Table 2.

Components of Israeli Defense Forces Heat Tolerance Testing Protocol^a

Stage	Components
Before testing	All patients with exertional heat-related injuries undergo a standard exercise heat-tolerance testing about 6 wk after the injury.
	Participants achieve complete clinical recovery (asymptomatic and normal hematologic and blood chemistry results).
	General medical examination is required.
	Participants must have a baseline rectal temperature <37.5°C.
Testing preparation	Participants avoid exercise and alcohol for ≥24 h before testing.
	Participants obtain ≥7 h of sleep the night before testing.
	Participants avoid tobacco and caffeine before testing.
	Participants drink 0.5 L of water during the hour before testing.
	Participants are encouraged to wear light clothing (shorts, no shirt for male participants1,23).
	Testing is performed during early morning hours.
	Testing is performed in a controlled environmental chamber (40°C and 40% relative humidity).
	Wind speed: none
Testing protocol	Participants walk on a treadmill for 120 min at 5 km/h (3.1 mph) with 2% incline.
	Rectal temperature and heart rate are monitored throughout testing.
	Sweat rate is calculated (difference between body weight before and after testing).
Results interpretation	Individual passes the heat tolerance testing if protocol is completed.
	Individual is deemed to have heat intolerance if rectal temperature >38.5°C (>101.3°F), heart rate >150 bpm, or no plateau is achieved (>0.45°C/h or rectal temperature-to-heart rate ratio >0.279°C/bpm).

Abbreviation: bpm, beats per minute.

^aSee Mitchell et al¹² for a more detailed history of the Israeli Defense Forces model.