A common practice among endurance athletes is to purposefully train in hot environments during a “heat stress camp.” However, combined exercise-heat stress poses threats to athlete well-being, and therefore, heat stress training has the potential to induce maladaptation. This case study describes the monitoring strategies used in a successful 3-week heat stress camp undertaken by 2 elite Ironman triathletes, namely resting heart rate variability, self-report well-being, and careful prescription of training based on previously collected physiological data. Despite the added heat stress, training volume very likely increased in both athletes, and training load very likely increased in one of the athletes, while resting heart rate variability and self-report well-being were maintained. There was also some evidence of favorable metabolic changes during routine laboratory testing following the camp. The authors therefore recommend that practitioners working with endurance athletes embarking on a heat stress training camp consider using the simple strategies employed in the present case study to reduce the risk of maladaptation and nonfunctional overreaching.
Maunder, Kilding, and Plews are with Sports Performance Research Institute New Zealand, Auckland University of Technology, Auckland, New Zealand. Stevens is with the School of Health and Human Sciences, Southern Cross University, Coffs Harbour, New South Wales, Australia; and the Centre for Athlete Development, Experience & Performance, Southern Cross University, Coffs Harbour, New South Wales, Australia.
Lim CL, Pyne D, Horn P, et al. The effects of increased endurance training load on biomarkers of heat intolerance during intense exercise in the heat. Appl Physiol Nutr Metab. 2009;34(4):616–624. doi:10.1139/H09-021
LimCL, PyneD, HornP, et al. The effects of increased endurance training load on biomarkers of heat intolerance during intense exercise in the heat. . 2009;34(4):616–624. doi:10.1139/H09-02110.1139/H09-02119767796)| false
Sylta Ø, Tonnessen E, Seiler S. From heart-rate data to training quantification: a comparison of 3 methods of training-intensity analysis. Int J Sports Physiol Perform. 2014;9(1):100–107. doi:10.1123/IJSPP.2013-0298
SyltaØ, TonnessenE, SeilerS. From heart-rate data to training quantification: a comparison of 3 methods of training-intensity analysis. . 2014;9(1):100–107. doi:10.1123/IJSPP.2013-029810.1123/ijspp.2013-029824408353)| false
Plews DJ, Laursen PB, Stanley J, Kilding AE, Buchheit M. Training adaptation and heart rate variability in elite endurance athletes: opening the door to effective monitoring. Sports Med. 2013;43(9):773–781. doi:10.1007/s40279-013-0071-8
PlewsDJ, LaursenPB, StanleyJ, KildingAE, BuchheitM. Training adaptation and heart rate variability in elite endurance athletes: opening the door to effective monitoring. . 2013;43(9):773–781. doi:10.1007/s40279-013-0071-810.1007/s40279-013-0071-823852425)| false
Reeve T, Gordon R, Laursen PB, Lee JKW, Tyler CJ. Impairment of cycling capacity in the heat in well-trained endurance athletes after high-intensity short-term heat acclimation. [published online ahead of print January31, 2019]. Int J Sports Physiol Perform. PubMed ID: 30702375 doi:10.1123/ijspp.2018-0537
Lucía A, Hoyos J, Pérez M, Chicharro JL. Heart rate and performance parameters in elite cyclists: a longitudinal study. Med Sci Sports Exerc. 2000;32(10):1777–1782. doi:10.1097/00005768-200010000-00018
JeukendrupAE, WallisGA. Measurement of substrate oxidation during exercise by means of gas exchange measurements. . 2005;26(suppl 1):S28–S37. doi:10.1055/s-2004-8305121570245410.1055/s-2004-830512)| false
McLean BS, Coutts AJ, Kelly V, McGuigan MR, Cormack S. Neuromuscular, endocrine, and perceptual fatigue responses during different length between-match microcycles in professional rugby league players. Int J Sports Physiol Perform. 2010;5(3):367–383. doi:10.1123/ijspp.5.3367
McLeanBS, CouttsAJ, KellyV, McGuiganMR, CormackS. Neuromuscular, endocrine, and perceptual fatigue responses during different length between-match microcycles in professional rugby league players. . 2010;5(3):367–383. doi:10.1123/ijspp.5.336710.1123/ijspp.5.3.36720861526)| false
Plews DJ, Scott B, Altini M, Wood M, Kilding AE, Laursen PB. Comparison of heart-rate-variability recording with smartphone photoplethysmography, Polar H7 chest strap, and electrocardiography. Int J Sports Physiol Perform. 2017;12(10):1324–1328. doi:10.1123/ijspp.2016-0668
Pallarés JG, Morán-Navarro R, Ortega JF, Fernández-Elías VE, Mora-Rodriguez R. Validity and reliability of ventilatory and blood lactate thresholds in well-trained cyclists. PLoS ONE. 2016;11(9):1–16. doi:10.1371/journal.pone.0163389
PattonMG, GillumTL, SzymanskiMC, et al. Heat acclimation increases mitochondrial respiration capacity of C2C12 myotubes and protects against LPS-mediated energy deficit. . 2018;23(5):871–883. doi:10.1007/s12192-018-0894-12964456310.1007/s12192-018-0894-1)| false