title: The effects of temporal neck cooling on cognitive function during strenuous exercise in a hot environment: a pilot study.
abstract: BACKGROUND
  Heat stress potentially has detrimental effects on brain function. Hence, cognitive function may be impaired during physical activity in a hot environment. Skin cooling is often applied in a hot environment to counteract heat stress. However, it is unclear to what extent neck cooling is effective for cognitive impairment during exercise in a hot environment. The purpose of this study was to examine the effects of temporal neck cooling on cognitive function during strenuous exercise in a hot environment.
  
  
  METHODS
  Eight male young participants (mean ± SD, age = 26.1 ± 3.2 years; peak oxygen uptake = 45.6 ± 5.2 ml/kg/min) performed Spatial delayed response (DR) task (working memory) and Go/No-Go task (executive function) at rest and during exercise in the Hot and Hot + Cooling conditions. After the participants completed the cognitive tasks at rest, they cycled the ergometer until their heart rate (HR) reached 160 beats/min. Then, they cycled for 10 min while keeping their HR at 160 beats/min. The cognitive tasks were performed 3 min after their HR reached 160 beats/min. The air temperature was maintained at 35°C and the relative humidity was controlled at 70%. Neck cooling was applied to the backside of the neck by a wet towel and fanning. We used accuracy of the Spatial DR and Go/No-Go tasks and reaction time in the Go/No-Go task to assess cognitive function.
  
  
  RESULTS
  Neck cooling temporarily decreased the skin temperature during exercise. The accuracy of the cognitive tasks was lower during exercise than that at rest in the Hot and Hot + Cooling condition (p < 0.05). There were no differences in the accuracy between the Hot and Hot + Cooling conditions (p = 0.98). Neither exercise (p = 0.40) nor cooling (p = 0.86) affected reaction time. These results indicate that temporal neck cooling did not alter cognitive function during strenuous exercise in a hot environment.
  
  
  CONCLUSIONS
  The present study suggests that temporal neck cooling with a wet towel and fanning is not effective for attenuating impairment of working memory and executive function during strenuous exercise with a short duration in a warm and humid environment.
authors.affiliation: Faculty of Sports and Health Science, Fukuoka University, Fukuoka, Japan. soichi.ando@uec.ac.jp.|Graduate School of Informatics and Engineering, The University of Electro-Communications, 1-5-1 Chofugaoka, Chofu, Tokyo, 182-8585, Japan. soichi.ando@uec.ac.jp.
authors.forename: Soichi
authors.initials: S
authors.lastname: Ando
authors.affiliation: Graduate School of Sports and Health Science, Fukuoka University, Fukuoka, Japan. mt.komi51@gmail.com.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Komiyama
authors.affiliation: Fukuoka University Institute for Physical Activity, Fukuoka University, Fukuoka, Japan. mizuki97@hotmail.com.|Physical Fitness Research Institute, Meiji Yasuda Life Foundation of Health and Welfare, Tokyo, Japan. mizuki97@hotmail.com.
authors.forename: Mizuki
authors.initials: M
authors.lastname: Sudo
authors.affiliation: Faculty of Sports and Health Science, Fukuoka University, Fukuoka, Japan. kiyonaga@fukuoka-u.ac.jp.|Fukuoka University Institute for Physical Activity, Fukuoka University, Fukuoka, Japan. kiyonaga@fukuoka-u.ac.jp.
authors.forename: Akira
authors.initials: A
authors.lastname: Kiyonaga
authors.affiliation: Faculty of Sports and Health Science, Fukuoka University, Fukuoka, Japan. htanaka@fukuoka-u.ac.jp.|Fukuoka University Institute for Physical Activity, Fukuoka University, Fukuoka, Japan. htanaka@fukuoka-u.ac.jp.
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Tanaka
authors.affiliation: Faculty of Sports and Health Science, Fukuoka University, Fukuoka, Japan. higaki@fukuoka-u.ac.jp.|Fukuoka University Institute for Physical Activity, Fukuoka University, Fukuoka, Japan. higaki@fukuoka-u.ac.jp.
authors.forename: Yasuki
authors.initials: Y
authors.lastname: Higaki
mesh_terms: D000328:Adult; D001831:Body Temperature; D001835:Body Weight; D003071:Cognition / Q000502:physiology*; D003080:Cold Temperature; D004777:Environment; D015444:Exercise; D006339:Heart Rate / Q000502:physiology; D006358:Hot Temperature; D006801:Humans; D019344:Lactic Acid / Q000097:blood; D008297:Male; D009333:Neck / Q000502:physiology*; D005082:Physical Exertion; D010865:Pilot Projects; D013647:Task Performance and Analysis; D013997:Time Factors
chemical_list: D019344:Lactic Acid