The Beverage Hydration Index: Influence of Electrolytes, Carbohydrate and Protein

The beverage hydration index (BHI) facilitates a comparison of relative hydration properties of beverages using water as the standard. The additive effects of electrolytes, carbohydrate, and protein on rehydration were assessed using BHI. Nineteen healthy young adults completed four test sessions in randomized order: deionized water (W), electrolytes only (E), carbohydrate-electrolytes (C + E), and 2 g/L dipeptide (alanyl-glutamine)-electrolytes (AG + E). One liter of beverage was consumed, after which urine and body mass were obtained every 60 min through 240 min. Compared to W, BHI was higher (p = 0.007) for C + E (1.15 ± 0.17) after 120 min and for AG + E (p = 0.021) at 240 min (1.15 ± 0.20). BHI did not differ (p > 0.05) among E, C + E, or AG + E; however, E contributed the greatest absolute net effect (>12%) on BHI relative to W. Net fluid balance was lower for W (p = 0.048) compared to C + E and AG + E after 120 min. AG + E and E elicited higher (p < 0.001) overall urine osmolality vs. W. W also elicited greater reports of stomach bloating (p = 0.02) compared to AG + E and C + E. The addition of electrolytes alone (in the range of sports drinks) did not consistently improve BHI versus water; however, the combination with carbohydrate or dipeptides increased fluid retention, although this occurred earlier for the sports drink than the dipeptide beverage. Electrolyte content appears to make the largest contribution in hydration properties of beverages for young adults when consumed at rest.

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Postexercise rehydration: potassium-rich drinks versus water and a sports drink

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2013-0434 ◽

2014 ◽

Vol 39 (10) ◽

pp. 1167-1174 ◽

Cited By ~ 9

Author(s):

Alexandra Pérez-Idárraga ◽

Luis Fernando Aragón-Vargas

Keyword(s):

Weight Loss ◽

Relative Humidity ◽

Body Mass ◽

Fluid Balance ◽

Urine Output ◽

Small Volume ◽

Random Order ◽

Fluid Retention ◽

Physically Active ◽

Sports Drink

Fluid retention, thirst quenching, tolerance, and palatability of different drinks were assessed. On 4 different days, 12 healthy, physically active volunteers (24.4 ± 3.2 years old, 74.75 ± 11.36 kg body mass (mean ± S.D)), were dehydrated to 2.10% ± 0.24% body mass by exercising in an environmental chamber (32.0 ± 0.4 °C dry bulb, 53.8 ± 5.2% relative humidity). Each day they drank 1 of 4 beverages in random order: fresh coconut water (FCW), bottled water (W), sports drink (SD), or potassium-rich drink (NEW); volume was 120% of weight loss. Urine was collected and perceptions self-reported for 3 h. Urine output was higher (p < 0.05) for W (894 ± 178 mL) than SD (605 ± 297 mL) and NEW (599 ± 254 mL). FCW (686 ± 250 mL) was not different from any other drink (p > 0.05). Fluid retention was higher for SD than W (68.2% ± 13.0% vs. 51.3% ± 12.6%, p = 0.013), but not for FCW and NEW (62.5% ± 15.4% and 65.9% ± 15.4%, p > 0.05). All beverages were palatable and well tolerated; none maintained a positive net fluid balance after 3 h, but deficit was greater in W versus SD (p = 0.001). FCW scored higher for sweetness (p = 0.03). Thirst increased immediately after exercise but returned to baseline after drinking a small volume (p < 0.0005). In conclusion, additional potassium in FCW and NEW did not result in additional rehydration benefits over those already found in a conventional sports drink with sodium.

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The Effect of Postexercise Milk Protein Intake on Rehydration of Children

Pediatric Exercise Science ◽

10.1123/pes.2015-0078 ◽

2016 ◽

Vol 28 (2) ◽

pp. 286-295 ◽

Cited By ~ 2

Author(s):

Kimberly Volterman ◽

Daniel Moore ◽

Joyce Obeid ◽

Elizabeth A. Offord ◽

Brian W. Timmons

Keyword(s):

Relative Humidity ◽

Body Mass ◽

Fluid Balance ◽

Protein Intake ◽

Milk Protein ◽

Crossover Design ◽

Fluid Retention ◽

Type Method ◽

Time Interaction ◽

Complete Restoration

Purpose:In adults, rehydration after exercise in the heat can be enhanced with a protein-containing beverage; however, whether this applies to children remains unknown. This study examined the effect of milk protein intake on postexercise rehydration in children.Method:Fifteen children (10–12 years) performed three exercise trials in the heat (34.4 ± 0.2 °C, 47.9 ± 1.1% relative humidity). In a randomized, counterbalanced crossover design, participants consumed iso-caloric and electrolyte-matched beverages containing 0 g (CONT), 0.76 g (Lo-PRO) or 1.5 g (Hi-PRO) of milk protein/100 mL in a volume equal to 150% of their body mass (BM) loss during exercise. BM was then assessed over 4 h of recovery.Results:Fluid balance demonstrated a significant condition × time interaction (p = .012) throughout recovery; Hi-PRO was less negative than CONT at 2 hr (p = .01) and tended to be less negative at 3 h (p = .07). Compared with CONT, beverage retention was enhanced by Hi-PRO at 2 h (p < .05).Conclusion:A postexercise beverage containing milk protein can favorably affect fluid retention in children. Further research is needed to determine the optimal volume and composition of a rehydration beverage for complete restoration of fluid balance.

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The effects of fasting in Ramadan

British Journal Of Nutrition ◽

10.1079/bjn19780162 ◽

1978 ◽

Vol 40 (3) ◽

pp. 583-589 ◽

Cited By ~ 36

Author(s):

K. Y. Mustafa ◽

N. A. Mahmoud ◽

K. A. Gumaa ◽

A. M. A. Gader

Keyword(s):

Young Adults ◽

Fluid Balance ◽

Water Loss ◽

Fluid Intake ◽

Urine Volume ◽

Plasma Osmolality ◽

Good Control ◽

Urine Osmolality ◽

Urine Concentration ◽

Evaporative Water

1. Fluid intake, urine output and evaporative water loss were measured and fluid balance calculated in sixteen subjects for 1 d before Ramadan, during weeks 1–5 of fasting and on the 10th day after the end of Ramadan.2. Plasma osmolality at 06.00 hours, the beginning of the fast, at 18.00 hours, before breaking the fast and at 19.00 hours, 1 h after breaking the fast, and urine osmolality during the day and night were measured before, during and after Ramadan.3. All subjects developed an initial negative fluid balance which was maximum at the beginning of week 3 of fasting and that deficit was compensated for during the later weeks.4. Compensation was brought about by an increase in urine concentration, a decrease in urine volume by day, and salt retention.5. No significant changes were observed in plasma osmolality during the days of fasting and the ‘setting’ of plasma osmolality during Ramadan also was not changed.6. It was concluded that healthy young adults maintain good control of fluid and electroytes during Ramadan.

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The Effect of Ad Libitum Consumption of a Milk-Based Liquid Meal Supplement vs. a Traditional Sports Drink on Fluid Balance After Exercise

International Journal of Sport Nutrition and Exercise Metabolism ◽

10.1123/ijsnem.2015-0229 ◽

2016 ◽

Vol 26 (4) ◽

pp. 347-355 ◽

Cited By ~ 5

Author(s):

Brenton J. Baguley ◽

Jessica Zilujko ◽

Michael D. Leveritt ◽

Ben Desbrow ◽

Christopher Irwin

Keyword(s):

Body Mass ◽

Fluid Balance ◽

Urine Output ◽

Moderate Intensity ◽

Fluid Loss ◽

Liquid Meal ◽

Sports Drink ◽

Gastrointestinal Tolerance ◽

Ad Libitum ◽

Exercise Induced

The aim of this study was to compare the effect of ad libitum intake of a milk-based liquid meal supplement against a carbohydrate-electrolyte sports drink following exercise induced fluid loss. Seven male participants (age 22.3 ± 3.4 years, height 179.3 ± 7.9 cm, body mass 74.3 ± 7.3 kg; mean ± SD) completed 4 separate trials and lost 1.89 ± 0.44% body mass through moderate intensity exercise in the laboratory. After exercise, participants consumed ad libitum over 2 h a milk-based liquid meal supplement (Sustagen Sport) on two of the trials (S1, S2) or a carbohydrate-electrolyte sports drink (Powerade) on two of the trials (P1, P2), with an additional 1 hr observational period. Measures of body mass, urine output, gastrointestinal tolerance and palatability were collected throughout the recovery period. Participants consumed significantly more Powerade than Sustagen Sport over the 2 h rehydration period (P1 = 2225 ± 888 ml, P2 = 2602 ± 1119 mL, S1 = 1375 ± 711 mL, S2 = 1447 ± 857 ml). Total urine output on both Sustagen trails was significantly lower than the second Powerade trial (P2 = 1447 ± 656 ml, S1 = 153 ± 62 ml, S2 = 182 ± 118 mL; p < .05) and trended toward being lower compared with the first Powerade trial (P1 = 1057 ± 699 ml vs. S1, p = .067 and vs. S2, p = .061). No significant differences in net fluid balance were observed between any of the drinks at the conclusion of each trial (P1 = −0.50 ±0. 46 kg, P2 = −0.40 ± 0.35 kg, S1 = −0.61 ± 0.74 kg, S2 = −0.45 ± 0.58 kg). Gastrointestinal tolerance and beverage palatability measures indicated Powerade to be preferred as a rehydration beverage. Ad libitum milk-based liquid meal supplement results in similar net fluid balance as a carbohydrate-electrolyte sports drink after exercise induced fluid loss.

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