Abstract
The intent of this study was to assess the influence of drink flavor and composition on voluntary drinking and hydration status in girls exercising intermittently in the heat (35 ± 1°C, 45–50% relative humidity). Twelve physically active, nonacclimatized girls (9–12 years) performed three 3 h identical sessions, each consisting of four 20 min cycling bouts at 50% \( (\ifmmode\expandafter\dot\else\expandafter\.\fi{V}{\text{O}}_{{{\text{2}}\max }} ), \) separated by 25 min of rest. One of the three beverages (chilled to 8–10°C) was assigned to each session: unflavored water (W), grape-flavored water (FW) and grape-flavored water plus 6% carbohydrate and 18 mmol l−1 NaCl (CNa). Drinking was ad libitum. Body weight (BW), drink intake (DI), heart rate, rectal and skin temperatures, and perceptions of thirst and stomach fullness were monitored periodically. Total DI was 759, 940, 1,045 g in W, FW and CNa, respectively (P < 0.05 for CNa–W and FW–W). BW changes were −0.15, 0.16, and 0.45% in W, FW and CNa, respectively, but only the difference between CNa and W was significant (P < 0.05). Other physiological and perceptual variables were not different between trials. In conclusion, beverage flavoring regardless if its combination with carbohydrate and NaCl, mildly enhanced voluntary drinking in young non-acclimatized girls. In contrast to previous research in young boys, euhydration was maintained in the girls by an adequate intake of unflavored water.
Similar content being viewed by others
References
American Academy of Pediatrics (2000) Climatic heat stress and the exercising child and adolescent. Pol Statement Pediatr 106:158–159
American College of Sports Medicine (1996) Exercise and fluid replacement. Med Sci Sports Exerc 28:i–vii
Armstrong LE, Hubbard RW, Szlyk PC, Matthew WT, Sils IV (1985) Voluntary dehydration and electrolyte losses during prolonged exercise in the heat. Aviat Space Environ Med 56:765–770
Baker LB, Munce TA, Kenney WL (2005) Sex differences in voluntary fluid intake by older adults during exercise. Med Sci Sports Exerc 37:789–796
Bar-Or O (1983) Pediatric sports medicine for the practitioner. From physiologic principles to clinical applications. Springer, New York
Bar-Or O (1996) Thermoregulation in females from a life span persepctive. In: Exercise and the female: a life span approach. Cooper Publishing Group, Carmel, pp. 249–284
Bar-Or O (1998) Effects of age and gender on sweating pattern during exercise. Int J Sports Med 19(Suppl 2):S106–S107
Bar-Or O, Dotan R, Inbar O, Rotshtein A, Zonder H (1980) Voluntary hypohydration in 10- to 12-year-old boys. J Appl Physiol 48:104–108
Bar-Or O, Blimkie CJ, Hay JA, Macdougall JD, Ward DS, Wilson WM (1992) Voluntary dehydration and heat intolerance in cystic fibrosis. Lancet 339:696–699
Boulze D, Montastruc P, Cabanac M (1983) Water intake, pleasure and water temperature in humans. Physiol Behav 30:97–102
Davis DP, Videen JS, Marino A, Vilke GM, Dunford JV, Van Camp SP, Maharam LG (2001) Exercise-associated hyponatremia in marathon runners: a two-year experience. J Emerg Med 21:47–57
Greenleaf JE, Sargent F II (1965) Voluntary dehydration in man. J Appl Physiol 20:719–724
Hardy JD, Dubois EF (1938) The technique of measuring radiation and convection. J Nutr 15:461–475
Hubbard RW, Sandick BL, Matthew WT, Francesconi RP, Sampson JB, Durkot MJ, Maller O, Engell DB (1984) Voluntary dehydration and alliesthesia for water. J Appl Physiol 57:868–873
Kawahata A (1960) Sex differences in sweating. In: Yoshimura H, Ogata K, Itoh S (eds) Essential problems in climatic physiology. Nankodo, Kyoto, pp 169–184
Kriemler S, Wilk B, Schurer W, Wilson WM, Bar-Or O (1999) Preventing dehydration in children with cystic fibrosis who exercise in the heat. Med Sci Sports Exerc 31:774–779
Lee JK, Shirreffs SM (2007) The influence of drink temperature on thermoregulatory responses during prolonged exercise in moderate environment. J Sports Sci 25(9):975–985
Matsudo SMM, MatsudoVKR (1994) Self-assessment and physician assessment of sexual maturation in Brazilian boys and girls: concordance and reproducibility. Am J Hum Biol 6:451–455
Maughan RJ, Noakes TD (1991) Fluid replacement and exercise stress. Sports Med 12:16–31
Maughan RJ, Leiper JB, Shirreffs SM (1997) Factors influencing the restoration of fluid and electrolyte balance after exercise in the heat. Br J Sports Med 31:175–182
Meyer F, Bar-Or O, Salsberg A, Passe D (1994) Hypohydration during exercise in children: effect on thirst, drink preferences, and rehydration. Int J Sports Nutr 4:22–35
Meyer F, Bar-Or O, Wilk B (1995) Children’s perceptual responses to ingesting drinks of different compositions during and following exercise in the heat. Int J Sport Nutr 5:13–24
Mitchell JW, Nadel ER, Stolwijk JAJ (1972) Respiratory weight losses during exercise. J Appl Physiol 32:474–476
Murray R (1998) Rehydration strategies––balancing substrate, fluid, and electrolyte provision. Int J Sports Med 19(Suppl 2):S133–S135
Nadel ER, Mack GW, Nose H (1995) Influence of fluid replacement beverages on body fluid homeostasis during exercise and recovery. Perspect Exerc 181:205
Noakes TD (1993) Fluid replacement during exercise. Exerc Sport Sci Rev 21:297–330
Rivera-Brown A, Gutierrez R, Gutierrez JC, Frontera WR, Bar-Or O (1999) Drink composition, voluntary drinking, and fluid balance in exercising, trained, heat-acclimatized boys. J Appl Physiol 86:78–84
Rodriguez Santana JR, Rivera-Brown AM, Frontera WR, Rivera MA, Mayol PM, Bar-Or O (1995) Effect of drink pattern and solar radiation on thermoregulation and fluid balance during exercise in chronically heat acclimatized children. Am J Hum Biol 7:643–650
Rothstein A, Adolph EF, Wills JH (1947) Voluntary dehydration. In: Adolph EF (ed) Physiology of man in the desert. Interscience, New York, pp 254–270
Sandick BL, Engell DB, Maller O (1984) Perception of drinking water temperature and effects for humans after exercise. Physiol Behav 32:851–855
Sawka MN, Pandolf KB (1990) Effect of body water loss on physiological function and exercise performance. In: Gisolfi CV, Lamb DR (eds) Perspectives in exercise and sport medicine: fluid homeostasis during exercise. Benchmark, Indianapolis, pp 1–30
Speedy DB, Noakes TD, Schneider C (2001) Exercise-associated hyponatremia: a review. Emerg Med (Fremantle.) 13:17–27
Stolwijk JA, Hardy JD (1966) Partitional calorimetric studies of responses of man to thermal transients. J Appl Physiol 21:967–977
Szlyk PC, Sils IV, Francesconi RP, Hubbard RW, Armstrong LE (1989) Effects of water temperature and flavoring on voluntary dehydration in men. Physiol Behav 45:639–647
Wilk B, Bar-Or O (1996) Effect of drink flavor and NaCl on voluntary drinking and hydration in boys exercising in the heat. J Appl Physiol 80:1112–1117
Wilk B, Kriemler S, Keller H, Bar-Or O (1998) Consistency in preventing voluntary dehydration in boys who drink a flavored carbohydrate–NaCl beverage during exercise in the heat. Int J Sport Nutr 8:1–9
Wilk B, Yuxiu H, Bar-Or O (2002) Effect of body hypohydration on aerobic performance of boys who exercise in the heat. Med Sci Sports Exerc 34(S48)
Wilmore JH, Morton AR, Gilbey HJ, Wood RJ (1998) Role of taste preference on fluid intake during and after 90 min of running at 60% of VO2 max in the heat. Med Sci Sports Exer 30:587–595
Yousef MK, Dill DB, Vitez TS, Hillyard SD, Goldman AS (1984) Thermoregulatory responses to desert heat: age, race and sex. J Gerontol 39:406–414
Acknowledgments
We thank all the girls who were willing to perform this long and demanding task and to their parents, who supported them in the effort. The authors also thank Dr. Brian Timmons for his valuable comments and help in preparation of this manuscript. This study was supported by the Gatorade Sports Science Institute.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Wilk, B., Rivera-Brown, A.M. & Bar-Or, O. Voluntary drinking and hydration in non-acclimatized girls exercising in the heat. Eur J Appl Physiol 101, 727–734 (2007). https://doi.org/10.1007/s00421-007-0539-z
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00421-007-0539-z