Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2020 Jul-Aug;96(4):464-471.
doi: 10.1016/j.jped.2018.12.011. Epub 2019 Apr 18.

Thermoregulatory and perceptual responses of lean and obese fit and unfit girls exercising in the heat

Carolina de Ávila Rodrigues  1 , Gabriela Tomedi Leites  2 , Flavia Meyer  1
Affiliations

Thermoregulatory and perceptual responses of lean and obese fit and unfit girls exercising in the heat

Carolina de Ávila Rodrigues et al. J Pediatr (Rio J). 2020 Jul-Aug.

Abstract
in English, Portuguese

Objective: To verify the thermoregulatory and perceptual responses of obese and lean girls, either fit or unfit, exercising in the heat at a similar rate of metabolic heat production per unit body mass.

Methods: A total of 34 pubescent girls were allocated in four groups: 12 obese fit, 9 obese unfit, 5 lean fit, and 8 lean unfit. The obese groups (13.2±1.4 years, 40.5%±5.8% fat by DXA) differed in their aerobic fitness (V˙O2peak 76.0±8.1 vs. 56.6±5.8mL.kgmusclemass-1.min-1), as well as the lean groups (13.1±1.6 years, 24.0%±4.8% fat) (V˙O2peak 74.5±2.9 vs. 56.2±5.0mL.kgmuscle mass-1min-1). Girls cycled two bouts of 25min with a 10min rest in between, at ∼5.4W.kg-1 in the heat (36°C and 40% relative humidity) and they were kept euhydrated. Rectal and skin temperatures and heart rate were measured every 5min. Perceptual responses were evaluated throughout the exercise.

Results: Initial rectal temperature was higher in the obese subjects compared to the lean subjects (37.5±0.3 and 37.2±0.3°C). No difference was observed among the girls whom were obese (eight fit or unfit) and lean (also fit or unfit) throughout the exercise in rectal temperature (37.6±0.2, 37.5±0.3, 37.5±0.3, 37.4±0.3°C, respectively), skin temperature (34.8±0.8, 35.1±1.0, 34.4±0.9, 35.2±0.9°C), and heart rate (128±18; 118±12, 130±16, 119±16beatsmin-1). No differences were observed in perceptual responses among groups.

Conclusion: Regardless of the adiposity or aerobic fitness, pubescent girls had similar thermoregulatory and perceptual responses while cycling in the heat at similar metabolic heat production.

Objetivo: Verificar as respostas termorregulatórias e perceptivas de meninas obesas e magras, com alta e baixa aptidão aeróbica, exercitando-se no calor com produção metabólica de calor similar por massa corporal.

Métodos: Um total de 34 meninas púberes foram alocadas em quatro grupos: 12 obesas com alta aptidão aeróbica, 9 obesas com baixa aptidão aeróbica, 5 magras com alta aptidão aeróbica e 8 magras com baixa aptidão aeróbica. Os grupos obesos (13,2 ± 1,4 anos, 40,5% ± 5,8% de gordura por DXA) diferiram em sua aptidão aeróbica (V˙O2peak 76,0 ± 8,1 vs. 56,6 ± 5,8 mL.kg de massa muscular-1.min-1), bem como os grupos magros (13,1 ± 1,6 anos, 24,0% ± 4,8% de gordura) (V˙O2peak 74,5 ± 2,9 vs. 56,2 ± 5,0 mL.kg de massa muscular-1min-1). As meninas pedalaram duas sessões de 25 minutos com descanso de 10 minutos entre as sessões, a ∼5,4 W.kg-1 no calor (36 °C e 40% de umidade relativa) e foram mantidas hidratadas. As temperaturas retal e cutânea e a frequência cardíaca foram medidas a cada 5 minutos. As respostas perceptivas foram avaliadas durante o exercício.

Resultados: A temperatura retal inicial foi maior nas meninas obesas em comparação com as magras (37,5 ± 0,3 e 37,2 ± 0,3 °C). Não houve diferença entre as meninas obesas (com alta aptidão aeróbica ou não) e magras (também com alta aptidão aeróbica ou não) durante todo o exercício em relação à temperatura retal (37,6 ± 0,2; 37,5 ± 0,3; 37,5 ± 0,3; 37,4 ± 0,3 °C; respectivamente), temperatura da pele (34,8 ± 0,8; 35,1 ± 1,0; 34,4 ± 0,9; 35,2 ± 0,9 °C), e frequência cardíaca (128 ± 18; 118 ± 12, 130 ± 16, 119 ± 16 batimentos.min-1). Não foram observadas diferenças nas respostas perceptivas entre os grupos.

Conclusão: Independentemente da adiposidade ou do condicionamento aeróbico, as meninas púberes tiveram respostas termorregulatórias e perceptivas semelhantes, enquanto pedalavam no calor com uma produção metabólica de calor similar.

Keywords: Exercise; Exercício; Obesidade; Obesity; Pubescent; Púbere; Termorregulação; Thermoregulation.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Physiological responses during exercise in the heat (aObese > Lean).
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Dougherty K.A., Chow M., Larry Kenney W. Critical environmental limits for exercising heat-acclimated lean and obese boys. Eur J Appl Physiol. 2010;108:779–789. - PMC - PubMed
    1. Sehl P., Leites G., Martins J., Meyer F. Responses of obese and non-obese boys cycling in the heat. Int J Sports Med. 2012;33:497–501. - PubMed
    1. Council on Sports Medicine and Fitness and Council on School Health, Bergeron M.F., Devore C., Rice S.G., American Academy of Pediatrics Policy statement – climatic heat stress and exercising children and adolescents. Pediatrics. 2011;128:e741–e747. - PubMed
    1. Dumith S.C., Domingues M.R., Gigante D.P., Hallal P.C., Menezes A.M., Kohl H.W. Prevalence and correlates of physical activity among adolescents from Southern Brazil. Rev Saúde Pública. 2010;44:457–467. - PubMed
    1. Bar-Or O., Rowland T. Pediatric exercise medicine: from physiologic principles to health care application, Champaign, Il. Hum Kinet. 2004