International Journal of Biometeorology

, Volume 61, Issue 8, pp 1471–1480 | Cite as

American football and fatal exertional heat stroke: a case study of Korey Stringer

  • Andrew GrundsteinEmail author
  • John A. Knox
  • Jennifer Vanos
  • Earl R. Cooper
  • Douglas J. Casa
Original Paper


On August 1, 2001, Korey Stringer, a Pro Bowl offensive tackle for the Minnesota Vikings, became the first and to date the only professional American football player to die from exertional heat stroke (EHS). The death helped raise awareness of the dangers of exertional heat illnesses in athletes and prompted the development of heat safety policies at the professional, collegiate, and interscholastic levels. Despite the public awareness of this death, no published study has examined in detail the circumstances surrounding Stringer’s fatal EHS. Using the well-documented details of the case, our study shows that Stringer’s fatal EHS was the result of a combination of physiological limitations, organizational and treatment failings, and extreme environmental conditions. The COMfort FormulA (COMFA) energy budget model was used to assess the relative importance of several extrinsic factors on Stringer’s EHS, including weather conditions, clothing insulation, and activity levels. We found that Stringer’s high-intensity training in relation to the oppressive environmental conditions was the most prominent factor in producing dangerous, uncompensable heat stress conditions and that the full football uniform played a smaller role in influencing Stringer’s energy budget. The extreme energy budget levels that led to the fatal EHS would have been avoided according to our modeling through a combination of reduced intensity and lower clothing insulation. Finally, a long delay in providing medical treatment made the EHS fatal. These results highlight the importance of modern heat safety guidelines that provide controls on extrinsic factors, such as the adjustment of duration and intensity of training along with protective equipment modifications based on environmental conditions and the presence of an emergency action plan focused on rapid recognition and immediate on-site aggressive cooling of EHS cases.


Heat illness Athletics Safety policy Wet bulb globe temperature Energy budget modeling 


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Copyright information

© ISB 2017

Authors and Affiliations

  • Andrew Grundstein
    • 1
    Email author
  • John A. Knox
    • 1
  • Jennifer Vanos
    • 2
    • 3
  • Earl R. Cooper
    • 4
  • Douglas J. Casa
    • 5
  1. 1.Department of GeographyUniversity of GeorgiaAthensUSA
  2. 2.Scripps Institution of OceanographyUniversity of California at San DiegoLa JollaUSA
  3. 3.School of MedicineUniversity of California at San DiegoLa JollaUSA
  4. 4.Department of KinesiologyUniversity of GeorgiaAthensUSA
  5. 5.Department of Kinesiology, Korey Stringer InstituteUniversity of ConnecticutStorrsUSA

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