Effect of drink pattern and solar radiation on thermoregulation and fluid balance during exercise in chronically heat acclimatized children
✍ Scribed by José R. Rodríguez Santana; Anita M. Rivera-Brown; Walter R. Frontera; Miguel A. Rivera; Pedro M. Mayol; Oded Bar-Or
- Publisher
- John Wiley and Sons
- Year
- 1995
- Tongue
- English
- Weight
- 635 KB
- Volume
- 7
- Category
- Article
- ISSN
- 1042-0533
No coin nor oath required. For personal study only.
✦ Synopsis
The purposes of this study were to examine the thermoregulatory and body fluid balance responses in chronically heat acclimatized children, i.e., indigenous to a tropical climate, during exercise in four outdoor conditions and the effects of dehydration on their thermoregulatory response.
Nine children (age = 13.3 ? 1.9 yr, V0,max = 45.5 ? 9.2 ml . kg-' . rnin-lj cycled a t 60% VOsmax each under four conditions: sun exposure voluntary drinking (SuVD), sun exposure forced drinking (SuFD), shaded voluntary drinking (ShVD), and shaded forced drinking (ShFD). Exercise sessions consisted of four 20-min exercise bouts alternating with 25-min rest periods. Globe temperature and the WBGT index were higher during SuVD and SuFD compared to ShVD and ShFD ( P < 0.05). The change in rectal temperature, metabolic heat production, and heat storage did not differ among the conditions. Total water intake (% IBW) was higher during SuFD (4.1 +-0.01) and ShFD (3.7 5 0.1) compared to SuVD (2.1 % 0.1) and ShVD (1.0 2 0.1) and during SuVD compared to ShVD ( P < 0.05). Sweating rate (L . hr-l) was higher during SuFD (0.7 t 0.1) and ShFD (0.6 i 0.1) compared to SuVD (0.5 ? 0.1) and ShVD (0.4 2 0.1) (P < 0.05). Total fluid loss did not differ among conditions (SuVD = 1.7 i 0.4; SuFD = 1.5 ? 0.4; ShVD = 2.1 ? 0.2; ShFD = 1.3 i 0.3). Results indicate that when exercising in a tropical climate, chronically heat acclimatized children demonstrate mild voluntary dehydration and adequate heat dissipation.