title: Effects of a New Cooling Technology on Physical Performance in US Air Force Military Personnel.
abstract: BACKGROUND
  Heat-related illness is a critical factor for military personnel operating in hyperthermic environments. Heat illness can alter cognitive and physical performance during sustained operations missions. Therefore, the primary purpose of this investigation was to determine the effects of a novel cooling shirt on core body temperature in highly trained US Air Force personnel.
  
  
  METHODS
  Twelve trained (at least 80th percentile for aerobic fitness according to the American College of Sports Medicine, at least 90% on the US Air Force fitness test), male Air Force participants (mean values: age, 25 ± 2.8 years; height, 178 ± 7.9cm; body weight 78 ± 9.6kg; maximal oxygen uptake, 57 ± 1.9mL/kg/ min; and body fat, 10% ± 0.03%) completed this study. Subjects performed a 70-minute weighted treadmill walking test and 10-minute, 22.7kg sandbag shuttle test under two conditions: (1) "loaded" (shirt with cooling inserts) and (2) "unloaded" (shirt with no cooling inserts).
  
  
  RESULTS
  Core body temperature, exercise heart rate, capillary blood lactate, and ratings of perceived exertion were recorded. Core body temperature was lower (ρ = .001) during the 70-minute treadmill walking test in the loaded condition. Peak core temperature during the 70-minute walking test was also significantly lower (ρ = .038) in the loaded condition.
  
  
  CONCLUSIONS
  This lightweight (471g), passive cooling technology offers multiple hours of sustained cooling and reduced core and peak body temperature during a 70-minute, 22.7kg weighted-vest walking test.
authors.forename: Reginald
authors.initials: R
authors.lastname: O'Hara
authors.forename: Christopher
authors.initials: C
authors.lastname: Vojta
authors.forename: Amy
authors.initials: A
authors.lastname: Henry
authors.forename: Lydia
authors.initials: L
authors.lastname: Caldwell
authors.forename: Molly
authors.initials: M
authors.lastname: Wade
authors.forename: Stacie
authors.initials: S
authors.lastname: Swanton
authors.forename: Jon K
authors.initials: JK
authors.lastname: Linderman
authors.forename: Jason
authors.initials: J
authors.lastname: Ordway
mesh_terms: D000328:Adult; D054874:Athletic Performance; D001831:Body Temperature; D001833:Body Temperature Regulation; D003080:Cold Temperature; D005080:Exercise Test; D006339:Heart Rate; D018882:Heat Stress Disorders / Q000517:prevention & control*; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D008889:Military Personnel; D011481:Protective Clothing; D013672:Technology; D013696:Temperature; D055815:Young Adult
chemical_list: D019344:Lactic Acid