title: Practical Cooling Strategies During Continuous Exercise in Hot Environments: A Systematic Review and Meta-Analysis.
abstract: BACKGROUND
  Performing exercise in thermally stressful environments impairs exercise capacity and performance. Cooling during exercise has the potential to attenuate detrimental increases in body temperature and improve exercise capacity and performance.
  
  
  OBJECTIVE
  The objective of this review was to assess the effectiveness of practical cooling strategies applied during continuous exercise in hot environments on body temperature, heart rate, whole body sweat production, rating of perceived exertion (RPE), thermal perception and exercise performance.
  
  
  METHODS
  Electronic database searches of MEDLINE, SPORTDiscus, Scopus and Physiotherapy Evidence Database (PEDro) were conducted using medical subject headings, indexing terms and keywords. Studies were eligible if participants were defined as 'healthy', the exercise task was conducted in an environment ≥25 °C, it used a cooling strategy that would be practical for athletes to use during competition, cooling was applied during a self-paced or fixed-intensity trial, participants exercised continuously, and the study was a randomised controlled trial with the comparator either a thermoneutral equivalent or no cooling. Data for experimental and comparator groups were meta-analysed and expressed as a standardised mean difference and 95 % confidence interval.
  
  
  RESULTS
  Fourteen studies including 135 participants met the eligibility criteria. Confidence intervals for meta-analysed data included beneficial and detrimental effects for cooling during exercise on core temperature, mean skin temperature, heart rate and sweat production during fixed-intensity exercise. Cooling benefited RPE and thermal perception during fixed-intensity exercise and improved self-paced exercise performance.
  
  
  CONCLUSIONS
  Cooling during fixed-intensity exercise, particularly before a self-paced exercise trial, improves endurance performance in hot environments by benefiting RPE and thermal perception, but does not appear to attenuate increases in body temperature.
authors.affiliation: Centre for Sport and Exercise Science, Sheffield Hallam University, A016 Collegiate Hall, Sheffield, S10 2BP, UK. a.ruddock@shu.ac.uk.
authors.forename: Alan
authors.initials: A
authors.lastname: Ruddock
authors.affiliation: Centre for Sport and Exercise Science, Sheffield Hallam University, A016 Collegiate Hall, Sheffield, S10 2BP, UK.
authors.forename: Brent
authors.initials: B
authors.lastname: Robbins
authors.affiliation: Department of Sport, Exercise and Rehabilitation, Northumbria University, Room 244 Northumberland Building, Newcastle upon Tyne, NE1 8ST, UK.
authors.forename: Garry
authors.initials: G
authors.lastname: Tew
authors.affiliation: Centre for Sport and Exercise Science, Sheffield Hallam University, A121 Collegiate Hall, Sheffield, S10 2BP, UK.
authors.forename: Liam
authors.initials: L
authors.lastname: Bourke
authors.affiliation: Faculty of Health and Wellbeing, Sheffield Hallam University, F616 Robert Winston Building, Sheffield, S10 2BP, UK.
authors.forename: Alison
authors.initials: A
authors.lastname: Purvis
mesh_terms: D054874:Athletic Performance / Q000502:physiology*; D001831:Body Temperature; D001833:Body Temperature Regulation / Q000502:physiology*; D003080:Cold Temperature; D015444:Exercise / Q000502:physiology*; D006358:Hot Temperature; D006801:Humans; D012881:Skin Temperature / Q000502:physiology