Jan 29, 2015
Ahead of the Pack

Making sure your athletes don’t succumb to heat illness means knowing the latest research on the topic. This year, we turned to the Korey Stringer Institute for insight.

By Lesley Willis & Dr. Douglas Casa

Lesley Willis, ATC, is the Vice President of Information for the Korey Stringer Institute (KSI) and a master’s student in the Department of Kinesiology at the University of Connecticut. She can be reached at: [email protected]. Douglas Casa, PhD, ATC, FACSM, FNATA, is the Chief Operating Officer of the KSI and a member of its Medical and Science Advisory Board. He is also the Director of Athletic Training Education and a Professor in the Department of Kinesiology at UConn. He can be reached at: [email protected].

Don’t forget to stir the water.” This phrase is often heard in medical tents at endurance events across the country. Stirring the water is an essential part of using cold-water immersion to treat an athlete experiencing heat stroke, but the act is easily forgotten in the hustle and bustle of the tent. By stirring the water around a hyperthermic athlete, their body is not able to form a pocket of heat and more rapid cooling can ensue.

Here at the Korey Stringer Institute (KSI) at the University of Connecticut, “stirring the water” has a second meaning. We are also aiming to stir the water when it comes to examining current policies and procedures for preventing sudden athlete death. We feel it’s important to shake up the old system and continually explore new ways we can keep our athletes safe and healthy.

Recently, KSI researchers performed a national review of high school state association guidelines for guarding against heat illness during the fall sports preseason. When comparing them to the procedures preferred by the KSI, what we found was staggering. Only one state (New Jersey) met our ideal guidelines–in fact, three states had none at all.

At the college level, athletic departments should be reviewing and tweaking their heat illness guidelines and emergency action plans on an annual basis. Because college athletes are often exercising at a higher intensity than high school athletes, they are at greater risk for heat illness. We’d like to send a wakeup call to athletic trainers and medical personnel at every level that it’s time to stir the water.


When the KSI conducted its review of state association guidelines, researchers used the NATA consensus statement, Preseason Heat Acclimatization Guidelines for Secondary School Athletics, as a measuring stick. The statement defines parameters for a safe practice session, recovery period, heat acclimatization period, and walk-through practices. It also provides a 14-day acclimatization guide to a safe preseason. The guidelines are easy to follow, effective, and inexpensive–and every state should be able to easily adopt them.

When consulting with an athletic organization or college athletic department on its current guidelines or helping one to create a policy, the KSI also uses the NATA consensus statement. The KSI has helped over 20 national and international organizations revise their protocols and enhance the dissemination of accurate information regarding the prevention of sudden death in sport. These organizations include USA Cycling, Safe Kids USA, the NCAA, Boston Athletic Association (which puts on the Boston Marathon), United States Tennis Association, NSCA, American College of Sports Medicine, International Tennis Federation, NFL Players Association, and many others. We have also helped the U.S. Army revise its return to duty guidelines following exertional heat stroke.

Just last year, the KSI assisted the University of Nevada sports medicine staff in creating heat illness safety guidelines for all of its sports programs. Nevada’s guidelines provide a definition and description of each heat illness, and diagnostic criterion, intrinsic and extrinsic risk factors, and treatment guidelines for each illness. It discusses prevention strategies, such as what should be included in a preseason physical examination, proper heat acclimatization guidelines, daily pre-practice, practice, and post-practice precautions, and return-to-activity guidelines.

In addition to the above, Nevada’s policy calls for one more very important thing: education of the medical team (including emergency medical services), coaches, and the student-athletes themselves. This includes implementing educational and refresher sessions, and continual practice and preparation exercises to train personnel for heat illness emergencies.

Education is an important part of any set of guidelines because coaches are largely under-trained in regard to heat illnesses. This is something the KSI is taking major steps to change. Without the proper medical staff on site, which is the case at many high schools, coaches are in charge when emergencies occur. A coach is not an adequate stand-in for an athletic trainer by any means, but it is still important that they be educated about heat illness conditions in order to handle dangerous situations properly.

In a lot of cases, the current situation is a dangerous one. That’s why the KSI advocates for the creation of complete, comprehensive guidelines for every state, college, and athlete organization. Having written guidelines isn’t a guarantee that death won’t occur, but when a policy is in place and coaches, athletes, and medical personnel are educated about it, athletes have a better chance at survival should a problem arise.


In the KSI’s opinion, the two gold standard methods for preventing exertional heat stroke death are cold water immersion and rectal temperature monitoring. This isn’t to say that other precautions like staying hydrated and wearing breathable clothing or having fans on the sideline to stay cool aren’t important. In fact, staying hydrated is the first step to avoid having to resort to these two methods. Let’s take a closer look at why cold water immersion and rectal temperature monitoring are considered the best and how you can employ them in your setting.

Anecdotal evidence that cold water immersion is the most effective treatment for exertional heat stroke has been around for decades, but scientific evidence was finally documented in a 2009 study. Using a systematic review, researchers examined all existing literature on whole body cooling in the treatment of exertional hyperthermia and found that ice water immersion at two degrees Celsius was the most effective method of treatment. The practice decreases core temperature by 0.35 degrees Celsius per minute.

The latest NATA Board of Certification educational competencies include the cold water immersion method, and for good reason: Heat stroke has been 100-percent survivable if recognized immediately and aggressive whole body cooling via cold water immersion takes place on site. In addition to being so effective, it’s also simple, safe, and budget-friendly.

The cold water immersion process, including set-up, can be summed up in 12 steps:

1. Fill a tub halfway with water, under a tent or somewhere shaded 2. Have more water and four to five full-size coolers of ice nearby and ready to add to the tub 3. Keep the water cooler than 60 degrees Fahrenheit (the cooler the better) 4. If an athlete presents with signs of exertional heat stroke, take his or her vital signs 5. Determine central nervous system function 6. Submerge the athlete into the tub as far as possible 7. Support the athlete by holding them upright under their armpits with a towel or sheet 8. Place iced towels on their head and neck 9. Alert your local emergency medical services 10. Stir the water vigorously 11. Continuously monitor vital signs and central nervous system function 12. Continue cooling the athlete until a rectal thermometer reading registers 102 degrees Fahrenheit or lower.

There are not any official published specifications for the size of an immersion tub, but we recommend using at least a 150-gallon tub (which should hold most large football players). Tubs can be bought from medical company suppliers, or you can use something like a Rubbermaid stock tank. As long as an athlete can be submerged in the water to at least their chest, you’ll be in good shape.

The second gold standard of treatment for heat illness may not be a topic everyone is comfortable discussing, but it’s an important one. The latest research tells us that a rectal temperature reading is the most accurate way to measure core temperature.

Two recently published articles examined the effectiveness of several commonly used methods for core temperature reading. Rectal temperature emerged as the most accurate method, followed closely by ingestible thermistors, which measure gastrointestinal temperature. Ingestible thermistors have great value in many circumstances, but the downside in athletics is that they must be ingested at least five hours prior to taking a temperature reading.

Temporal, oral, aural, and axillarly thermometers were found to be extremely inaccurate and unreliable for exercising individuals. These methods registered temperatures at least half a degree lower than the rectal thermometer readings, putting them below the cutoff for validity.

In the past, rectal thermometers were considered too invasive and not worth the hassle. Today, a lot of athletic trainers know they should use a rectal thermometer, but opt for less reliable options due to comfort and familiarity. The real question we need to ask ourselves is, “Is an athlete’s comfort level and privacy concerns worth sacrificing their life?” Would an athletic trainer neglect to use an AED on a female athlete because her shirt must be removed? Never.

The NATA Board of Certification has recognized the accuracy of rectal temperature readings, and recently made changes to its educational competencies to reflect this. Beginning in the 2012-13 school year, all accredited athletic training education programs will be required to teach their students how to use a rectal thermometer and explain why it is both necessary and important.

Using a rectal thermometer is safe and simple, which is why its use is highly recommended by the NATA. It can be boiled down into nine simple steps. If possible, do the following in an area removed from the playing field, like under a tent on the sideline or in the athletic training room:

1. Drape the patient appropriately for privacy 2. Position the patient on their side with their top knee and hip flexed forward 3. Make sure the probe is cleaned with isopropyl alcohol 4. Lubricate the probe 5. Make sure the probe is plugged into the thermometer 6. Turn the thermometer on 7. Insert the probe 10 centimeters past the anal sphincter 8. If you meet resistance while inserting, stop and remove the probe, then try again 9. Leave the probe in for the duration of treatment.

A core temperature of 104.5 degrees Fahrenheit indicates that the athlete should be cooled immediately. Without a fast temperature reading, cooling is delayed and the amount of time above the critical threshold increases. We know from current research that the main factor for survival of heat stroke is the amount of time spent above this critical threshold, so quickly and accurately obtaining a core temperature reading is paramount to effective treatment.

When purchasing a rectal thermometer, look for one that is flexible (often called a thermistor) with a long enough probe so that when immersing an athlete, the probe can remain in while the thermometer stays dry. Also be sure that it has a high enough temperature range, up to at least 112 degrees Fahrenheit.

It’s easy to see why cold water immersion and rectal temperature monitoring are gold standards of treatment. They can also be very easily implemented on the field. All they require is a little planning and preparation by the athletic trainer. Coupled together, any athletic program that uses them will be in the right position to handle an emergency exertional heat stroke situation.

To access the NATA’s Preseason Heat Acclimatization Guidelines for Secondary School Athletics, go to: www.nata.org/health-issues/heat-acclimatization.

For a downloadable copy of Nevada’s heat illness guidelines, go to the KSI’s Web site at: ksi.uconn.edu/resources/resources.html.

To view full references for this article, go to: www.Training-Conditioning.com/references.


The Korey Stringer Institute (KSI) was formed soon after Stringer, a Minnesota Vikings offensive lineman, died from exertional heat stroke during a preseason practice in 2001. Stringer’s wife Kelci founded the Institute along with his agent James Gould and the help of Douglas Casa, PhD, ATC, FACSM, FNATA, Director of Athletic Training Education and a Professor in the Department of Kinesiology at the University of Connecticut.

The KSI aims to help keep athletes safe from sudden death, especially as it relates to exertional heat stroke. Kelci Stringer spoke at UConn’s commencement in May, where she further explained the goals of the KSI.

“The Institute’s mission is both personal and absolute,” she said. “It is to provide first rate information, resources, assistance, and advocacy for the prevention of sudden death in sport, especially as it relates to exertional heat stroke–which ironically, has had a 100-percent survival rate when immediate cooling is initiated within 10 minutes of collapse.

“Currently, exertional heat stroke is among the top three reasons athletes die while playing sports,” she continued. “The goal of the Korey Stringer Institute is to raise awareness by teaching professionals and athletes how to avoid the conditions that lead to heat stroke and other heat related illnesses, treat heat related illnesses when they occur, and ultimately prevent all heat related deaths.”

The KSI has partnered with the NFL and Gatorade to provide educational services like distance learning workshops and on-site educational talks. A large part of the KSI’s work involves helping schools and organizations examine and critique their current heat illness prevention policies, then working with them to revamp the protocols to make them as safe and effective as possible.

Because the KSI is in the constant process of keeping up with newly published research and reports related to heat illness and prevention tactics, we want to make sure our Web site can be a resource for the public in this way. We will soon begin publishing an article of the day on the site with an intent to keep the public educated and updated.

To learn more about the KSI, visit: ksi.uconn.edu.

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