Sports Medicine

, Volume 45, Issue 3, pp 303–311 | Cite as

Adaptation to Hot Environmental Conditions: An Exploration of the Performance Basis, Procedures and Future Directions to Optimise Opportunities for Elite Athletes

  • Joshua H. Guy
  • Glen B. Deakin
  • Andrew M. EdwardsEmail author
  • Catherine M. Miller
  • David B. Pyne
Leading Article


Extreme environmental conditions present athletes with diverse challenges; however, not all sporting events are limited by thermoregulatory parameters. The purpose of this leading article is to identify specific instances where hot environmental conditions either compromise or augment performance and, where heat acclimation appears justified, evaluate the effectiveness of pre-event acclimation processes. To identify events likely to be receptive to pre-competition heat adaptation protocols, we clustered and quantified the magnitude of difference in performance of elite athletes competing in International Association of Athletics Federations (IAAF) World Championships (1999–2011) in hot environments (>25 °C) with those in cooler temperate conditions (<25 °C). Athletes in endurance events performed worse in hot conditions (~3 % reduction in performance, Cohen’s d > 0.8; large impairment), while in contrast, performance in short-duration sprint events was augmented in the heat compared with temperate conditions (~1 % improvement, Cohen’s d > 0.8; large performance gain). As endurance events were identified as compromised by the heat, we evaluated common short-term heat acclimation (≤7 days, STHA) and medium-term heat acclimation (8–14 days, MTHA) protocols. This process identified beneficial effects of heat acclimation on performance using both STHA (2.4 ± 3.5 %) and MTHA protocols (10.2 ± 14.0 %). These effects were differentially greater for MTHA, which also demonstrated larger reductions in both endpoint exercise heart rate (STHA: −3.5 ± 1.8 % vs MTHA: −7.0 ± 1.9 %) and endpoint core temperature (STHA: −0.7 ± 0.7 % vs −0.8 ± 0.3 %). It appears that worthwhile acclimation is achievable for endurance athletes via both short-and medium-length protocols but more is gained using MTHA. Conversely, it is also conceivable that heat acclimation may be counterproductive for sprinters. As high-performance athletes are often time-poor, shorter duration protocols may be of practical preference for endurance athletes where satisfactory outcomes can be achieved.


Elite Athlete Heat Exposure Heat Acclimation Pace Strategy Plasma Volume Expansion 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



No funding was provided for the preparation of the paper. No author has any conflicts of interest. All authors contributed fully to the preparation of this manuscript.


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Copyright information

© Springer International Publishing Switzerland 2014

Authors and Affiliations

  • Joshua H. Guy
    • 1
  • Glen B. Deakin
    • 1
  • Andrew M. Edwards
    • 1
    • 4
    Email author
  • Catherine M. Miller
    • 2
  • David B. Pyne
    • 1
    • 3
  1. 1.Sport and Exercise ScienceJames Cook UniversityCairnsAustralia
  2. 2.College of Public HealthMedical and Veterinary Sciences, James Cook UniversityCairnsAustralia
  3. 3.Department of PhysiologyAustralian Institute of SportCanberraAustralia
  4. 4.Sport and Health SciencesSt Mark and St John UniversityPlymouthUK

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