Plateau in Core Temperature during Shorter but Not Longer Work/Rest Cycles in Heat.
Int J Environ Res Public Health
; 21(3)2024 Mar 20.
Article
em En
| MEDLINE
| ID: mdl-38541370
ABSTRACT
This study compared physiological responses to two work/rest cycles of a 21 work-to-rest ratio in a hot environment. In a randomized crossover design, fourteen participants completed 120 min of walking and rest in the heat (36.3 ± 0.6 °C, 30.2 ± 4.0% relative humidity). Work/rest cycles were (1) 40 min work/20 min rest [40/20], or (2) 20 min work/10 min rest [20/10], both completing identical work. Core temperature (Tc), skin temperature (Tsk), heart rate (HR), nude body mass, and perception of work were collected. Comparisons were made between trials at equal durations of work using three-way mixed model ANOVA. Tc plateaued in [20/10] during the second hour of work (p = 0.93), while Tc increased in [40/20] (p < 0.01). There was no difference in maximum Tc ([40/20] 38.08 ± 0.35 °C, [20/10] 37.99 ± 0.27 °C, p = 0.22) or end-of-work Tsk ([40/20] 36.1 ± 0.8 °C, [20/10] 36.0 ± 0.7 °C, p = 0.45). End-of-work HR was greater in [40/20] (145 ± 25 b·min-1) compared to [20/10] (141 ± 27 b·min-1, p = 0.04). Shorter work/rest cycles caused a plateau in Tc while longer work/rest cycles resulted in a continued increase in Tc throughout the work, indicating that either work structure could be used during shorter work tasks, while work greater than 2 h in duration may benefit from shorter work/rest cycles to mitigate hyperthermia.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Temperatura Corporal
/
Temperatura Alta
Limite:
Humans
Idioma:
En
Ano de publicação:
2024
Tipo de documento:
Article