title: Cooling the neck region during exercise in the heat.
abstract: BACKGROUND
  Cooling the neck region can improve the ability to exercise in a hot environment. It might improve performance by dampening the perceived level of thermal strain, allowing individuals to override inhibitory signals.
  
  
  OBJECTIVE
  To investigate whether the enhanced ability to exercise in a hot environment observed when cooling the neck region occurs because of dampening the perceived level of thermal strain experienced and the subsequent overriding of inhibitory signals.
  
  
  METHODS
  Crossover study.
  
  
  METHODS
  Walk-in environmental chamber.
  
  
  METHODS
  Eight endurance-trained, nonacclimated men (age  =  26 ± 2 years, height  =  1.79 ± 0.04 m, mass  =  77.0 ± 6.2 kg, maximal oxygen uptake [V˙O(2max)]  =  56.2 ± 9.2 mL·kg(-1)·min(-1)) participated.
  
  
  METHODS
  Participants completed 4 running tests at approximately 70% V˙O(2max) to volitional exhaustion: 2 familiarization trials followed by 2 experimental trials (cooling collar [CC] and no collar [NC]). Trials were separated by 7 days. Familiarization and NC trials were performed without a collar and used to assess the test variability.
  
  
  METHODS
  Time to volitional exhaustion, heart rate, rectal temperature, neck skin temperature, rating of perceived exertion, thermal sensation, and feeling scale (pleasure/displeasure) were measured.
  
  
  RESULTS
  Time to volitional exhaustion was increased by 13.5% ± 3.8% (CC  =  43.15 ± 12.82 minutes, NC  =  38.20 ± 11.70 minutes; t(7)  =  9.923, P < .001) with the CC, which reduced mean neck skin temperature throughout the test (P < .001). Participants terminated exercise at identical levels of perceived exertion, thermal sensation, and feeling scale, but the CC enabled participants to tolerate higher rectal temperatures (CC  =  39.61°C ± 0.45°C, NC  =  39.18°C ± 0.7°C; t(7)  =  -3.217, P  =  .02) and heart rates (CC  =  181 ± 6 beats/min, NC  =  178 ± 9 beats/min; t(7)  =  -2.664, P  =  .03) at the point of termination.
  
  
  CONCLUSIONS
  Cooling the neck increased the time taken to reach volitional exhaustion by dampening the perceived levels of thermal strain.
authors.affiliation: Human and Life Sciences, Whitelands College, Roehampton University, London, United Kingdom. Chris.Tyler@roehampton.ac.uk
authors.forename: Christopher James
authors.initials: CJ
authors.lastname: Tyler
authors.forename: Caroline
authors.initials: C
authors.lastname: Sunderland
mesh_terms: D000328:Adult; D001831:Body Temperature; D001833:Body Temperature Regulation; D003080:Cold Temperature; D018592:Cross-Over Studies; D015444:Exercise / Q000502:physiology* / Q000523:psychology*; D005080:Exercise Test; D005221:Fatigue; D006339:Heart Rate; D006358:Hot Temperature; D006801:Humans; D008297:Male; D009333:Neck; D010465:Perception; D012420:Running; D012881:Skin Temperature