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Capra ME, Stanyevic B, Giudice A, Monopoli D, Decarolis NM, Esposito S, Biasucci G. Nutrition for Children and Adolescents Who Practice Sport: A Narrative Review. Nutrients 2024; 16:2803. [PMID: 39203939 PMCID: PMC11357223 DOI: 10.3390/nu16162803] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2024] [Revised: 08/07/2024] [Accepted: 08/17/2024] [Indexed: 09/03/2024] Open
Abstract
At a developmental age, adequate physical activity is fundamental to overall health and well-being and preventing obesity. Moreover, establishing active behavior can help children and adolescents meet their growth and neurodevelopmental goals. Nutritional requirements vary according to intensity, frequency, and practiced physical activity or sport; therefore, pediatricians should give children and adolescents and their families adequate counseling, avoiding both nutrient deficiencies and excessive or inadequate supplement intake. The focus should be not only on sports performance but also on the child's well-being, growth, and neurodevelopment. Our narrative review aims to discuss the nutritional needs of children and adolescents who practice physical activity, non-competitive sports activity, and elite sports activity while also analyzing the role of food supplements and the risk of eating disorders within this category of subjects.
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Affiliation(s)
- Maria Elena Capra
- Pediatrics and Neonatology Unit, Guglielmo da Saliceto Hospital, 29121 Piacenza, Italy; (M.E.C.); (G.B.)
| | - Brigida Stanyevic
- Pediatric Clinic, Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy
| | - Antonella Giudice
- Pediatric Clinic, Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy
| | - Delia Monopoli
- Pediatric Clinic, Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy
| | - Nicola Mattia Decarolis
- Pediatric Clinic, Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy
| | - Susanna Esposito
- Pediatric Clinic, Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy
| | - Giacomo Biasucci
- Pediatrics and Neonatology Unit, Guglielmo da Saliceto Hospital, 29121 Piacenza, Italy; (M.E.C.); (G.B.)
- Department of Medicine and Surgery, University of Parma, 43126 Parma, Italy
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Nowaczyk PM, Adamczewski J, Durkalec-Michalski K. Practical Application and Methodological Considerations on the Basics of Sports Nutrition in Basketball: A Comprehensive Systematic Review of Observational and Interventional Studies. Nutrients 2023; 15:4484. [PMID: 37892559 PMCID: PMC10610293 DOI: 10.3390/nu15204484] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2023] [Revised: 10/14/2023] [Accepted: 10/17/2023] [Indexed: 10/29/2023] Open
Abstract
The current systematic review (PROSPERO registration no. CRD42022334707) of observational (OS) and interventional studies (IS) aimed at evaluating the state of scientific knowledge on the basics of sports nutrition, framing discipline-specific dietary recommendations, and indicating potential directions for future studies in various age, experience level, and able-bodied abilities groups of basketball players (BP). A systematic search of PubMed, SPORTDiscus, and Web of Science ended on 20 December 2022. Records were excluded if reporting studies on animals, sport disciplines other than basketball, or supplementation protocols other than those related to macronutrients and hydration manipulations. Risk of bias (RoB) was evaluated using Cochrane RoB_2 tools, 'JBI checklist for prevalence studies', and 'Quality assessment tool for before-after (pre-post) studies with no control group'. The relevant data was synthesized in tables and a narrative review was performed. Seventy-two records were included (2581 participants): 63 were on able-bodied BP (2433 participants) and 9 on para-athlete players (148 participants); 45 records were OS and 27 IS. The review disclosed widespread poor nutritional habits and knowledge and shortages in applying adequate nutritional and hydration practices in BP. Moreover, the systematic review revealed the lack of a sufficient number of investigations delivering reliable proof for framing discipline-specific and evidence-based recommendations on the basics of sports nutrition in basketball.
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Affiliation(s)
- Paulina M. Nowaczyk
- Department of Sports Dietetics, Poznań University of Physical Education, 61-871 Poznań, Poland;
| | - Jakub Adamczewski
- Department of Sports Dietetics, Poznań University of Physical Education, 61-871 Poznań, Poland;
| | - Krzysztof Durkalec-Michalski
- Department of Sports Dietetics, Poznań University of Physical Education, 61-871 Poznań, Poland;
- Sport Sciences–Biomedical Department, Charles University, 162 52 Prague, Czech Republic
- Centre for Sport Research, Deakin University, Burwood, VIC 3125, Australia
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3
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Rastmanesh R. Inadequate Hydration Status of Test Subjects Can Affect Bioavailability Studies. ACS Pharmacol Transl Sci 2023; 6:1104-1106. [PMID: 37470021 PMCID: PMC10353055 DOI: 10.1021/acsptsci.3c00089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Indexed: 07/21/2023]
Abstract
This Viewpoint identifies some of the pitfalls in the bioavailability of water-soluble drugs and introduces a novel bias we term the "hypohydration bias". We suggest that future bioavailability studies take some important neglected confounding factors into account, and we propose that, to avoid such a bias, some relevant variables such as serum and urine osmolality, dry weight adjustment, fluid balance, semi-nude body mass, saliva osmolality, saliva total protein concentration, and urine specific gravity should be controlled to increase the precision of the bioavailability measurements. We suggest that a new definition of hydration status is needed, and that systematic protocols of bioavailability studies should be revisited.
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Affiliation(s)
- Reza Rastmanesh
- American
Physical Society, College Park, Maryland 20740, USA
- The
Nutrition Society, London W6 7NJ, U.K.
- Independent
researcher, #6, Physicians
Building, Sarshar Alley, Vali-Asr, Tajrish, Tehran 1961835555, Iran
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Francisco R, Jesus F, Nunes CL, Cioffi I, Alvim M, Mendonca GV, Lukaski H, Sardinha LB, Silva AM. Athletes with different habitual fluid intakes differ in hydration status but not in body water compartments. Scand J Med Sci Sports 2023; 33:1072-1078. [PMID: 36951582 DOI: 10.1111/sms.14355] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2022] [Revised: 02/09/2023] [Accepted: 03/20/2023] [Indexed: 03/24/2023]
Abstract
Physiological differences have been reported between individuals who have habitual low (LOW) and high (HIGH) water intake (WI). The aims of this study were to explore body water compartments, hydration status, and fat-free mass (FFM) hydration of elite athletes exposed to different habitual WI. A total of 68 athletes (20.6 ± 5.3 years, 23 females) participated in this observational cross-sectional study. Total WI was assessed by seven-day food diaries and through WI, athletes were categorized as HIGH (n = 28, WI≥40.0 mL/kg/d) and LOW (n = 40, WI≤35.0 mL/kg/d). Total body water (TBW) and extracellular water (ECW) were determined by dilution techniques and intracellular water (ICW) as TBW-ECW. Hydration status was assessed by urine-specific gravity (USG) using a refractometer. Fat (FM) and FFM were assessed by dual-energy X-ray absorptiometry (DXA). The FFM hydration was calculated by TBW/FFM. The USG was statistically different between groups for females (LOW: 1.024 ± 0.003; HIGH: 1.015 ± 0.006; p = 0.005) and males (LOW: 1.024 ± 0.002; HIGH: 1.018 ± 0.005; p < 0.001). No differences between groups were detected in body water compartments and FFM hydration in both sexes (p > 0.05). Multiple regression showed that WI remains a predictor of USG regardless of FFM, age, and sex (β = -0.0004, p < 0.01). We concluded that LOW athletes were classified as dehydrated through USG although their water compartments were not different from HIGH athletes. These results suggest that LOW athletes may expectedly maintain the body water compartments' homeostasis through endocrine mechanisms. Interventions should be taken to encourage athletes to have sufficient WI to maintain optimal hydration.
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Affiliation(s)
- Rúben Francisco
- Exercise and Health Laboratory, CIPER, Faculdade Motricidade Humana, Universidade de Lisboa, Lisbon, Portugal
| | - Filipe Jesus
- Exercise and Health Laboratory, CIPER, Faculdade Motricidade Humana, Universidade de Lisboa, Lisbon, Portugal
| | - Catarina L Nunes
- Exercise and Health Laboratory, CIPER, Faculdade Motricidade Humana, Universidade de Lisboa, Lisbon, Portugal
| | - Iolanda Cioffi
- Department of Clinical Medicine and Surgery, Federico II University Hospital, Naples, Italy
| | - Marta Alvim
- National Institute of Health Doutor Ricardo Jorge, Lisbon, Portugal
| | - Goncalo V Mendonca
- Neuromuscular Research Lab, CIPER, Faculdade Motricidade Humana, Universidade de Lisboa, Lisbon, Portugal
| | - Henry Lukaski
- Department of Kinesiology and Public Health Education, Hyslop Sports Center, University of North Dakota, Grand Forks, North Dakota, USA
| | - Luís B Sardinha
- Exercise and Health Laboratory, CIPER, Faculdade Motricidade Humana, Universidade de Lisboa, Lisbon, Portugal
| | - Analiza M Silva
- Exercise and Health Laboratory, CIPER, Faculdade Motricidade Humana, Universidade de Lisboa, Lisbon, Portugal
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Chryssanthopoulos C, Dallas G, Arnaoutis G, Ragkousi EC, Kapodistria G, Lambropoulos I, Papassotiriou I, Philippou A, Maridaki M, Theos A. Young Artistic Gymnasts Drink Ad Libitum Only Half of Their Fluid Lost during Training, but More Fluid Intake Does Not Influence Performance. Nutrients 2023; 15:2667. [PMID: 37375571 DOI: 10.3390/nu15122667] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 06/06/2023] [Accepted: 06/06/2023] [Indexed: 06/29/2023] Open
Abstract
To examine the effect of the fluid balance on and performance in young artistic gymnasts during training under ad libitum and prescribed fluid intake conditions, eleven males (12.3 ± 2.6 years, mean ± SD) performed two 3 h identical training sessions. Participants ingested, in a random order, water equivalent to either 50% (LV) or 150% (HV) of their fluid loss. After the 3 h training, the gymnasts performed program routines on three apparatuses. The pre-exercise urine specific gravity (USG) was similar between conditions (LV: 1.018 ± 0.007 vs. HV: 1.015 ± 0.007; p = 0.09), while the post-exercise USG was lower in the HV condition (LV: 1.017 ± 0.006 vs. HV: 1.002 ± 0.003; p < 0.001). Fluid loss corresponding to percentage of body mass was higher in the LV condition (1.2 ± 0.5%) compared to the HV condition (0.4 ± 0.8%) (p = 0.02); however, the sums of the score performances were not different (LV: 26.17 ± 2.04 vs. HV: 26.05 ± 2.00; p = 0.57). Ingesting fluid equivalent to about 50% of the fluid lost, which was the amount that was drunk ad libitum during training, maintained short-term hydration levels and avoided excessive dehydration in artistic preadolescent and adolescent gymnasts. A higher amount of fluid, equivalent to about 1.5 times the fluid loss, did not provide an additional performance benefit.
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Affiliation(s)
- Costas Chryssanthopoulos
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, 17237 Athens, Greece
| | - Georgios Dallas
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, 17237 Athens, Greece
| | - Giannis Arnaoutis
- School of Health Science and Education, Department of Nutrition and Dietetics, Harokopio University, 17671 Athens, Greece
| | - Eirini Charikleia Ragkousi
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, 17237 Athens, Greece
| | - Georgia Kapodistria
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, 17237 Athens, Greece
| | | | - Ionas Papassotiriou
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, 17237 Athens, Greece
| | - Anastassios Philippou
- Department of Physiology, Medical School, National and Kapodistrian University of Athens, 11527 Athens, Greece
| | - Maria Maridaki
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, 17237 Athens, Greece
| | - Apostolos Theos
- Section of Sports Medicine, Department of Community Medicine & Rehabilitation, Umeå University, 901 87 Umeå, Sweden
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Turner O, Mitchell N, Ruddock A, Purvis A, Ranchordas MK. Fluid Balance, Sodium Losses and Hydration Practices of Elite Squash Players during Training. Nutrients 2023; 15:nu15071749. [PMID: 37049589 PMCID: PMC10096645 DOI: 10.3390/nu15071749] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2023] [Revised: 03/30/2023] [Accepted: 04/01/2023] [Indexed: 04/07/2023] Open
Abstract
Elite squash players are reported to train indoors at high volumes and intensities throughout a microcycle. This may increase hydration demands, with hypohydration potentially impairing many key performance indicators which characterise elite squash performance. Consequently, the main aim of this study was to quantify the sweat rates and sweat [Na+] of elite squash players throughout a training session, alongside their hydration practices. Fourteen (males = seven; females = seven) elite or world class squash player’s fluid balance, sweat [Na+] and hydration practices were calculated throughout a training session in moderate environmental conditions (20 ± 0.4 °C; 40.6 ± 1% RH). Rehydration practices were also quantified post-session until the players’ next training session, with some training the same day and some training the following day. Players had a mean fluid balance of −1.22 ± 1.22% throughout the session. Players had a mean sweat rate of 1.11 ± 0.56 L·h−1, with there being a significant difference between male and female players (p < 0.05), and a mean sweat (Na+) of 46 ± 12 mmol·L−1. Players training the following day were able to replace fluid and sodium losses, whereas players training again on the same day were not. These data suggest the variability in players hydration demands and highlight the need to individualise hydration strategies, as well as training prescription, to ensure players with high hydration demands have ample time to optimally rehydrate.
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Affiliation(s)
- Ollie Turner
- Academy of Sport & Physical Activity, Sheffield Hallam University, Sheffield S10 2BP, UK
- English Institute of Sport, Manchester M11 3BS, UK
| | | | - Alan Ruddock
- Academy of Sport & Physical Activity, Sheffield Hallam University, Sheffield S10 2BP, UK
| | - Alison Purvis
- Academy of Sport & Physical Activity, Sheffield Hallam University, Sheffield S10 2BP, UK
| | - Mayur K. Ranchordas
- Academy of Sport & Physical Activity, Sheffield Hallam University, Sheffield S10 2BP, UK
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Rivera-Brown AM, Correa JJ, Micheo WF. Return-to-Competition Progression After Exertional Heat Stroke in an Adolescent Runner: A Case Report. J Athl Train 2023; 58:349-354. [PMID: 35622950 PMCID: PMC11215635 DOI: 10.4085/1062-6050-0583.21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A 14-year-old runner indigenous to the tropics collapsed during his first 10-km race in a hot and humid climate. Dizziness, stumbling, and loss of consciousness were symptoms of exertional heat stroke. Two days postcollapse, blood tests revealed elevated hepatic transaminases consistent with hepatic injury. We discuss the return-to-competition progression, which included a gradual increase in exercise duration, initially in a cool and then in a tropical climate, and 2 field-based (wet-bulb globe temperature > 29.0°C) running evaluations that simulated the environmental conditions and training intensity the athlete would encounter in his sport. The thermoregulatory results guided the training progression, his tolerance to running in the heat improved, blood values normalized, and he was cleared to compete in a tropical climate. This exploration case report presents a novel field-based protocol that replicates the physiological demands of training in the tropics to evaluate thermoregulatory responses during exercise-heat stress in young runners after exertional heat stroke to facilitate a safe return to competition.
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Affiliation(s)
- Anita M. Rivera-Brown
- Department of Physical Medicine, Rehabilitation and Sports Medicine, Center for Sports Health and Exercise Sciences, San Juan
- Department of Physiology, University of Puerto Rico, School of Medicine, San Juan
| | - José J. Correa
- Department of Physical Medicine, Rehabilitation and Sports Medicine, Center for Sports Health and Exercise Sciences, San Juan
| | - William F. Micheo
- Department of Physical Medicine, Rehabilitation and Sports Medicine, Center for Sports Health and Exercise Sciences, San Juan
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Abstract
Optimal hydration is required for all physiologic functions and cognition. Children, especially younger ones, are particularly susceptible to dehydration, given their physiological specificities, in particular, their renal immaturity and relatively large skin surface in early life, but also their dependence on adults and their greater propensity to develop digestive diseases leading to fluid losses. Mild dehydration consequences are dominated by their impact on cognitive functions, whereas more severe dehydration may endanger the health outcome. Studies on this subject in children are scarce; in particular, the long-term consequence on renal function remains questionable. This review considers how children's water intake including fluid intake and water content of food, are worrying. The findings show that, worldwide, most children do not meet adequate water intake recommendations. The main problems likely to explain insufficient water intake are access to safe water, availability of drinking water at school, and healthy-hydration education, which are all points that need to be improved within health policy.
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Affiliation(s)
- Jean-Pierre Chouraqui
- Paediatric Nutrition and Gastroenterology, Division of Pediatrics, Woman, Mother and Child Department, Pediatric Nutrition and Gastroenterology Unit, University Hospital of Lausanne (CHUV), Lausanne, Switzerland
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A questionnaire study on the knowledge, attitudes, and practices of fluid replacement and urination among Chinese elite athletes. PLoS One 2022; 17:e0275685. [PMID: 36223380 PMCID: PMC9555643 DOI: 10.1371/journal.pone.0275685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 09/21/2022] [Indexed: 11/17/2022] Open
Abstract
OBJECTIVE To evaluate the knowledge, attitudes and practices (KAP) of Chinese elite athletes about fluid replacement and urination. METHODS A cross-section study was carried out among Chinese national and national youth teams from March to April 2020, using a pretested questionnaire. The 42-questions questionnaire was designed to assess the KAP regarding fluid replacement and urination. The questionnaire included knowledge of fluid replacement (KFR), attitudes of fluid replacement (AFR), knowledge of urination (KU), and attitudes of urination (AU), which were awarded 20 scoring points. Descriptive statistics, independent samples t-tests, one-way ANOVA, Pearson's correlation analysis, Multiple linear stepwise regression and Chi-square test were performed. RESULTS A total of 779 valid questionnaires were collected and the effective rate is 98.4%. We finally conducted an assessment of 646 questionnaires of elite athletes. The mean score for KFR, AFR, KU, and AU was 2.8±1.3, 2.3±0.6, 3.0±1.5, and 2.1±0.8, respectively, with higher scores indicating positive hydration knowledge and attitudes. KFR and AFR scores of winter sports athletes were higher than those of summer sports athletes(P<0.05). Athletes who had lower athletic grades and training years had a worse KFR(P<0.05). Only 31.0% athletes knew that rehydration should be carried out before, during, and after training, which was scarcer among women, lower-athletic grades athletes, or athletes with lower training years (P<0.05). Male athletes had a worse KU but a better AU than female athletes(P<0.05). And athletes who were international-class athletic grades had the highest KU scores(P<0.05). The athletic grades and sport events were the main factors influencing the total scores of knowledge and attitudes (P<0.05, 95% CI -0.789--0.168,95% CI 0.025-1.040). Most of athletes tend to get hydration knowledge from internet. In practices, thirst is the main reason for rehydration (77.9%). The percentages of athletes with normal urine color (42.0%), frequency (75.0%,) and volume (20.0%) were low. CONCLUSIONS These findings indicate that Chinese elite athletes did not have sufficient KAP on fluid replacement and urination, more marked in the individuals who were summer sport events, the lower athletic grades and in lower training years. It is recommended that education should be provided in the early stages of professional training for athletes.
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Evaluation of Water Intake in Spanish Adolescent Soccer Players during a Competition. J Hum Kinet 2022; 83:59-66. [PMID: 36157942 PMCID: PMC9465763 DOI: 10.2478/hukin-2022-0051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An optimal state of hydration is essential to maintaining health. The objective of this cross-sectional study was to evaluate the water intake of adolescents aged 12 to 16 years and their hydration level during an official soccer match. Three hundred and six players participated in the study (N = 306). Their water intake was recorded and the level of hydration was evaluated using the density of urine as an indicator. Weight measurements were made before and after the match. Water intake control, urine collection and analysis, and the recording of minutes played were carried out after the match. The average weight loss was 746.2 g (SD: 474.07; p < 0.001), with 36.5% with less than 1% loss and 23.3% with more than 2% loss. The mean volume of water ingested was 229.35 ml (SD: 211.11) and a significant correlation was observed between minutes of activity (ρ-value = 0.206; p < 0.001), environmental humidity (ρ-value = - 0.281; p < 0.001), and temperature (ρ-value = 0.200; p < 0.001). The sweat rate was 0.69 l/h (SD: 0.56) and it was significantly associated with playing time (ρ-value = -0.276; p < 0.001). The mean urine density was 1.019 (SD: 0.007), with 64.9% of youth athletes showing dehydration (≥ 1.020). An association was observed between dehydration and activity time (U- value = 4.124; p < 0.001). Approximately 10% of the participants stated that they had not drunk any water during the match. In conclusion, it is necessary to establish individual hydration guidelines based on personal, environmental and activity-related factors, as well as establish a minimum volume of fluids to consume.
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Attitudes and Opinions of Parents towards Water-Only Drink Policy at Junior Triathlon Events. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:ijerph19148529. [PMID: 35886378 PMCID: PMC9324034 DOI: 10.3390/ijerph19148529] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2022] [Revised: 07/10/2022] [Accepted: 07/11/2022] [Indexed: 02/01/2023]
Abstract
Rates of childhood obesity within Australia continue to rise, with consumption of sugar-sweetened beverages one contributing factor. Community sport provides an opportunity to implement policies promoting water as the beverage of choice. However, the attitudes of parents toward a water-only policy are not known. This cross-sectional study aimed to investigate parents’ opinions towards beverage consumption and a water-only policy. Data were collected from participants (n = 159) using an investigator-designed questionnaire, administered using iPads, at a junior Triathlon Victoria event. Water was the most popular beverage provided before (75%), during (85%) and after (61%) sport. Parents were more likely to provide sports drinks to children older than 14 years (27%). Three-quarters (77%) of parents reported having received no information regarding hydration requirements. Parents rated the importance of hydration prior to, during and after a triathlon as high (9.08 ± 1.2, 8.76 ± 1.3 and 9.30 ± 0.4 out of 10, respectively). Parents were supportive of a water-only policy at all junior triathlon events and all junior sporting events (7.94 ± 1.3 and 7.86 ± 1.9, respectively). There was less support for a water-only policy for adult triathlons (6.40 ± 3.1). A water-only drink policy at junior sport is viewed positively by parents. This warrants further research and policy development to facilitate behaviour change.
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Prevalence of Dehydration and the Relationship with Fluid Intake and Self‐Assessment of Hydration Status in Czech First League Soccer Players. J Hum Kinet 2022; 82:101-110. [PMID: 36157002 PMCID: PMC9465733 DOI: 10.2478/hukin-2022-0035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
The objective of this cross-sectional study was to evaluate the hydration status of Czech First League soccer players, and to compare the reported fluid intake, perceived fluid intake and thirst sensation of euhydrated (EU) and dehydrated (DE) players. The study involved 124 Czech male professional soccer players (age 25.2±5.0 years) participating in annual winter, pre-season laboratory testing. Hydration status was assessed based on urine specific gravity (USG), euhydration was set at USG≤1.020. Fluid intake and thirst perception were evaluated by a questionnaire. The sample mean for USG was 1.021±0.008, 56% of players were dehydrated. Reported daily fluid intake was significantly (p<0.001, d=0.95, large effect) higher in EU compared to DE players. Daily fluid intake negatively correlated with USG (rS=-0.46, p<0.001, medium effect). The fluid intake perception score was significantly (p=0.005, d=0.54, medium effect) better in EU compared to DE players. Reported intake perception scores negatively correlated with USG (rS=-0.32, p<0.001, medium effect). However, there was no correlation (rS=-0.09, p=0.34, trivial effect) between thirst perception scores and USG. Thirst perception scores were not significantly different between EU and DE players (p=0.35, d=0.18, trivial effect). Our results indicated that self-assessment of both daily fluid intake and perceived fluid intake matched with objective hydration status, while self-assessment of thirst perception was not an appropriate indicator of hydration status in elite soccer players.
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Lopez RM, Lund DC, Tritsch AJ, Liebl V. Relationship Between Pre- and Post-exercise Body Mass Changes and Pre-exercise Urine Color in Female Athletes. Front Sports Act Living 2022; 4:791699. [PMID: 35392595 PMCID: PMC8980779 DOI: 10.3389/fspor.2022.791699] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 02/15/2022] [Indexed: 11/13/2022] Open
Abstract
Although studies use body mass changes or urine color to measure hydration status, the purpose of this study was to examine the relationship between pre-practice urine color and exercise body mass changes in female tackle football players. Twenty-six female American football players (Age: 29.9 ± 7.3 years; Height: 165.2 ± 2.6 cm; Weight: 83.8 ± 24.4 kg) volunteered. Fluid consumptions (FC) was measured during tackle football practices, while urine color (Ucol), and percent body mass loss (%BML) were taken before and after practices. Subjects were grouped by %BML: lost mass (LM), gained mass (GM), or no change (NC). A one-way ANOVA compared groups on Ucol and FC. There were differences across groups for pre-practice Ucol (P < 0.01) and FC (P < 0.01). GM had a higher pre-practice Ucol than LM (P < 0.01) and NC (P < 0.05) and consumed more fluid than LM (P < 0.01) and NC (P < 0.05). A stepwise linear regression examined the extent that Ucol and FC were related to %BML. When predicting BML, FC accounted for 45% of variance (P < 0.01). The addition of pre-practice Ucol increased predicted variance explained (R2 change= 2.5%, P = 0032). Subjects who gained mass during practice arrived with elevated urine color (Ucol 5 ± 2), while those who lost mass arrived with pale urine color (Ucol 3 ± 2). Findings indicate those who arrived with an elevated urine color attempted to improve hydration status by consuming more fluid and gaining body mass during exercise.
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14
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Wardenaar F, Armistead S, Boeckman K, Butterick B, Youssefi D, Thompsett D, Vento K. Validity of Urine Color Scoring Using Different Light Conditions and Scoring Techniques to Assess Urine Concentration. J Athl Train 2022; 57:191-198. [PMID: 35201303 PMCID: PMC8876881 DOI: 10.4085/1062-6050-0389.21] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
CONTEXT Urine color (Uc) is used to asses urine concentration when laboratory techniques are not feasible. OBJECTIVE To compare the accuracy of Uc scoring using 4 light conditions and 2 scoring techniques with a 7-color Uc chart. Additionally, to assess the results' generalizability, a subsample was compared with scores obtained from fresh samples. DESIGN Descriptive laboratory study. SAMPLES A total of 178 previously frozen urine samples were scored, and 78 samples were compared with their own fresh outcomes. MAIN OUTCOME MEASURE(S) Urine color and accuracy for classifying urine samples were calculated using receiver operating characteristics analysis, allowing us to compare the diagnostic capacity against a 1.020 urine specific gravity cutoff and defining optimal Uc cutoff value. RESULTS Urine color was different among light conditions (P < .01), with the highest accuracy (80.3%) of correct classifications of low or high urine concentrations occurring at the brightest light condition. Lower light intensity scored 1.5 to 2 shades darker on the 7-color Uc scale than bright conditions (P < .001), but no further practical differences in accuracy occurred between scoring techniques. Frozen was 0.5 to 1 shade darker than freshly measured Uc (P < .004), but the values were moderately correlated (r = 0.64). A Bland-Altman plot showed that reporting bias mainly affected darker Uc without affecting the diagnostic ability of the method. CONCLUSIONS Urine color scoring, accuracy, and Uc cutoff values were affected by lighting condition but not by scoring technique, with greater accuracy and a 1-shade-lower Uc cutoff value at the brightest light (ie, light-emitting diode flashlight).
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Affiliation(s)
| | - Scott Armistead
- College of Health Solutions, Arizona State University, Phoenix
| | - Kayla Boeckman
- College of Health Solutions, Arizona State University, Phoenix
| | | | - Darya Youssefi
- College of Health Solutions, Arizona State University, Phoenix
| | | | - Kaila Vento
- College of Health Solutions, Arizona State University, Phoenix
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15
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Hydration Status and Fluid Replacement Strategies of High-Performance Adolescent Athletes: An Application of Machine Learning to Distinguish Hydration Characteristics. Nutrients 2021; 13:nu13114073. [PMID: 34836328 PMCID: PMC8625246 DOI: 10.3390/nu13114073] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 11/01/2021] [Accepted: 11/05/2021] [Indexed: 11/23/2022] Open
Abstract
There are limited data on the fluid balance characteristics and fluid replenishment behaviors of high-performance adolescent athletes. The heterogeneity of hydration status and practices of adolescent athletes warrant efficient approaches to individualizing hydration strategies. This study aimed to evaluate and characterize the hydration status and fluid balance characteristics of high-performance adolescent athletes and examine the differences in fluid consumption behaviors during training. In total, 105 high-performance adolescent athletes (male: 66, female: 39; age 14.1 ± 1.0 y) across 11 sports had their hydration status assessed on three separate occasions—upon rising and before a low and a high-intensity training session (pre-training). The results showed that 20–44% of athletes were identified as hypohydrated, with 21–44% and 15–34% of athletes commencing low- and high-intensity training in a hypohydrated state, respectively. Linear mixed model (LMM) analyses revealed that athletes who were hypohydrated consumed more fluid (F (1.183.85)) = 5.91, (p = 0.016). Additional K-means cluster analyses performed highlighted three clusters: “Heavy sweaters with sufficient compensatory hydration habits,” “Heavy sweaters with insufficient compensatory hydration habits” and “Light sweaters with sufficient compensatory hydration habits”. Our results highlight that high-performance adolescent athletes with ad libitum drinking have compensatory mechanisms to replenish fluids lost from training. The approach to distinguish athletes by hydration characteristics could assist practitioners in prioritizing future hydration intervention protocols.
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16
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Berry CW, Wolf ST, Cottle RM, Kenney WL. Hydration Is More Important Than Exogenous Carbohydrate Intake During Push-to-the-Finish Cycle Exercise in the Heat. Front Sports Act Living 2021; 3:742710. [PMID: 34746777 PMCID: PMC8568039 DOI: 10.3389/fspor.2021.742710] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2021] [Accepted: 09/23/2021] [Indexed: 11/13/2022] Open
Abstract
Dehydration ≥2% loss of body mass is associated with reductions in performance capacity, and carbohydrate (CHO)-electrolyte solutions (CES) are often recommended to prevent dehydration and provide a source of exogenous carbohydrate during exercise. It is also well established that performance capacity in the heat is diminished compared to cooler conditions, a response attributable to greater cardiovascular strain caused by high skin and core temperatures. Because hydration status, environmental conditions, and carbohydrate availability interact to influence performance capacity, we sought to determine how these factors affect push-to-the-finish cycling performance. Ten young trained cyclists exercised at a moderate intensity (2.5 W·kg-1) in a hot-dry condition [40°C, 20% relative humidity (RH)] until dehydration of ~2% body mass. Subjects then consumed either no fluid (NF) or enough fluid (water, WAT; Gatorade®, GAT; or GoodSport™, GS) to replace 75% of lost body mass over 30 min. After a 30-min light-intensity warm-up (1.5 W·kg-1) in a 35°C, 20% RH environment, subjects then completed a 120-kJ time trial (TT). TT time-to-completion, absolute power, and relative power were significantly improved in WAT (535 ± 214 s, 259 ± 99 W, 3.3 ± 0.9 W·kg-1), GAT (539 ± 226 s, 260 ± 110 W, 3.3 ± 1.0 W·kg-1), and GS (534 ± 238 s, 262 ± 105 W, 3.4 ± 1.0 W·kg-1) compared to NF (631 ± 310 s, 229 ± 96 W, 3.0 ± 0.9 W·kg-1) all (p < 0.01) with no differences between WAT, GAT, and GS, suggesting that hydration is more important than carbohydrate availability during exercise in the heat. A subset of four subjects returned to the laboratory to repeat the WAT, GAT, and GS treatments to determine if between-beverage differences in time-trial performance were evident with a longer TT in thermoneutral conditions. Following dehydration, the ambient conditions in the environmental chamber were reduced to 21°C and 20% RH and subjects completed a 250-kJ TT. All four subjects improved TT performance in the GS trial (919 ± 353 s, 300 ± 100 W, 3.61 ± 0.86 W·kg-1) compared to WAT (960 ± 376 s, 283 ± 91 W, 3.43 ± 0.83 W·kg-1), while three subjects improved TT performance in the GAT trial (946 ± 365 s, 293 ± 103 W, 3.60 ± 0.97 W·kg-1) compared to WAT, highlighting the importance of carbohydrate availability in cooler conditions as the length of a push-to-the-finish cycling task increases.
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Affiliation(s)
- Craig W Berry
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, United States
| | - S Tony Wolf
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, United States
| | - Rachel M Cottle
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, United States
| | - W Larry Kenney
- Noll Laboratory, Department of Kinesiology, The Pennsylvania State University, University Park, PA, United States.,Graduate Program in Physiology, The Pennsylvania State University, University Park, PA, United States
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17
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Godoy DF, Cadore EL, Feitosa WG, Correia RDA, Castro FADS. Oxygen Uptake of Wave Surfers and Complementary Parameters in Front Crawl and Surfing-Paddling Tests. J Strength Cond Res 2021; 35:2645-2650. [PMID: 31373983 DOI: 10.1519/jsc.0000000000003205] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
ABSTRACT Godoy, DF, Cadore, EL, Feitosa, WG, Correia, RdA, and Castro, FAdS. Oxygen uptake of wave surfers and complementary parameters in front crawl and surfing-paddling tests. J Strength Cond Res 35(9): 2645-2650, 2021-The aim of this study was to assess the reliability of the oxygen uptake and complementary parameters (heart rate [HR], blood lactate concentration, and rate of perceived exertion [RPE]) obtained from surfers swimming and paddling in a swimming pool. Fourteen recreational male surfers (37.7 ± 4.7 years old) were evaluated in (a) a maximal 300-m front crawl test and (b) paddling in a surfboard test, both at the same intensity and for the same duration. Peak oxygen uptake (V̇o2peak) during the tests (direct method), HR, blood lactate concentration (LA), and RPE were assessed. Two-way analysis of variance, a simple Student t test, effect size calculation, intraclass correlation coefficient, and limits of agreement were applied. In general, the tests presented similar results (except for HR), with low agreement, high intraclass correlation, and average to large effect sizes between swimming and paddling. The results suggest that surfers training in a swimming pool should not simply be swimming. Front crawl swimming and surf paddling are 2 distinct actions that should be practiced and tested on their own merits rather than assumed to be interchangeable.
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Affiliation(s)
- Daniel F Godoy
- Aquatic Sports Research Group, School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Eduardo L Cadore
- Strength Training Research Group, School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre, Brazil; and
| | - Wellington G Feitosa
- Aquatic Sports Research Group, School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre, Brazil.,Faculty of Physical Education, Cearà State University, Fortaleza, Brazil
| | - Ricardo de A Correia
- Aquatic Sports Research Group, School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
| | - Flávio A de S Castro
- Aquatic Sports Research Group, School of Physical Education, Physiotherapy and Dance, Federal University of Rio Grande do Sul, Porto Alegre, Brazil
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18
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Kontele I, Vassilakou T. Nutritional Risks among Adolescent Athletes with Disordered Eating. CHILDREN-BASEL 2021; 8:children8080715. [PMID: 34438606 PMCID: PMC8394476 DOI: 10.3390/children8080715] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 06/28/2021] [Revised: 08/16/2021] [Accepted: 08/19/2021] [Indexed: 01/29/2023]
Abstract
In their attempt to achieve the optimum weight or body shape for their activity, athletes frequently use harmful weight-control practices that may lead to the development of disordered eating or eating disorders. These practices are linked to several medical and mental consequences that may be more serious in adolescent athletes, as their bodies must meet both intensive growth demands and training requirements at the same time. Among other consequences, adolescent athletes may be at nutritional risk, due to their high nutrient needs and unhealthy eating behaviors. A literature review was conducted to examine the main nutritional risks and malnutrition issues faced by adolescent athletes that present disordered eating attitudes or eating disorders. Most studies refer to adult elite athletes, however research on adolescent athletes also indicates that the most common nutritional risks that may arise due to disordered eating include energy, macronutrient and micronutrient deficiencies, dehydration and electrolyte imbalances and changes in body composition that may lead to menstrual abnormalities, and decreased bone mass density. Educational programs and early detection of disordered eating and eating disorders are crucial to avoid the emergence and ensure timely management of nutrition-related problems in the vulnerable group of adolescent athletes.
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19
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Abbasi IS, Lopez RM, Kuo YT, Shapiro BS. Efficacy of an Educational Intervention for Improving the Hydration Status of Female Collegiate Indoor-Sport Athletes. J Athl Train 2021; 56:829-835. [PMID: 33237996 DOI: 10.4085/1062-6050-0495.19] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
CONTEXT Research focusing on improving hydration status and knowledge in female indoor-sport athletes is limited. Investigators have demonstrated that hydration education is an optimal tool for improving the hydration status of athletes. OBJECTIVE To assess the hydration status and fluid intake of collegiate female indoor-sport athletes before and after a 1-time educational intervention. DESIGN Controlled laboratory study. SETTING Collegiate women's volleyball and basketball practices. PATIENTS OR OTHER PARTICIPANTS A total of 25 female collegiate volleyball and basketball athletes (age = 21 ± 1 years, height = 173.5 ± 8.7 cm, weight = 72.1 ± 10.0 kg) were assessed during 6 days of practices. INTERVENTION(S) Participants' hydration status and habits were monitored for 3 practice days before they underwent a hydration educational intervention. Postintervention, participants were observed for 3 more practice days. MAIN OUTCOME MEASURE(S) Change in body mass, fluid consumed, urine specific gravity (Usg), urine color (Ucol), and sweat rate were recorded for 6 practice days. Participants completed a hydration-knowledge questionnaire before and after the intervention. RESULTS Three-day mean Usg and Ucol were considered euhydrated prepractice (Usg = 1.015 ± 0.006, Ucol = 4 ± 1) and remained euhydrated postpractice (Usg = 1.019 ± 0.005, Ucol = 5 ± 2) during the preintervention period. Decreased prepractice Ucol (P < .01) and increased hydration knowledge (P < .01) were present postintervention. Basketball athletes had greater body mass losses from prepractice to postpractice than did volleyball athletes (P < .001). Overall increases were evident when we compared prepractice and postpractice measures of Usg and Ucol in the preintervention (P < .001 and P = .001, respectively) and postintervention (P = .001 and P < .001) period, respectively. No correlation was found between hydration knowledge and physiological indices of hydration and fluid intake. CONCLUSIONS Overall, female collegiate indoor-sport athletes were hydrated and knowledgeable on hydration. However, our variable findings indicated that further research on these athletes is needed; clinically, attention should be given to the individual needs of each athlete. More examination will demonstrate whether a 1-time educational intervention may be an effective tool for improving hydration status in this population.
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Affiliation(s)
- Isabella S Abbasi
- Department of Orthopaedics and Sports Medicine, School of Physical Therapy and Rehabilitation Sciences, University of South Florida, Tampa
| | - Rebecca M Lopez
- Department of Orthopaedics and Sports Medicine, School of Physical Therapy and Rehabilitation Sciences, University of South Florida, Tampa
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20
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Yeargin S, Torres-McGehee TM, Emerson D, Koller J, Dickinson J. Hydration, Eating Attitudes and Behaviors in Age and Weight-Restricted Youth American Football Players. Nutrients 2021; 13:nu13082565. [PMID: 34444723 PMCID: PMC8401195 DOI: 10.3390/nu13082565] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Revised: 07/19/2021] [Accepted: 07/21/2021] [Indexed: 01/17/2023] Open
Abstract
There is a paucity of research examining hydration and nutrition behaviors in youth American football players. A potentially unique risk factor are league restrictions based on weight (WR) or age (AR). The purpose of this study was to examine hydration status between WR and AR leagues. The secondary purpose was to describe eating patterns in players. An observational cohort design with 63 youth football players (10 ± 1 yrs, 148.2 ± 9.4 cm, 44.9 ± 15.3 kg) was utilized. Independent variables were league (AR (n = 36); WR (n = 27)) and activity type (practice (PX = 8); game (GM = 3)). Dependent variables were hydration status (urine osmolality; percent change in body mass (%BM)), eating attitudes (Children’s Eating Attitude Test (ChEAT-26)) and self-reported frequency of meals. On average, players arrived activity mildly hypohydrated (830 ± 296 mOsm/kg) and %BM was minimal (−0.1 ± 0.7%) during events. Players consumed 2 ± 1 meals and 1 ± 1 snack before events. The ChEAT-26 survey reported 21.6% (n = 8) of players were at risk for abnormal eating attitudes. Among these players, eating binges, vomiting, excessive exercise and drastic weight loss were reported. Youth American football players arrived activity mildly hypohydrated and consumed enough fluid during activity to maintain euhydration. Abnormal eating attitudes and the use of unhealthy weight loss methods were reported by some youth American football players.
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Affiliation(s)
- Susan Yeargin
- Exercise Science Department, Arnold School of Public Health University of South Carolina, Columbia, SC 29208, USA;
- Correspondence:
| | - Toni M. Torres-McGehee
- Exercise Science Department, Arnold School of Public Health University of South Carolina, Columbia, SC 29208, USA;
| | - Dawn Emerson
- Department of Physical Therapy, Rehabilitation Sciences, and Athletic Training, School of Health Professions University of Kansas Medical Center, Kansas City, KS 66160, USA;
| | | | - John Dickinson
- Palmetto Health/USC Orthopedic Center, Columbia, SC 29203, USA;
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21
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Wiśniewski D, Śliwicka E, Malik J, Durkalec-Michalski K. Evaluation of Fluid Loss and Customary Fluid Intake among a Selected Group of Young Swimmers: A Preliminary Field Study. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18063205. [PMID: 33808826 PMCID: PMC8003718 DOI: 10.3390/ijerph18063205] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 03/15/2021] [Accepted: 03/16/2021] [Indexed: 11/26/2022]
Abstract
This study aimed to assess fluid loss (FL) and customary fluid intake (FI) during a training session, and the relationship between FL and total body water (TBW) content in a selected group of young swimmers. The study involved 17 (seven females, 10 males) individuals whose anthropometric and body composition analyses and FI during training units were carried out. The total average FI and total actual FL oscillated around 531 mL and −513 mL for the whole study group (469 mL and −284 mL for females, 574 mL and −674 mL for males). The dependent and independent sample t-tests, the Cohen’s d effect size and Pearson’s correlation coefficient were analysed. Significant differences were observed between pre-workout and post-workout body weights after training without FI in the whole group (66.5 kg vs. 66.0 kg, p < 0.001, d = 0.06), in females (61.2 kg vs. 60.9 kg, p = 0.015, d = 0.04) and males (70.3 kg vs. 69.6 kg, p < 0.001, d = 0.9). For the TBW content and fat-free mass (FFM) before and after training, significant differences were observed only in males (TBW: 43.8 L vs. 43.2 L, p = 0.002, d = 0.14; and 62.4% vs. 61.7%, p < 0.001, d = 0.36; FFM: 59.8 kg vs. 59.1 kg, p = 0.002, d = 0.12). Moreover, the relationship between the actual FL and TBW before training was observed in the whole (mL vs. %: r = −0.64, p = 0.006; mL vs. L: r = −0.84, p < 0.001) and the male group (mL vs. L: r = −0.73, p = 0.017). These results indicated FL in young swimmers during training and the relationship between FL and pre-training TBW content, which suggests that it is important to also pay special attention to effective hydration procedures before and during training in aquatic environments.
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Affiliation(s)
- Damian Wiśniewski
- Department of Sports Dietetics, Poznan University of Physical Education, 61-871 Poznań, Poland;
| | - Ewa Śliwicka
- Department of Physiology and Biochemistry, Poznan University of Physical Education, 61-871 Poznań, Poland;
| | - Jakub Malik
- Department of Physical Activity and Health Promotion Science, Poznan University of Physical Education, 61-871 Poznań, Poland;
| | - Krzysztof Durkalec-Michalski
- Department of Sports Dietetics, Poznan University of Physical Education, 61-871 Poznań, Poland;
- Department of Human Nutrition and Dietetics, Poznan University of Life Sciences, 61-871 Poznań, Poland
- Correspondence: ; Tel.: +48-61-835-52-87
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22
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Campbell EH, Irving R, McFarlane S, Dilworth L, Poudevigne M, Bailey J. Evidence that variations in pre-training hydration status are related to the frequency of endurance training in elite adolescent sprinters. J Sports Med Phys Fitness 2021; 61:1620-1628. [PMID: 33586933 DOI: 10.23736/s0022-4707.21.12025-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
BACKGROUND Although the effect of dehydration on performance is widely studied, limited data concerning the levels of risk training types pose to hydration status exists. This study sought to determine: (a) pre-training hydration status in adolescent sprinters relative to non-athletes, (b) changes in hydration markers across a season of adolescent sprinters relative to non-athletes, and (c) if frequency of training type explains unique variance in hydration. METHODS Hydration [via pre-training urine osmolality (UOsm) and thirst perception (TP)], daily water intake (TWI) [via 24-h food/fluid diaries] and frequencies of resistance, endurance and sprint training types (via training regime questionnaires) were assessed in 26 sprinters (age: 15.6±1.9 years) and 26 non-athletes (age: 16.0±1.6 years), during 4 mesocycles [general (T1) and specific (T2) preparation; pre-competitive (T3) and peaking (T4) phases], over 26 weeks. RESULTS Most athletes (62%-81%) and non-athletes (73%-92%) were underhydrated (UOsm>700 mOsmol/kg) pre-training across the season, despite a low TP. There were significant time (p =.042) and group (p =.006) effects, and a main group by time interaction for UOsm (p =.006) but not TP across the season, after controlling for TWI. Greater UOsm (in mOsmol/kg) were observed during T1 (906.3±250.1) and T2 (934.5±257.0) compared to T3 (852.1±268.8) and T4 (854.2±218.8). There was no significant change across the season for non-athletes. Frequencies of endurance training were positively associated with UOsm and explained unique variances across the season (R2 range from 7%-16%). CONCLUSIONS Underhydration is high in the adolescent population. Training type may be related to the variations in hydration throughout a season, which may help to inform hydration practices of sprint athletes.
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Affiliation(s)
- Eon H Campbell
- Biochemistry Section, Department of Basic Medical Sciences, The University of the West Indies, Mona, Jamaica -
| | - Rachael Irving
- Biochemistry Section, Department of Basic Medical Sciences, The University of the West Indies, Mona, Jamaica
| | - Shelly McFarlane
- Caribbean Institute for Health Research, The University of the West Indies at Mona, Mona, Jamaica
| | - Lowell Dilworth
- Department of Pathology, The University of the West Indies at Mona, Mona, Jamaica
| | - Melanie Poudevigne
- Health and Fitness Management, Clayton State University, Morrow, GA, USA
| | - Janel Bailey
- Biochemistry Section, Department of Basic Medical Sciences, The University of the West Indies, Mona, Jamaica
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23
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Martín-Payo R, Fernández-Álvarez MDM, Zabaleta-del-Olmo E, García-García R, González-Méndez X, Carrasco-Santos S. Feasibility Study of an Educational Intervention to Improve Water Intake in Adolescent Soccer Players: A Two-Arm, Non-Randomized Controlled Cluster Trial. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2021; 18:ijerph18031339. [PMID: 33540715 PMCID: PMC7908608 DOI: 10.3390/ijerph18031339] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Revised: 01/29/2021] [Accepted: 01/30/2021] [Indexed: 11/16/2022]
Abstract
This study aimed to assess the feasibility of an educational intervention on hydration behavior in adolescent soccer players. A pilot study of a two-arm, non-randomized controlled cluster trial was conducted. A total of 316 players aged 13-16 agreed to participate. The response variables were the players' participation in the intervention, their perception of the knowledge acquired, the usefulness and the overall assessment of the intervention. Hydration patterns and acquisition of knowledge on hydration behavior were also assessed. The intervention involved two elements: posters and a web app. A total of 259 adolescents completed the study (intervention group (IG) = 131; control group (CG) = 128). 80.6% of the players responded to the survey assessing the feasibility of the intervention. The mean number of correct answers regarding behavior was significantly higher in the IG (3.54; SD = 1.162) than in the CG (2.64; SD = 1.174) (p < 0.001). The water consumption pattern at all the clubs was ad libitum. Of the players, 10% did not drink any water at all during the game. In conclusion, this intervention has been shown to be feasible for implementation with adolescent soccer players. It suggests that hydration guidelines should be informed by personal factors and that ad libitum water consumption should be avoided.
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Affiliation(s)
- Rubén Martín-Payo
- Faculty of Medicine and Health Sciences, University of Oviedo, Campus del Cristo s/n, 33006 Oviedo, Spain;
- PRECAM Research Team, Health Research Institute of the Principality of Asturias, Avenida Roma s/n, 33011 Oviedo, Spain; (R.G.-G.); (X.G.-M.); (S.C.-S.)
| | - María del Mar Fernández-Álvarez
- Faculty of Medicine and Health Sciences, University of Oviedo, Campus del Cristo s/n, 33006 Oviedo, Spain;
- PRECAM Research Team, Health Research Institute of the Principality of Asturias, Avenida Roma s/n, 33011 Oviedo, Spain; (R.G.-G.); (X.G.-M.); (S.C.-S.)
- Correspondence:
| | - Edurne Zabaleta-del-Olmo
- Fundació Institut Universitari per a la recerca a l’Atenció Primària de Salut Jordi Gol i Gurina (IDIAPJGol), 08007 Barcelona, Spain;
- Gerència Territorial de Barcelona, Institut Català de la Salut, 08007 Barcelona, Spain
- Nursing Department, Nursing Faculty, Universitat de Girona, 17004 Girona, Spain
- Campus Bellaterra, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Rebeca García-García
- PRECAM Research Team, Health Research Institute of the Principality of Asturias, Avenida Roma s/n, 33011 Oviedo, Spain; (R.G.-G.); (X.G.-M.); (S.C.-S.)
- Hospital Universitario Central de Asturias, Avenida Roma s/n, 33011 Oviedo, Spain
| | - Xana González-Méndez
- PRECAM Research Team, Health Research Institute of the Principality of Asturias, Avenida Roma s/n, 33011 Oviedo, Spain; (R.G.-G.); (X.G.-M.); (S.C.-S.)
- Hospital Universitario San Agustín de Avilés, Camino de Heros 6, 33401 Avilés, Spain
| | - Sergio Carrasco-Santos
- PRECAM Research Team, Health Research Institute of the Principality of Asturias, Avenida Roma s/n, 33011 Oviedo, Spain; (R.G.-G.); (X.G.-M.); (S.C.-S.)
- Hospital Universitario San Agustín de Avilés, Camino de Heros 6, 33401 Avilés, Spain
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Hannon MP, Flueck JL, Gremeaux V, Place N, Kayser B, Donnelly C. Key Nutritional Considerations for Youth Winter Sports Athletes to Optimize Growth, Maturation and Sporting Development. Front Sports Act Living 2021; 3:599118. [PMID: 33585814 PMCID: PMC7873521 DOI: 10.3389/fspor.2021.599118] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 01/05/2021] [Indexed: 12/12/2022] Open
Abstract
Despite a wealth of sport nutrition guidelines for adult athletes, there are currently no nutrition guidelines for youth winter sports athletes. Whilst it may be pragmatic to apply nutrition guidelines for adult athletes to youth winter sports athletes, it is inappropriate. Due to a paucity of research on youth athletes, it is impossible to provide evidence-based guidelines for this population, so careful extrapolation from the theoretical and practical considerations that apply to other athletic groups is necessary. Youth winter sport athletes undergo rapid biological growth and maturation which influences their nutritional requirements. A varied and balanced diet that ensures sufficient energy availability for optimal growth and maturation as well as sporting performance is the cornerstone of youth athlete nutrition and should also allow for youth athletes to meet their micronutrient requirements. In some cases, micronutrient status (e.g., vitamin D and iron) should be monitored and optimized if appropriate by a medical professional. Dietary supplement use is prevalent amongst youth athletes, however is often unnecessary. Education of youth athletes, their parents and coaches on best nutritional practices as well as the risks associated with dietary supplements is vital for their long-term athletic development. Further research in youth winter sports athletes across different stages of growth and maturation competing in a variety of sports is urgently required in order to inform nutritional guidelines for this population.
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Affiliation(s)
- Marcus P. Hannon
- Research Institute for Sport and Exercise Sciences (RISES), Liverpool John Moores University, Liverpool, United Kingdom
| | | | - Vincent Gremeaux
- Swiss Olympic Medical Center, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland
- Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Nicolas Place
- Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Bengt Kayser
- Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
| | - Chris Donnelly
- Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland
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Evaluation of Pragmatic Methods to Rapidly Assess Habitual Beverage Intake and Hydration Status in U.S. Collegiate Athletes. Int J Sport Nutr Exerc Metab 2021; 31:115-124. [PMID: 33406482 DOI: 10.1123/ijsnem.2020-0125] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Revised: 09/26/2020] [Accepted: 10/11/2020] [Indexed: 11/18/2022]
Abstract
Fluid intake recommendations have been established for the athletic population in order to promote adequate hydration. The Beverage Intake Questionnaire (BEVQ-15) is a quick and reliable food frequency questionnaire that quantifies habitual beverage intake, which has been validated in children, adolescents, and adults. However, no validated beverage consumption questionnaire is available for collegiate athletes. Urine color (UC), while feasible for determining hydration status, has not been validated within a variety of collegiate athletes. The purpose of this investigation was to evaluate the comparative validity and reliability of pragmatic methods to rapidly assess BEVQ-15 and UC rating in U.S. Division I collegiate athletes. Student-athletes (n = 120; 54% females; age 19 ± 1 years) from two universities were recruited to complete three study sessions. At the first and third sessions, the participants completed the BEVQ-15 and provided a urine sample to determine UC and urinary specific gravity. All sessions included completion of a 24-hr dietary recall. Total fluid intake (fl oz) was 111 ± 107 and 108 ± 42 using the BEVQ-15 and the mean of three 24-hr dietary recalls, respectively, which was not different between methods (p > .05). There were moderate associations between the BEVQ-15 and dietary recall results for total beverage intake fl oz and kcal(r = .413 and r = 4.65; p ≤ .05, respectively). Strong associations were noted between both researcher-rated and participant-rated UC with urinary specific gravity measures (r = .675 and r = .884; p ≤ .05, respectively). Therefore, these rapid assessment methods demonstrated acceptable validity and may be used as practical methods to determine whether athletes are meeting their hydration recommendations.
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Tan B, Philipp M, Hill S, Che Muhamed AM, Mündel T. Pain Across the Menstrual Cycle: Considerations of Hydration. Front Physiol 2020; 11:585667. [PMID: 33132918 PMCID: PMC7578918 DOI: 10.3389/fphys.2020.585667] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Accepted: 09/16/2020] [Indexed: 11/20/2022] Open
Abstract
Chronic pain – pain that persists for more than 3 months – is a global health problem and is associated with tremendous social and economic cost. Yet, current pain treatments are often ineffective, as pain is complex and influenced by numerous factors. Hypohydration was recently shown to increase ratings of pain in men, but studies in this area are limited (n = 3). Moreover, whether hypohydration also affects pain in women has not been examined. In women, changes in the concentrations of reproductive hormones across menstrual phases may affect pain, as well as the regulation of body water. This indicates potential interactions between the menstrual phase and hypohydration on pain, but this hypothesis has yet to be tested. This review examined the literature concerning the effects of the menstrual phase and hypohydration on pain, to explore how these factors may interact to influence pain. Future research investigating the combined effects of hypohydration and menstrual phase on pain is warranted, as the findings could have important implications for the treatment of pain in women, interpretation of previous research and the design of future studies.
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Affiliation(s)
- Beverly Tan
- School of Sport, Exercise and Nutrition, Massey University, Palmerston North, New Zealand
| | - Michael Philipp
- School of Psychology, Massey University, Palmerston North, New Zealand
| | - Stephen Hill
- School of Psychology, Massey University, Palmerston North, New Zealand
| | | | - Toby Mündel
- School of Sport, Exercise and Nutrition, Massey University, Palmerston North, New Zealand
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Abed MEF, Deshayes TA, Claveau P, Jeker D, Thénault F, Goulet ED. Impact of Mild Hypohydration on 100 m Front Crawl Performance and Starting Block Peak Force Production in Competitive University-Level Swimmers. Sports (Basel) 2020; 8:sports8100133. [PMID: 33066345 PMCID: PMC7602092 DOI: 10.3390/sports8100133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2020] [Revised: 10/06/2020] [Accepted: 10/09/2020] [Indexed: 11/29/2022] Open
Abstract
Unstructured, ad libitum drinking may predispose some athletes to start exercise already slightly hypohydrated (decreased body water). The impact of pre-exercise mild hypohydration on subsequent swimming performance is still unknown. Hence, the goal of this study was to examine its effect on peak force production on the starting block and 100 m front crawl swimming performance in competitive university-level swimmers. At least one hour after having been passively exposed to heat where a body mass loss of 1.5% was induced or euhydration (normal body water) maintained, nine participants (age: 22 ± 2 years) underwent an assessment of their peak force production on the starting block and 100 m front crawl performance. One hour following hypohydration, rectal temperature had returned to baseline in each condition. Urine osmolality and specific gravity were higher (p < 0.05) with hypohydration than euhydration (995 ± 65 vs. 428 ± 345 mOsmol/kg; 1.027 ± 0.003 vs. 1.016 ± 0.007 g/mL) prior to exercise testing, as was perceived thirst. Swimming performance (p = 0.86) and peak force production (p = 0.72) on the starting block did not differ between the hypohydration and euhydrated condition (63.00 ± 4.26 vs. 63.09 ± 4.52 s; 1322 ± 236 vs. 1315 ± 230 N). The current results indicate that mild hypohydration, which may occur with ad libitum drinking, does not impede peak force production on the starting block and 100 m front crawl performance in university-level competitive swimmers. Planned drinking is not required prior to such an event.
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Affiliation(s)
- Mohamed El Fethi Abed
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (M.E.F.A.); (T.A.D.); (P.C.); (D.J.); (F.T.)
| | - Thomas A. Deshayes
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (M.E.F.A.); (T.A.D.); (P.C.); (D.J.); (F.T.)
- Research Centre on Aging, University of Sherbrooke, Sherbrooke, QC J1H 4C4, Canada
| | - Pascale Claveau
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (M.E.F.A.); (T.A.D.); (P.C.); (D.J.); (F.T.)
| | - David Jeker
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (M.E.F.A.); (T.A.D.); (P.C.); (D.J.); (F.T.)
| | - François Thénault
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (M.E.F.A.); (T.A.D.); (P.C.); (D.J.); (F.T.)
| | - Eric D.B. Goulet
- Faculty of Physical Activity Sciences, University of Sherbrooke, Sherbrooke, QC J1K 2R1, Canada; (M.E.F.A.); (T.A.D.); (P.C.); (D.J.); (F.T.)
- Research Centre on Aging, University of Sherbrooke, Sherbrooke, QC J1H 4C4, Canada
- Correspondence: ; Tel.: +1-819-821-8000 (ext. 62728)
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Kostelnik SB, Davy KP, Hedrick VE, Thomas DT, Davy BM. The Validity of Urine Color as a Hydration Biomarker within the General Adult Population and Athletes: A Systematic Review. J Am Coll Nutr 2020; 40:172-179. [PMID: 32330109 DOI: 10.1080/07315724.2020.1750073] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
Frequent monitoring of hydration status may help to avoid the adverse effects of dehydration. Other than urine color assessment, hydration assessment methods are largely impractical for the general population and athletes to implement on a routine basis. Despite its widespread use, the validity of urine color as an indicator of hydration status has not been systematically evaluated. The objective of this systematic review is to determine the validity of urine color evaluation as a hydration status assessment method in the general adult population, older adults, and athletes. Using the PRISMA guidelines, electronic databases were searched to identify original research articles of all study design types for inclusion. Of the 424 articles screened, 10 met inclusion criteria. Most studies compared urine color to either urinary specific gravity or urine osmolality, and reported significant associations (r) ranging from 0.40 to 0.93. Lower correlations were noted in studies of adults aged >60 years. Studies generally reported a high sensitivity of urine color as a diagnostic tool for detecting dehydration and supported the ability of this method to distinguish across categories of hydration status. Research is needed to determine if clinicians, patients, and clients can accurately utilize this method in clinical and real-world settings. Future research is also needed to extend these findings to other populations, such as children.Key teaching pointsInadequate hydration can lead to impairments in physical performance and cognitive function.Methods used to assess hydration status include plasma/serum osmolality, urinary specific gravity (USG), urine osmolality (Uosm), change in body weight, urine volume, and urine color.Urine color assessment is a practical method that is routinely used in clinical, athletic, and other settings. The validity of this method has not been systemically evaluated.Available research was limited to 10 articles.Validity of this method was generally supported; however, research has not investigated the validity of this method by clinicians, patients and clients.
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Affiliation(s)
- Samantha B Kostelnik
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, Virginia, USA
| | - Kevin P Davy
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, Virginia, USA
| | - Valisa E Hedrick
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, Virginia, USA
| | - D Travis Thomas
- Department of Athletic Training & Clinical Nutrition, University of Kentucky, Lexington, Kentucky, USA
| | - Brenda M Davy
- Department of Human Nutrition, Foods, and Exercise, Virginia Tech, Blacksburg, Virginia, USA
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Chryssanthopoulos C, Tsolakis C, Bottoms L, Toubekis A, Zacharogiannis E, Pafili Z, Maridaki M. Effect of a Carbohydrate-Electrolyte Solution on Fluid Balance and Performance at a Thermoneutral Environment in International-Level Fencers. J Strength Cond Res 2020; 34:152-161. [PMID: 30741860 DOI: 10.1519/jsc.0000000000003065] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Chryssanthopoulos, C, Tsolakis, C, Bottoms, L, Toubekis, A, Zacharogiannis, E, Pafili, Z, and Maridaki, M. Effect of a carbohydrate-electrolyte solution on fluid balance and performance at a thermoneutral environment in international-level fencers. J Strength Cond Res 34(1): 152-161, 2020-The purpose of the study was to examine a possible effect of a carbohydrate-electrolyte (CHO-E) solution on fluid balance and performance in fencing at a thermoneutral environment. Sixteen fencers performed two 120-minute training sessions separated by 7-14 days under similar environmental conditions (temperature: 20.3° C and humidity: 45-47%). Each session consisted of 60-minute conditioning exercises followed by 10 bouts of 3 minutes against the same opponent with 3-minute interval between each bout. Participants ingested at regular intervals either a 6% CHO-E solution or an artificially sweetened water (PL) in a counterbalanced order. No difference was observed between conditions in the heart rate responses, perceived exertion, changes in plasma volume, urine specific gravity, number of bouts won or lost, or points for and against. Considerable variability was observed in body mass changes that revealed significant differences at the time level (i.e., pre- vs. post-exercise) (F1,15 = 9.31, p = 0.008, η = 0.38), whereas no difference was found between conditions (i.e., CHO-E vs. PL) (F1,15 = 0.43, p = 0.52, η = 0.03) and conditions × time interaction (F1,15 = 3.57, p = 0.078, η = 0.19). Fluid loss was not significantly different between conditions (p = 0.08, d = 0.47). The blood glucose level was higher (p < 0.01) after exercise in CHO-E, whereas the blood lactate level was similar between conditions. In conclusion, the CHO-E solution was as effective as the artificially sweetened water in terms of fluid balance and fencing performance at a thermoneutral environment. Because of large individual variability, fencers should monitor their fluid intake and body fluid loss in training and competition.
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Affiliation(s)
- Costas Chryssanthopoulos
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, Athens, Greece.,Department of Experimental Physiology, Medical School, National and Kapodistrian University of Athens, Athens, Greece
| | - Charis Tsolakis
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Lindsay Bottoms
- Department of Psychology and Sports Science, School of Life and Medical Science, University of Hertfordshire, Hatfield, United Kingdom; and
| | - Argyris Toubekis
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Elias Zacharogiannis
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, Athens, Greece
| | - Zoi Pafili
- Department of Dietetics, Achillopoulion General Hospital, Volos, Greece
| | - Maria Maridaki
- School of Physical Education and Sports Science, National and Kapodistrian University of Athens, Athens, Greece
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Klimešová I, Krejčí J, Botek M, Neuls F, Sládečková B, Valenta M, Panská S. Hydration status and the differences between perceived beverage consumption and objective hydration status indicator in the Czech elite deaf athletes. ACTA GYMNICA 2019. [DOI: 10.5507/ag.2019.020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Jacob R, Couture S, Lamarche B, Provencher V, Morissette É, Valois P, Goulet C, Drapeau V. Determinants of coaches' intentions to provide different recommendations on sports nutrition to their athletes. J Int Soc Sports Nutr 2019; 16:57. [PMID: 31775807 PMCID: PMC6880347 DOI: 10.1186/s12970-019-0311-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2019] [Accepted: 09/10/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Coaches are considered as an important source of nutrition information by their athletes. However, their knowledge in this area is often insufficient for proper guidance and may lead to the dissemination of misinformation regarding sports nutrition. The aim of this study was to assess coaches' intentions as well as psychosocial determinants underlying their intentions to provide sports nutrition recommendations to their high school athletes. METHODS Coaches (n = 47) completed a Web-based questionnaire based on the theory of planned behaviour, to assess their intentions to provide three different sports nutrition recommendations and their determinants. Multiple regression analyses were used to identify the variables that were most strongly related to the intentions. RESULTS Forty-six, 44.7 and 91.9% of coaches had the intention to recommend a higher consumption of foods rich in carbohydrates, foods rich in proteins and an increase in hydration to their athletes, respectively. Subjective norm was the only significant determinant of coaches' intention to recommend a higher consumption of foods rich in carbohydrates (R2 = 53.7%, β = 0.73 ± 0.12, P < 0.0001). Subjective norm and perceived behavioural control were significantly associated with coaches' intentions to recommend a higher consumption of foods rich in proteins (R2 = 25.9%, β = 0.50 ± 0.16, P = 0.002 and R2 = 17.2%, β = 0.39 ± 0.17, P = 0.01, respectively) and an increase in hydration (R2 = 26.8%, β = 0.38 ± 0.13, P = 0.001 and R2 = 46.3%, β = 0.58 ± 0.11, P < 0.0001, respectively). CONCLUSIONS The results of this study suggest that subjective norm and perceived behavioural control represent important determinants of coaches' intentions to provide recommendations on sports nutrition. These findings should be considered in future interventions aimed at facilitating proper general sports nutrition recommendations provided by coaches to their athletes.
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Affiliation(s)
- Raphaëlle Jacob
- Institute of Nutrition and Functional Foods, Laval University, Quebec, G1V 0A6, Canada
- School of Nutrition, Laval University, Quebec, G1V 0A6, Canada
- Quebec Heart and Lung Institute Research Center, Quebec, G1V 4G5, Canada
- Centre de recherche interuniversitaire sur la formation et la profession enseignante (CRIFPE-Laval), Laval University, Quebec, G1V 0A6, Canada
| | - Steven Couture
- Institute of Nutrition and Functional Foods, Laval University, Quebec, G1V 0A6, Canada
- School of Nutrition, Laval University, Quebec, G1V 0A6, Canada
| | - Benoît Lamarche
- Institute of Nutrition and Functional Foods, Laval University, Quebec, G1V 0A6, Canada
- School of Nutrition, Laval University, Quebec, G1V 0A6, Canada
| | - Véronique Provencher
- Institute of Nutrition and Functional Foods, Laval University, Quebec, G1V 0A6, Canada
- School of Nutrition, Laval University, Quebec, G1V 0A6, Canada
| | - Éliane Morissette
- Institute of Nutrition and Functional Foods, Laval University, Quebec, G1V 0A6, Canada
- School of Nutrition, Laval University, Quebec, G1V 0A6, Canada
| | - Pierre Valois
- Department of Educational Fundamentals and Practices, Laval University, Quebec, G1V 0A6, Canada
| | - Claude Goulet
- Centre de recherche interuniversitaire sur la formation et la profession enseignante (CRIFPE-Laval), Laval University, Quebec, G1V 0A6, Canada
- Department of Physical Education, Laval University, Québec, G1V 0A6, Canada
| | - Vicky Drapeau
- Institute of Nutrition and Functional Foods, Laval University, Quebec, G1V 0A6, Canada.
- Quebec Heart and Lung Institute Research Center, Quebec, G1V 4G5, Canada.
- Centre de recherche interuniversitaire sur la formation et la profession enseignante (CRIFPE-Laval), Laval University, Quebec, G1V 0A6, Canada.
- Department of Physical Education, Laval University, Québec, G1V 0A6, Canada.
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Hydration Status and Fluid Needs of Division I Female Collegiate Athletes Exercising Indoors and Outdoors. Sports (Basel) 2019; 7:sports7070155. [PMID: 31247986 PMCID: PMC6681079 DOI: 10.3390/sports7070155] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2019] [Revised: 06/19/2019] [Accepted: 06/24/2019] [Indexed: 11/16/2022] Open
Abstract
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.
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Zubac D, Paravlic A, Reale R, Jelaska I, Morrison SA, Ivancev V. Fluid balance and hydration status in combat sport Olympic athletes: a systematic review with meta-analysis of controlled and uncontrolled studies. Eur J Nutr 2019; 58:497-514. [DOI: 10.1007/s00394-019-01937-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Accepted: 02/22/2019] [Indexed: 11/28/2022]
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Sekiguchi Y, Adams WM, Curtis RM, Benjamin CL, Casa DJ. Factors influencing hydration status during a National Collegiate Athletics Association division 1 soccer preseason. J Sci Med Sport 2018; 22:624-628. [PMID: 30587437 DOI: 10.1016/j.jsams.2018.12.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Revised: 09/29/2018] [Accepted: 12/08/2018] [Indexed: 11/18/2022]
Abstract
OBJECTIVES To investigate the roles that training load and environmental conditions have on fluid balance during a collegiate men's soccer preseason. DESIGN Observational study. METHODS Twenty-eight male collegiate soccer players (mean±SD; age, 20±1.7y; body mass (BM), 79.9±7.3kg; height, 180.9±6.8cm; body fat, 12.7±3.1%; VO2max, 50.7±4.3ml·kg-1·min-1) participated in this study. Prior to (PRE) and following (POST) each team session, BM, percent BM loss (%BML) and hydration status was measured. Participants donned a heart rate and GPS enabled monitor to measure training load. For all team activities, ambient temperature (TAMB) and relative humidity (RH) were obtained from the nearest local weather station. Participants consumed 500mL of water as part of the team-based hydration strategy before and after training session. Stepwise linear regression was used to identify the variables that predicted %BML. Significance was set a-priori p<0.05. RESULTS Total distance covered predicted %BML during all preseason activities (r2=0.253, p<0.001), with TAMB and RH further adding to the model (r2=0.302, p<0.001). %BML never exceeded 2% of BM during any one session and daily variation in BM was <1% from baseline measures. Urine specific gravity was greater than 1.020 on 12/15days and UCOL was above 4 on 13/15days, indicating a state of hypohydration. CONCLUSIONS Total distance covered was the best predictor for the extent of body water losses during a collegiate preseason. While the team-based hydration strategy during preseason was successful in minimizing fluid losses during activity, participants arrived hypohydrated 80% of the time, necessitating a greater focus on daily fluid needs.
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Affiliation(s)
- Yasuki Sekiguchi
- Korey Stringer Institute, Department of Kinesiology, University of Connecticut, USA.
| | - William M Adams
- Department of Kinesiology, University of North Carolina at Greensboro, USA
| | - Ryan M Curtis
- Korey Stringer Institute, Department of Kinesiology, University of Connecticut, USA
| | - Courteney L Benjamin
- Korey Stringer Institute, Department of Kinesiology, University of Connecticut, USA
| | - Douglas J Casa
- Korey Stringer Institute, Department of Kinesiology, University of Connecticut, USA
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Chia JS, Barrett LA, Chow JY, Burns SF. Effects of Caffeine Supplementation on Performance in Ball Games. Sports Med 2018; 47:2453-2471. [PMID: 28741186 DOI: 10.1007/s40279-017-0763-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Although a large body of evidence exists documenting the ergogenic properties of caffeine, most studies have focused on endurance performance. However, findings from endurance sports cannot be generalized to performance in ball games where, apart from having a high level of endurance, successful athletic performances require a combination of physiological, technical and cognitive capabilities. The purpose of this review was to critically evaluate studies that have examined the effect of a single dose of caffeine in isolation on one or more of the following performance measures: total distance, sprint performance, agility, vertical jump performance and accuracy in ball games. Searches of three major databases resulted in 19 studies (invasion games: 13; net-barrier games: 6) that evaluated the acute effects of caffeine on human participants, provided the caffeine dose administered, and included a ball games specific task or simulated match. Improvements in sprint performance were observed in 8 of 10 studies (80%), and vertical jump in 7 of 8 studies (88%). Equivocal results were reported for distance covered, agility and accuracy. Minor side effects were reported in 4 of 19 studies reviewed. Pre-exercise caffeine ingestion between 3.0 and 6.0 mg/kg of body mass appears to be a safe ergogenic aid for athletes in ball games. However, the efficacy of caffeine varies depending on various factors, including, but not limited to, the nature of the game, physical status and caffeine habituation. More research is warranted to clarify the effects of caffeine on performance measures unique to ball games, such as agility and accuracy. It is essential that athletes, coaches and practitioners evaluate the risk-benefit ratio of caffeine ingestion strategies on an individual case-by-case basis.
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Affiliation(s)
- Jingyi Shannon Chia
- Physical Education and Sports Science, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore, 637616, Singapore
- Institute for Sports Research, Nanyang Technological University, Singapore, Singapore
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Laura Ann Barrett
- School of Sport, Exercise and Health Sciences, Loughborough University, Loughborough, UK
| | - Jia Yi Chow
- Physical Education and Sports Science, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore, 637616, Singapore
| | - Stephen Francis Burns
- Physical Education and Sports Science, National Institute of Education, Nanyang Technological University, 1 Nanyang Walk, Singapore, 637616, Singapore.
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Ayotte D, Corcoran MP. Individualized hydration plans improve performance outcomes for collegiate athletes engaging in in-season training. J Int Soc Sports Nutr 2018; 15:27. [PMID: 29866199 PMCID: PMC5987390 DOI: 10.1186/s12970-018-0230-2] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 05/17/2018] [Indexed: 11/16/2022] Open
Abstract
Background Athletes commonly consume insufficient fluid and electrolytes just prior to, or during training and competition. Unlike non-athletes or athletes who do not engage in frequent rigorous and prolonged training sessions, “hard trainers” may require additional sodium and better benefit from a hydration plan tailored to their individual physiology. The purpose of this randomized cross-over study was to determine whether a hydration plan based off of an athlete’s sweat rate and sodium loss improves anaerobic and neurocognitive performance during a moderate to hard training session as well as heart rate recovery from this session. Methods Collegiate athletes who were injury free and could exercise at ≥ 75% of their maximum heart rate for a minimum of 45 min were recruited for this randomized, cross-over study. After completing a questionnaire assessing hydration habits, participants were randomized either to a prescription hydration plan (PHP), which considered sweat rate and sodium loss or instructed to follow their normal ad libitum hydration habits (NHP) during training. Attention and awareness, as well as lower body anaerobic power (standing long jump) were assessed immediately before and after a moderate to hard training session of ≥ 45 min. Heart rate recovery was also measured. After a washout period of 7 days, the PHP group repeated the training bout with their normal hydration routine, while the NHP group were provided with a PHP plan and were assessed as previously described. Results Fifteen athletes from three different sports, aged 20 ± 0.85 years, participated in this study. Most participants reported feeling somewhat or very dehydrated after a typical training session. Compared to their NHP, participants following a PHP jumped 4.53 ± 3.80 in. farther, tracked moving objects 0.36 ± 0.60 m/second faster, and exhibited a faster heart rate recovery following a moderate to hard training session of 45–120 min in duration. Conclusion A tailored hydration plan, based on an athlete’s fluid and sodium loss has the potential to improve anaerobic power, attention and awareness, and heart rate recovery time.
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Affiliation(s)
- David Ayotte
- Department of Health Sciences, Merrimack College, O'Reilly Hall, Room 414, 315 Turnpike Street, North Andover, MA, 01845, USA
| | - Michael P Corcoran
- Department of Health Sciences, Merrimack College, O'Reilly Hall, Room 414, 315 Turnpike Street, North Andover, MA, 01845, USA.
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Hew-Butler TD, Eskin C, Bickham J, Rusnak M, VanderMeulen M. Dehydration is how you define it: comparison of 318 blood and urine athlete spot checks. BMJ Open Sport Exerc Med 2018; 4:e000297. [PMID: 29464103 PMCID: PMC5812394 DOI: 10.1136/bmjsem-2017-000297] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/19/2017] [Indexed: 11/05/2022] Open
Abstract
Clinical medicine defines dehydration using blood markers that confirm hypertonicity (serum sodium concentration ([Na+])>145 mmol/L) and intracellular dehydration. Sports medicine equates dehydration with a concentrated urine as defined by any urine osmolality (UOsm) ≥700 mOsmol/kgH2O or urine specific gravity (USG) ≥1.020.
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Affiliation(s)
- Tamara D Hew-Butler
- Department of Human Movement Science, Exercise Science Program, Oakland University, Rochester, Michigan, USA
| | - Christopher Eskin
- Department of Human Movement Science, Exercise Science Program, Oakland University, Rochester, Michigan, USA
| | - Jordan Bickham
- Department of Human Movement Science, Exercise Science Program, Oakland University, Rochester, Michigan, USA
| | - Mario Rusnak
- Department of Human Movement Science, Exercise Science Program, Oakland University, Rochester, Michigan, USA
| | - Melissa VanderMeulen
- Department of Human Movement Science, Exercise Science Program, Oakland University, Rochester, Michigan, USA
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Progressive Dehydration in Junior Laser Class Sailors During World Championship. Int J Sport Nutr Exerc Metab 2018; 28:75-81. [PMID: 29035599 DOI: 10.1123/ijsnem.2017-0142] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The purpose of this article is to assess the hydration status of elite young sailing athletes during World Championship competition. Twelve young, elite, male, Laser Class sailors (age: 15.8 ± 1.1 y, height: 1.74 ± 0.1 m, weight: 65.1 ± 1.5 kg, body fat: 12.5 ± 3.1%, training experience: 7.0 ± 1.2 y) participated in this descriptive study. After three-day baseline bodyweight measurements, hydration status was assessed via pre- and post-race body weights, urine-specific gravity, and thirst ratings via a visual analog scale during four consecutive days of racing. Measurements and data collection took place at the same time each racing day, with mean environmental temperature, humidity, and wind speed at 23.0 ± 0.8°C, 64-70%, and 9 ± 1 knots, respectively. Average racing time was 130 ± 9 min. Body weight was significantly decreased following each race-day as compared to prerace values (Day 1: -1.1 ± 0.2, Day 2: -2.5 ± 0.1, Day 3: -2.8 ± 0.1, and Day 4: -3.0 ± 0.1% of body weight; p < 0.05). The participants exhibited dehydration of -2.9 ± 0.2 and -5.8 ± 0.2% of body weight before and after the fourth racing day as compared to the three-day baseline body weight. Urine-specific gravity (pre-post → Day 1: 1.014-1.017; Day 2: 1.019-1.024; Day 3: 1.021-1.026; Day 4: 1.022-1.027) and thirst (pre-post → Day 1: 2.0-5.2; Day 2: 3.2-5.5; Day 3: 3.7-5.7; Day 4: 3.8-6.8) were also progressively and significantly elevated throughout the four days of competition. The data revealed progressive dehydration throughout four consecutive days of racing as indicated by decreased body weight, elevated urine concentration, and high thirst.
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Nuccio RP, Barnes KA, Carter JM, Baker LB. Fluid Balance in Team Sport Athletes and the Effect of Hypohydration on Cognitive, Technical, and Physical Performance. Sports Med 2017; 47:1951-1982. [PMID: 28508338 PMCID: PMC5603646 DOI: 10.1007/s40279-017-0738-7] [Citation(s) in RCA: 95] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Sweat losses in team sports can be significant due to repeated bursts of high-intensity activity, as well as the large body size of athletes, equipment and uniform requirements, and environmental heat stress often present during training and competition. In this paper we aimed to: (1) describe sweat losses and fluid balance changes reported in team sport athletes, (2) review the literature assessing the impact of hypohydration on cognitive, technical, and physical performance in sports-specific studies, (3) briefly review the potential mechanisms by which hypohydration may impact team sport performance, and (4) discuss considerations for future directions. Significant hypohydration (mean body mass loss (BML) >2%) has been reported most consistently in soccer. Although American Football, rugby, basketball, tennis, and ice hockey have reported high sweating rates, fluid balance disturbances have generally been mild (mean BML <2%), suggesting that drinking opportunities were sufficient for most athletes to offset significant fluid losses. The effect of hydration status on team sport performance has been studied mostly in soccer, basketball, cricket, and baseball, with mixed results. Hypohydration typically impaired performance at higher levels of BML (3-4%) and when the method of dehydration involved heat stress. Increased subjective ratings of fatigue and perceived exertion consistently accompanied hypohydration and could explain, in part, the performance impairments reported in some studies. More research is needed to develop valid, reliable, and sensitive sport-specific protocols and should be used in future studies to determine the effects of hypohydration and modifying factors (e.g., age, sex, athlete caliber) on team sport performance.
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Affiliation(s)
- Ryan P Nuccio
- Gatorade Sports Science Institute, 617 W. Main St., Barrington, IL, 60010, USA.
| | - Kelly A Barnes
- Gatorade Sports Science Institute, 617 W. Main St., Barrington, IL, 60010, USA
| | - James M Carter
- Gatorade Sports Science Institute, 617 W. Main St., Barrington, IL, 60010, USA
| | - Lindsay B Baker
- Gatorade Sports Science Institute, 617 W. Main St., Barrington, IL, 60010, USA
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McDermott BP, Anderson SA, Armstrong LE, Casa DJ, Cheuvront SN, Cooper L, Kenney WL, O'Connor FG, Roberts WO. National Athletic Trainers' Association Position Statement: Fluid Replacement for the Physically Active. J Athl Train 2017; 52:877-895. [PMID: 28985128 PMCID: PMC5634236 DOI: 10.4085/1062-6050-52.9.02] [Citation(s) in RCA: 202] [Impact Index Per Article: 28.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
OBJECTIVE To present evidence-based recommendations that promote optimized fluid-maintenance practices for physically active individuals. BACKGROUND Both a lack of adequate fluid replacement (hypohydration) and excessive intake (hyperhydration) can compromise athletic performance and increase health risks. Athletes need access to water to prevent hypohydration during physical activity but must be aware of the risks of overdrinking and hyponatremia. Drinking behavior can be modified by education, accessibility, experience, and palatability. This statement updates practical recommendations regarding fluid-replacement strategies for physically active individuals. RECOMMENDATIONS Educate physically active people regarding the benefits of fluid replacement to promote performance and safety and the potential risks of both hypohydration and hyperhydration on health and physical performance. Quantify sweat rates for physically active individuals during exercise in various environments. Work with individuals to develop fluid-replacement practices that promote sufficient but not excessive hydration before, during, and after physical activity.
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Zubac D, Antelj T, Olujic D, Ivancev V, Morrison SA. Fluid balance and hydration assessment during the weight-stable preparation phase in elite youth boxers. J Sports Sci 2016; 35:719-726. [DOI: 10.1080/02640414.2016.1184302] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Effects of mild hypohydration on cooling during cold-water immersion following exertional hyperthermia. Eur J Appl Physiol 2016; 116:687-95. [DOI: 10.1007/s00421-016-3329-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 01/05/2016] [Indexed: 10/22/2022]
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