scholarly journals Fluid Restriction Negatively Influences Perceived Morning Alertness and Visuomotor Ability

2021 ◽  
Vol 19 (1) ◽  
pp. 370
Author(s):  
Courteney L. Benjamin ◽  
Elliot P. Norton ◽  
Benjamin M. Shirley ◽  
Rebecca R. Rogers ◽  
Tyler D. Williams ◽  
...  
Keyword(s):  
Reaction Time ◽  
Fluid Intake ◽  
Urine Specific Gravity ◽  
Hydration Status ◽  
Fluid Restriction ◽  
College Age ◽  
Urine Color ◽  
Before And After ◽  
Two Fluid ◽  
Over Time

The purpose of this study was to assess the effect of two fluid intake protocols on alertness and reaction time before and after fluid intake. Healthy college-age males (n = 12) followed two fluid intake protocols on separate occasions: (1) prescribed fluid (PF) and fluid restricted (FR). In PF, participants were instructed to consume 500 mL of fluid the night prior to and the morning of data collection. In FR, participants were instructed to refrain from the consumption of fluid for 12 h. To assess hydration status, urine specific gravity and urine color were measured. Participants perceived level of thirst and alertness were also recorded. Participants then completed visuomotor reaction time tests using the Dynavision LED board, using both a central visuomotor test and a peripheral visuomotor test (PVRT) prior to (1) and following (2) the ingestion of 100 mL of water. Participants displayed significantly improved PVRT in PF state as compared to FR (PF1 = 1.13 ± 0.16, PF2 = 1.04 ± 0.14; FR1 = 1.27 ± 0.27, FR2 = 1.18 ± 0.20; p = 0.038, ηp2 = 0.363). Both CVRT and PVRT improved over time, following the ingestion of 100 mL of fluid. Participants in the PF state were also significantly more alert than participants in the FR state (PF = 4 ± 2, FR = 5 ± 2; p = 0.019, ES = 0.839). Collectively, perceived alertness and PVRT were negatively impacted by FR.

scholarly journals Efficacy of an Educational Intervention on the Hydration of Indoor College Athletes

2020 ◽  
Author(s):  
Isabella S. Abbasi ◽  
Rebecca M. Lopez ◽  
Yi-Tzu Kuo ◽  
B. Sue Shapiro
Keyword(s):  
Educational Intervention ◽  
Fluid Intake ◽  
Female Athletes ◽  
Sweat Rate ◽  
Urine Specific Gravity ◽  
Hydration Status ◽  
Intervention Period ◽  
Post Intervention ◽  
Urine Color ◽  
Before And After

Context: Research focusing on improving hydration status and knowledge in indoor female athletes is limited. Previous research has demonstrated hydration education is an optimal tool for improving the hydration status of athletes. Objective: To assess hydration status and fluid intake of collegiate female indoor athletes before and after a one-time educational intervention. Design: Controlled field study Setting: Collegiate women's volleyball and basketball practices Participants: Twenty-five female collegiate volleyball and basketball athletes (21±1years; 173.5±8.7cm, 72.1±10.0kg) were assessed during six days of practices. Intervention(s): Participants' hydration status and habits were monitored for 3 practice days before undergoing a hydration educational intervention. Post-intervention, participants were observed for 3 more practice days. Main Outcome Measures: Change in body mass (BM), fluid consumed, urine specific gravity (USG), urine color (Ucol), and sweat rate were recorded for 6 practice days. Participants completed a hydration knowledge questionnaire (HAQ) before and after the intervention to assess changes. Results: Three-day mean USG and Ucol were considered euhydrated pre-practice (USG 1.015±0.006, Ucol 4±1) and remained euhydrated post-practice (USG 1.019±0.005, Ucol 5±2) during the pre-intervention period. Decreases in pre-practice Ucol (p<.01) and increases (p<.01) in hydration knowledge were found post-intervention. Basketball athletes had greater BM losses from pre- to post-practice compared to volleyball (p=.000). Significant increases were found overall when comparing pre- and post-practice measures of USG and Ucol in pre-intervention period (p=.000, p=.001) and post-intervention period (p=.001, p=.000). No correlation was found between hydration knowledge and physiological indices of hydration and fluid intake. Conclusions: Overall, female collegiate indoor athletes were hydrated and knowledgeable of hydration. Variability in findings indicates further research is needed with this sport; clinically, attention should be given to individualized needs of each athlete. More research is needed to determine if a one-time educational intervention may be an effective tool for improving overall hydration in this population.

scholarly journals Hydration Status and Fluid Needs of Division I Female Collegiate Athletes Exercising Indoors and Outdoors

Sports ◽  
2019 ◽  
Vol 7 (7) ◽  
pp. 155 ◽  
Author(s):  
Stephanie Olzinski ◽  
Joshua Beaumont ◽  
Meynard Toledo ◽  
Amber Yudell ◽  
Carol S. Johnston ◽  
...  
Keyword(s):  
Student Athletes ◽  
Fluid Intake ◽  
Sweat Rate ◽  
Collegiate Athletes ◽  
Urine Specific Gravity ◽  
Hydration Status ◽  
Before And After ◽  
Female Collegiate Athletes ◽  
Dry Conditions ◽  
C 30

The purpose was to determine differences in acute and chronic hydration status in female student-athletes (n = 40) practicing in moderate, dry conditions (17–25 °C, 30–57% humidity) indoors and outdoors. Body weight and urine samples were recorded before and after exercise as well as fluid intake. Sweat rates expressed as median and interquartile range did not differ, but fluid intake was significantly higher during indoor (0.64 [0.50, 0.83] L/h) vs. outdoor conditions (0.51 [0.43, 0.63] L/h), p = 0.001. Fluid intake compensated for indoor sweat rate but not outdoors. When exercising indoors, 49% of the student-athletes reported urine specific gravity (USG) values >1.020, and 24% of the day after morning samples were scored ≥4 on the color chart rating. The percentages increased to 58% and 31%, respectively, when exercising outdoors (p > 0.05). Thus, fluid intake was higher indoors vs. outdoors but sweat rate did not differ among athletes. Yet, chronic hydration status was impaired in more than 50% of the student-athletes with a discrepancy between USG scores and urine color scores identifying underhydration. This suggest that 24-h fluid intake should be taken into account and that hydration protocols may need to be tailored individually based on urine USG values. Practice location (indoors vs. outdoors) may further complicate hydration protocols.

scholarly journals Availability of a Flavored Beverage and Impact on Children’s Hydration Status, Sleep, and Mood

Nutrients ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1757
Author(s):  
Michael R. Szymanski ◽  
Gabrielle E. W. Giersch ◽  
Margaret C. Morrissey ◽  
Courteney L. Benjamin ◽  
Yasuki Sekiguchi ◽  
...  
Keyword(s):  
Sleep Quality ◽  
Quality Index ◽  
Pittsburgh Sleep Quality Index ◽  
Intervention Group ◽  
Urine Osmolality ◽  
Urine Specific Gravity ◽  
Hydration Status ◽  
Control Group ◽  
Profile Of Mood States ◽  
Urine Color

Euhydration remains a challenge in children due to lack of access and unpalatability of water and to other reasons. The purpose of this study was to determine if the availability/access to a beverage (Creative Roots®) influences hydration in children and, therefore, sleep quality and mood. Using a crossover investigation, 46 participants were randomly assigned to a control group (CON) or an intervention group and received Creative Roots® (INT) for two-week periods. We recorded daily first morning and afternoon urine color (Ucol), thirst perception, and bodyweight of the two groups. Participants reported to the lab once per week and provided first morning urine samples to assess Ucol, urine specific gravity (USG), and urine osmolality (Uosmo). Participants also completed the questionnaires Profile of Mood States-Adolescents (POMS-a) and Pittsburgh Sleep Quality Index (PSQI). Dependent t-tests were used to assess the effects of the intervention on hydration, mood, and sleep quality. Uosmo was greater and Ucol was darker in the control group (mean ± SD) [Uosmo: INT = 828 ± 177 mOsm·kg−1, CON = 879 ± 184 mOsm·kg−1, (p = 0.037], [Ucol:INT = 5 ± 1, CON = 5 ± 1, p = 0.024]. USG, POMS-a, and PSQI were not significant between the groups. At-home daily afternoon Ucol was darker in the control group [INT = 3 ± 1, CON = 3 ± 1, p = 0.022]. Access to Creative Roots® provides a small, potentially meaningful hydration benefit in children. However, children still demonstrated consistent mild dehydration based on Uosmo, despite consuming the beverage.

Rehydration with a Caffeinated Beverage during the Nonexercise Periods of 3 Consecutive Days of 2-a-Day Practices

2004 ◽  
Vol 14 (4) ◽  
pp. 419-429 ◽  
Author(s):  
Kelly A. Fiala ◽  
Douglas J. Casa ◽  
Melissa W. Roti
Keyword(s):  
Body Fat ◽  
Hydration Status ◽  
Double Blind ◽  
Psychological Measures ◽  
Mild Heat ◽  
Urine Color ◽  
Significant Difference ◽  
Before And After ◽  
Time Point

The purpose of this study was to assess the influence of rehydration with a caffeinated beverage during non exercise periods on hydration status throughout consecutive practices in the heat. Ten (7 women, 3 men) partially heat-acclimated athletes (age 24 ± ly, body fat 19.2 ± 2%, weight 68.4 ± 4.0 kg, height 170 ± 3 cm) completed 3 successive days of 2-a-day practices (2 h/ practice, 4 h/d) in mild heat (WBGT = 23 °C). The 2 trials (double-blind, random, cross-over design) included; 1) caffeine (CAF) rehydrated with Coca-Cola® and 2) caffeine-free (CF) rehydrated with Caffeine-Free Coca-Cola®. Urine and psychological measures were determined before and after each 2-h practice. A significant difference was found for urine color for the post-AM time point, F = 5.526, P = 0.031. No differences were found among other variables (P > 0.05). In summary, there is little evidence to suggest that the use of beverages containing caffeine during non exercise might hinder hydration status.

scholarly journals Effects of sex and menstrual cycle on volume-regulatory responses to 24-h fluid restriction

2020 ◽  
Vol 319 (5) ◽  
pp. R560-R565
Author(s):  
Gabrielle E. W. Giersch ◽  
Abigail T. Colburn ◽  
Margaret C. Morrissey ◽  
Cody R. Butler ◽  
Michaela L. Pruchnicki ◽  
...  
Keyword(s):  
Menstrual Cycle ◽  
Specific Gravity ◽  
Body Mass ◽  
Urine Osmolality ◽  
Reproductive Hormones ◽  
Urine Specific Gravity ◽  
Fluid Restriction ◽  
Urine Color ◽  
Fluid Regulation ◽  
The Impact

Reproductive hormones have significant nonreproductive physiological effects, including altering fluid regulation. Our purpose was to explore the impact of sex and menstrual cycle (MC) phase on volume-regulatory responses to 24-h fluid restriction (24-h FR). Participants (men: n = 12, 20 ± 2 yr; women: n = 10, 20 ± 1 yr) were assigned two randomized and counterbalanced fluid prescriptions [Euhy: euhydrated, urine specific gravity (USG) < 1.020; Dehy: 24-h FR, USG > 1.020]. Men completed both (MEuhy, MDehy), while women completed both in the late-follicular ( days 10–13; FDehy, FEuhy) and midluteal ( days 18–22; LDehy, LEuhy) phases. We measured body mass, plasma and urine osmolality (Posm, Uosm), urine specific gravity (USG), urine color (Ucol), and serum copeptin; 24-h FR yielded mild dehydration without influence of sex or MC ( P > 0.05). Copeptin increased in men following Dehy (pre: 8.2 ± 5.2, post: 15.8 ± 12.6, P = 0.04) but not in women (FDehy pre: 4.3 ± 1.6, post: 10.5 ± 6.9, P = 0.06; LDehy pre: 5.6 ± 3.5, post: 10.4 ± 6.2, P = 0.16). In FDehy, Posm increased following FR (pre: 288 ± 2, post: 292 ± 1, P = 0.03) but not in men (pre: 292 ± 3, post: 293 ± 2, P = 0.46). No MC differences were observed between body mass loss, Posm, Uosm, USG, and copeptin ( P > 0.05). These results suggest that volume-regulatory responses to 24-h FR were present in men but not in women, without apparent effects of the menstrual cycle.

scholarly journals Impact of Nutrient Intake on Hydration Biomarkers Following Exercise and Rehydration Using a Clustering-Based Approach

Nutrients ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 1276 ◽  
Author(s):  
Colleen X. Muñoz ◽  
Evan C. Johnson ◽  
Laura J. Kunces ◽  
Amy L. McKenzie ◽  
Michael Wininger ◽  
...  
Keyword(s):  
Body Mass ◽  
Nutrient Intake ◽  
Glycemic Load ◽  
Real Life ◽  
Plasma Osmolality ◽  
Urine Specific Gravity ◽  
Body Mass Change ◽  
Urine Color ◽  
Before And After ◽  
The Impact

We investigated the impact of nutrient intake on hydration biomarkers in cyclists before and after a 161 km ride, including one hour after a 650 mL water bolus consumed post-ride. To control for multicollinearity, we chose a clustering-based, machine learning statistical approach. Five hydration biomarkers (urine color, urine specific gravity, plasma osmolality, plasma copeptin, and body mass change) were configured as raw- and percent change. Linear regressions were used to test for associations between hydration markers and eight predictor terms derived from 19 nutrients merged into a reduced-dimensionality dataset through serial k-means clustering. Most predictor groups showed significant association with at least one hydration biomarker: (1) Glycemic Load + Carbohydrates + Sodium, (2) Protein + Fat + Zinc, (3) Magnesium + Calcium, (4) Pinitol, (5) Caffeine, (6) Fiber + Betaine, and (7) Water; potassium + three polyols, and mannitol + sorbitol showed no significant associations with any hydration biomarker. All five hydration biomarkers were associated with at least one nutrient predictor in at least one configuration. We conclude that in a real-life scenario, some nutrients may serve as mediators of body water, and urine-specific hydration biomarkers may be more responsive to nutrient intake than measures derived from plasma or body mass.

scholarly journals Racial and Sex Differences in 24 Hour Urinary Hydration Markers among Male and Female Emerging Adults: A Pilot Study

Nutrients ◽  
2020 ◽  
Vol 12 (4) ◽  
pp. 1068 ◽  
Author(s):  
William M. Adams ◽  
Derek J. Hevel ◽  
Jaclyn P. Maher ◽  
Jared T. McGuirt
Keyword(s):  
College Students ◽  
Emerging Adults ◽  
Fluid Intake ◽  
Urine Volume ◽  
Urine Osmolality ◽  
Urine Specific Gravity ◽  
Urine Color ◽  
Males And Females ◽  
Race Ethnicity ◽  
Hispanic White

The purpose of this study was to examine 24 h urinary hydration markers in non-Hispanic White (WH) and non-Hispanic Black (BL) males and females. Thirteen males (BL, n = 6; WH, n = 7) and nineteen females (BL, n = 16, WH, n = 3) (mean ± SD; age, 20 ± 4 y; height, 169.2 ± 12.2 cm; body mass, 71.3 ± 12.2 kg; body fat, 20.8 ± 9.7%) provided a 24 h urine sample across 7 (n = 13) or 3 (n = 19) consecutive days (148 d total) for assessment of urine volume (UVOL), urine osmolality (UOSM), urine specific gravity (USG), and urine color (UCOL). UVOL was significantly lower in BL (0.85 ± 0.43 L) compared to WH college students (2.03 ± 0.70 L) (p < 0.001). Measures of UOSM, USG, and UCOL, were significantly greater in BL (716 ± 263 mOsm∙kg−1, 1.020 ± 0.007, and 4.2 ± 1.4, respectively) compared to WH college students (473 ± 194 mOsm∙kg−1, 1.013 ± 0.006, 3.0 ± 1.2, and respectively) (p < 0.05). Differences in 24 h urinary hydration measures were not significantly different between males and females (p > 0.05) or between the interaction of sex and race/ethnicity (p > 0.05). Non-Hispanic Black men and women were inadequately hydrated compared to their non-Hispanic White counterparts. Our findings suggest that development of targeted strategies to improve habitual fluid intake and potentially overall health are needed.

Sweat rate, salt loss, and fluid intake during an intense on-ice practice in elite Canadian male junior hockey players

2008 ◽  
Vol 33 (2) ◽  
pp. 263-271 ◽  
Author(s):  
Matthew S. Palmer ◽  
Lawrence L. Spriet
Keyword(s):  
Mass Loss ◽  
Body Mass ◽  
Fluid Intake ◽  
Sweat Rate ◽  
Sodium Concentration ◽  
Urine Specific Gravity ◽  
Hydration Status ◽  
Body Mass Loss ◽  
Hockey Players ◽  
Sodium Loss

Previous research in many sports suggests that losing ~1%–2% body mass through sweating impairs athletic performance. Elite-level hockey involves high-intensity bursts of skating, arena temperatures are >10 °C, and players wear protective equipment, all of which promote sweating. This study examined the pre-practice hydration, on-ice fluid intake, and sweat and sodium losses of 44 candidates for Canada’s junior men’s hockey team (mean ± SE age, 18.4 ± 0.1 y; height, 184.8 ± 0.9 cm; mass, 89.9 ± 1.1 kg). Players were studied in groups of 10–12 during 4 intense 1 h practices (13.9 °C, 66% relative humidity) on 1 day. Hydration status was estimated by measuring urine specific gravity (USG). Sweat rate was calculated from body mass changes and fluid intake. Sweat sodium concentration ([Na]) was analyzed in forehead sweat patch samples and used with sweat rate to estimate sodium loss. Over 50% of players began practice mildly hypohydrated (USG > 1.020). Sweat rate during practice was 1.8 ± 0.1 L·h–1 and players replaced 58% (1.0 ± 0.1 L·h–1) of the sweat lost. Body mass loss averaged 0.8% ± 0.1%, but 1/3 of players lost more than 1%. Sweat [Na] was 54.2 ± 2.4 mmol·L–1 and sodium loss averaged 2.26 ± 0.17 g during practice. Players drank only water during practice and replaced no sodium. In summary, elite junior hockey players incurred large sweat and sodium losses during an intense practice, but 2/3 of players drank enough to minimize body mass loss. However, 1/3 of players lost more than 1% body mass despite ready access to fluid and numerous drinking opportunities from the coaches.

Effects of Three Oral Nutritional Supplements on Human Hydration Indices

2016 ◽  
Vol 26 (4) ◽  
pp. 356-362 ◽  
Author(s):  
Lindsay A. Ellis ◽  
Brandon A. Yates ◽  
Amy L. McKenzie ◽  
Colleen X. Muñoz ◽  
Douglas J. Casa ◽  
...  
Keyword(s):  
Assessment Tool ◽  
Urine Volume ◽  
Urine Osmolality ◽  
Ease Of Use ◽  
Urine Specific Gravity ◽  
Hydration Status ◽  
Urine Color ◽  
Significant Difference ◽  
Oral Nutritional Supplements ◽  
Double Blinded

Urine color (Ucol) as a hydration assessment tool provides practicality, ease of use, and correlates moderately to strongly with urine specific gravity (Usg) and urine osmolality (Uosm). Indicative of daily fluid turnover, along with solute and urochrome excretion in 24-hr samples, Ucol may also reflect dietary composition. Thus, the purpose of this investigation was to determine the efficacy of Ucol as a hydration status biomarker after nutritional supplementation with beetroot (880 mg), vitamin C (1000 mg), and riboflavin (200 mg). Twenty males (Mean ± SD; age, 21 ± 2 y; body mass, 82.12 ± 15.58 kg; height, 1.77 ± 0.06 m) consumed a standardized breakfast and collected all urine voids on one control day (CON) and 1 day after consuming a standardized breakfast and a randomized and double-blinded supplement (SUP) over 3 weeks. Participants replicated exercise and diet for one day before CON, and throughout CON and SUP. Ucol, Usg, Uosm, and urine volume were measured in all 24-hr samples, and Ucol and Usg were measured in all single samples. Ucol was a significant predictor of single sample Usg after all supplements (p < .05). Interestingly, 24-hr Ucol was not a significant predictor of 24-h Usg and Uosm after riboflavin supplementation (p = .20, p = .21). Further, there was a significant difference between CON and SUP 24-h Ucol only after riboflavin supplementation (p < .05). In conclusion, this investigation suggests that users of the UCC (urine color chart) should consider riboflavin supplementation when classifying hydration status and use a combination of urinary biomarkers (e.g., Usg and Ucol), both acutely and over 24 hr.

Energy Balance, Macronutrient Intake, and Hydration Status During a 1,230 km Ultra-Endurance Bike Marathon

2014 ◽  
Vol 24 (5) ◽  
pp. 497-506 ◽  
Author(s):  
Bjoern Geesmann ◽  
Joachim Mester ◽  
Karsten Koehler
Keyword(s):  
Energy Balance ◽  
Fluid Intake ◽  
Drinking Behavior ◽  
Urine Specific Gravity ◽  
Hydration Status ◽  
Macronutrient Intake ◽  
Gastrointestinal Discomfort ◽  
Individual Strategies ◽  
Ultra Endurance ◽  
Food And Fluid Intake

Athletes competing in ultra-endurance events are advised to meet energy requirements, to supply appropriate amounts of carbohydrates (CHO), and to be adequately hydrated before and during exercise. In practice, these recommendations may not be followed because of satiety, gastrointestinal discomfort, and fatigue. The purpose of the study was to assess energy balance, macronutrient intake and hydration status before and during a 1,230-km bike marathon. A group of 14 well-trained participants (VO2max: 63.2 ± 3.3 ml/kg/min) completed the marathon after 42:47 hr. Ad libitum food and fluid intake were monitored throughout the event. Energy expenditure (EE) was derived from power output and urine and blood markers were collected before the start, after 310, 618, and 921 km, after the finish, and 12 hr after the finish. Energy intake (EI; 19,749 ± 4,502 kcal) was lower than EE (25,303 ± 2,436 kcal) in 12 of 14 athletes. EI and CHO intake (average: 57.1 ± 17.7 g/hr) decreased significantly after km 618 (p < .05). Participants ingested on average 392 ± 85 ml/hr of fluid, but fluid intake decreased after km 618 (p < .05). Hydration appeared suboptimal before the start (urine specific gravity: 1.022 ± 0.010 g/ml) but did not change significantly throughout the event. The results show that participants failed to maintain in energy balance and that CHO and fluid intake dropped below recommended values during the second half of the bike marathon. Individual strategies to overcome satiety and fatigue may be necessary to improve eating and drinking behavior during prolonged ultra-endurance exercise.

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