details, and incident rates are often not systematically analyzed or made public, hindering evidence-based decision-making and risk assessments.
Large races capture extensive performance and demographic data but rarely integrate this information with health outcomes and environmental variables such as temperature and humidity. Establishing a shared, de-identified medical data repository across major marathons could enable predictive modeling of resource needs and optimize allocation. This approach would facilitate evaluating the effectiveness of heat mitigation strategies and inform best practices to enhance runner safety and operational efficiency.
Climate change, including intensified phenomena like the recent “super El Niño,” is increasing the likelihood of extreme heat during endurance events. Several fall marathons in the U.S. regions prone to above-average temperatures face elevated risks of heat-related illnesses. Advanced climate forecasting offers lead time, yet its integration into race preparedness remains limited, emphasizing the need for proactive, climate-informed health planning.
While runners bear responsibility for heat acclimation, pacing, and hydration, large marathons hosting tens of thousands of participants represent a significant public health concern. The scale of these events can strain local emergency systems and requires organizers to view climate risk as a shared responsibility. Implementing evidence-based strategies and improving medical infrastructure are vital to safeguarding participants’ health and preventing potentially fatal outcomes from heat illness.
In summary, marathons must evolve their medical planning to address the challenges posed by climate change. A concerted effort to collect and share comprehensive medical data, coupled with adaptive race management strategies, can enable endurance events to maintain safety amid rising temperatures. Without this shift, preventable heat-related casualties will remain an ongoing risk at mass participation races.
Vibhu Krishna, M.D., M.P.H., is a senior resident physician in the Division of Occupational, Environmental & Climate Medicine at UCSF. She is an avid runner with experience in emergency medicine, event medicine, and public health consulting.