Author(s): TIMON, R., VILLARINO, J., UTRERO, J., OLCINA, G. , Institution: SPORT SCIENCES FACULTY. UNIVERSITY OF EXTREMADURA, Country: SPAIN, Abstract-ID: 184

INTRODUCTION:
Monitoring core body temperature after exercise is important to avoid heat stroke and to plan appropriate cooling strategies (1). Thermoregulatory response to exercise could be influenced by the training level of athletes via augmented sweating and improved cardiovascular function (2). The aim of the study was to analyze core body and skin temperature after a high-intensity steady-state cycling exercise, comparing the response of individuals based on their level of training.
METHODS:
18 triathletes (28.9 ± 4.8 years, 70.6 ± 5.4 kg, 10.1 ± 2.8 % Fat mass) were divided into two groups based on the watts achieved in an functional threshold power (FTP) test (≥ 4 W/Kg Vs < 4 W/kg). All participants performed a 20-minute steady-state cycling exercise at FTP intensity and in a thermoneutral environment (21.9 ± 0.9 ºC ; 38.5 ± 4.2 % relative humidity) Core body and skin temperature were measured with a non-invasive sensor (CORE, green TEG AG, Switzerland) placed on the chest at different timepoints after exercise.
RESULTS:
The less trained triathletes reached a core body temperature (Post: 37.8 ± 0.3 vs 37.5 ± 0.2 ; 5min: 38.0 ± 0.3 vs 37.8 ± 0.4; 10min: 38.1 ± 0.4 vs 37.9 ± 0.4; 15min: 38.1 ± 0.4 vs 37.8 ± 0.5; 20min: 38.0 ± 0.3 vs 37.8 ± 0.3) and skin temperature (Post: 35.1 ± 0.7 vs 33.9 ± 0.9; 5min: 34.5 ± 0.5 vs 33.1 ± 1.1; 10min: 33.9 ± 0.5 vs 32.1 ± 1.0; 15min: 33.5 ± 0.4 vs 31.6 ± 1.0; 20min: 33.2 ± 0.6 vs 31.8 ± 0.8) significantly higher than the most fit triathletes at all time points after exercise. Likewise it was observed in both groups that core body temperature remained elevated up to 20 minutes after exercise, however, skin temperature decreased progressively after 5 minutes, even below the baseline values.
CONCLUSION:
In conclusion, the results showed that training level influences the thermoregulatory function of athletes, observing a better response to dissipate heat by more fit individuals in termoneutral environment. This research has been supported by the Government of Extremadura (Spain).

1. Périard JD, Eijsvogels TMH, Daanen HAM. Exercise under heat stress: thermoregulation, hydration, performance implications, and mitigation strategies. Physiol Rev. 2021 Oct 1;101(4):1873-1979. doi: 10.1152/physrev.00038.2020. Epub 2021 Apr 8. PMID: 33829868.
2. Kenney WL, Wolf ST, Dillon GA, Berry CW, Alexander LM. Temperature regulation during exercise in the heat: Insights for the aging athlete. J Sci Med Sport. 2021 Aug;24(8):739-746. doi: 10.1016/j.jsams.2020.12.007. Epub 2020 Dec 25. PMID: 33358656; PMCID: PMC8222413.