2025/11/01 by Normand A. Richard, Stephen S. Cheung, Michael S. Koehle +3 · 1 voice
Medicine · #Exercise and Physiological Responses #Infrared Thermography in Medicine #Thermoregulation and physiological responses
paper · pdf · doi:10.14814/phy2.70631
openalex publication_date 2025/11/01 · openalex created_date 2025/11/19 · openalex updated_date 2026/08/01
Abstract We investigated whether heat adaptation (HA) could be maintained in trained females following an initial acclimation period. The experimental group (EXP, n = 11) completed 10 sessions of HA over 2 weeks, followed by nine sessions of HA maintenance (HA M ) over 3 weeks. HA was induced with home‐based stationary cycling while overdressing. A control group (CON, n = 4) was exposed to heart rate‐matched thermoneutral training. Prior to and at the end of the acclimation period (PRE, MID) and following the maintenance period (POST), , peak power output (PPO), and hemoglobin mass (Hb mass ) were determined in 18°C, before a 20 km time trial (TT) in 35°C, 45% RH. During the TT, rectal and mean skin temperature (T re , sk ), heart rate, peak cardiac output (), and sweat rate were measured. PPO increased ( p = 0.0003) and TT times decreased ( p < 0.0001) from PRE to MID and POST in EXP but not CON. , T re , sk , heart rate, and remained stable in both groups. Sweat rate only increased in EXP from PRE to POST ( p = 0.0197). Hb mass did not change in EXP. HA M potentiated hot exercise performance compared to HA, as demonstrated by improvements in both temperate and hot conditions. While HA M suffices to further develop thermal resistance, it is unsuitable to increase Hb mass following 10 days of HA or 3 weeks of HA M . Our findings demonstrate that females can achieve HA by overdressing at home for 10 days and that HA M provides further benefits.