Physiological responses to 10 days of heart rate–clamped heat acclimation in hot–dry and hot–humid environments
Abstract
To examine changes in power output, thermal, physiological, and perceptual responses during a 10-day heart-rate-clamped training protocol in hot-dry (HD), hot-humid (HH), and thermoneutral (TN) conditions. Thirty trained participants were allocated to TN (20 degrees C, 40% RH), HD (40 degrees C, 35% RH), or HH (31.5 degrees C, 95% RH) (n = 10 per group), with HD and HH matched for WBGT (similar to 31 degrees C). Participants completed 10 days of 60-min cycling at a heart-rate-clamped intensity (similar to 65% VO2max in HD and HH; similar to 60% VO2max in TN). Power output and physiological responses were assessed on Days 1, 5, and 10. Mean power output increased from Day 1 to Day 5 (similar to 27%, p = 0.020), with no further change thereafter. Increases were similar in HD and HH, with minimal change in TN. Rectal temperature rose similarly across conditions (similar to 0.7-0.8 degrees C), despite higher absolute values in HD. Skin temperature was higher in HD, plateauing by Day 5, but increased progressively in HH to Day 10. Perceptual strain was higher in HD and HH than TN (p < 0.001), with thermal comfort improving by Day 10. Power output improved rapidly within 5 days. Despite similar rectal temperature, responses stabilized earlier in HD, whereas HH required a full 10-day period.
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BibTeX
@article{anbalagan2026physiological,
title = {{Physiological responses to 10 days of heart rate–clamped heat acclimation in hot–dry and hot–humid environments}},
author = {Prashan Anbalagan and Peter Peeling and Mohammed Ihsan and Sébastien Racinais and Karen Wallman and Alex Shaykevich and Olivier Girard},
journal = {Journal of Sports Sciences},
year = {2026},
month = sep,
doi = {10.1080/02640414.2026.2733957},
url = {https://hal.inrae.fr/hal-05797639v1},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - JOUR
TI - Physiological responses to 10 days of heart rate–clamped heat acclimation in hot–dry and hot–humid environments
AU - Prashan Anbalagan
AU - Peter Peeling
AU - Mohammed Ihsan
AU - Sébastien Racinais
AU - Karen Wallman
AU - Alex Shaykevich
AU - Olivier Girard
PY - 2026
DA - 2026/09/27
JO - Journal of Sports Sciences
DO - 10.1080/02640414.2026.2733957
UR - https://hal.inrae.fr/hal-05797639v1
AB - To examine changes in power output, thermal, physiological, and perceptual responses during a 10-day heart-rate-clamped training protocol in hot-dry (HD), hot-humid (HH), and thermoneutral (TN) conditions. Thirty trained participants were allocated to TN (20 degrees C, 40% RH), HD (40 degrees C, 35% RH), or HH (31.5 degrees C, 95% RH) (n = 10 per group), with HD and HH matched for WBGT (similar to 31 degrees C). Participants completed 10 days of 60-min cycling at a heart-rate-clamped intensity (similar to 65% VO2max in HD and HH; similar to 60% VO2max in TN). Power output and physiological responses were assessed on Days 1, 5, and 10. Mean power output increased from Day 1 to Day 5 (similar to 27%, p = 0.020), with no further change thereafter. Increases were similar in HD and HH, with minimal change in TN. Rectal temperature rose similarly across conditions (similar to 0.7-0.8 degrees C), despite higher absolute values in HD. Skin temperature was higher in HD, plateauing by Day 5, but increased progressively in HH to Day 10. Perceptual strain was higher in HD and HH than TN (p < 0.001), with thermal comfort improving by Day 10. Power output improved rapidly within 5 days. Despite similar rectal temperature, responses stabilized earlier in HD, whereas HH required a full 10-day period.
SN - 0264-0414
SN - 1466-447X
ER -