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To promote safe supplement use, athletes are advised to choose third-party tested (TPT) supplements to minimise doping risk. This study evaluated changes in knowledge on supplements in US high school athletes from a 2-week online supplement education programme. One group of sophomores (ED, n = 48) completed a Canvas course on safe supplement use, based on the Theory of Planned Behaviour, while the other group of freshmen (NOED, n = 38) did not. Participants completed questionnaires pre- and post-intervention to assess practical knowledge of finding and ordering TPT supplements, familiarity with World Anti-Doping Agency (WADA) banned substances and decision-making in supplement purchasing. Chi-Square and McNemar tests were applied with significance set at p ≤ 0.05. Pre-intervention no differences were found between groups (ages 14-17 years, 39.5% female) for any knowledge questions (p = 0.18). Post-intervention, ED participants were more likely to know where to find (58.3% vs. 39.5%, p = 0.041), and order (62.5% vs. 28.9%, p = 0.001) TPT supplements, and more athletes in ED (72.9%) than NOED (40.0%) reported deciding to purchase supplements themselves (p = 0.015). Parents were less influential in ED (75.0% vs. 92.1%, p = 0.019). Importantly, positive changes over time were larger for ED versus NOED in knowing where to find (28% vs. 13%, p = 0.04) and order (28% vs. 7%, p < 0.001) TPT supplements and WADA familiarity (19% vs. 5%, p = 0.01). Within-group changes showed ED improved on all practical knowledge questions (p = <0.001-0.008), whereas NOED only increased in knowing where to find TPT supplements (p = 0.003). These findings suggest an online educational programme may enhance practical knowledge of safe supplement use among high school athletes., (© 2024 British Nutrition Foundation.)

This article provides a recap of the 10 Questions/10 Experts session at the 2024 American College of Sports Medicine Annual Meeting. Each of the speakers considered the validity of common "myths," while providing evidence-based opinions to support, or, bust, myths addressing the following questions: (1) Would 100 g/hr of carbohydrate be advisable for the Olympic Cycling Road race? (2) Is there an advantage in the marathon of ingesting bicarbonate as a hydrogel product? (3) Can genotyping be used to individualize caffeine supplementation in football? (4) Should low fluid consumers drink more to improve 1,500-m track performance? (5) Do urinary markers of dehydration predict poor basketball performance? (6) Do placebo effects influence 10-km track performance? (7) Should combat athletes make weight using glucagon-like peptide-1 receptor agonists? (8) Would crushed ice ingestion help tennis umpires make better decisions in the heat? (9) Are collagen supplements useful to reduce tendon and ligament injuries in volleyball? and (10) Should female athletes plan their training and diet according to their menstrual cycle? This article describes the content of each of the presentations including the most important outcomes and conclusions drawn by the presenters.

Context: The training stress of heat acclimatization optimizing exercise performance in a hot environment can be demanding., Objectives: This study evaluated the efficiency of different single heating protocols to elevate core temperature., Design: Not randomized controlled trial., Setting: Passive heating (PAS), 30-min active heating using a high-intensity bike protocol (HIBP) in a hot environment with 30-min passive heating (EH-PAS), 60-min HIBP in a hot environment (EH), or 60-min HIBP at room temperature (EM)., Participants: Ten male participants (25±3 years) performed four different 60-min heating strategies at least one week apart., Main Outcome Measures: Body core temperature and heart rate., Results: The highest peak gastrointestinal temperature occurred in EH-PAS (39.1±0.4°C), followed by EH (38.9±0.3°C), EM (38.4±0.3°C), and PAS (38.1±0.5°C). The average HR, measured as a control for intensity, was not different between exercise strategies (EH-PAS: 142±12.3, EH: 146±9.7, and EM: 142±13.3, p>0.05), while different from PAS: 98±15.2 bpm, p<0.05., Conclusions: Adding passive heating to a shorter exercise protocol can be just as effective in keeping core temperature elevated as exercise in the heat alone during a 60-minute session. Therefore, a single-bout combination of exercise and passive heating may result in a similar body temperature induction compared to exercise heat stress alone.

Background: Athletes often report gastrointestinal (GI) complaints. Standardized validated tests validated in athletes are lacking., Objective: The objective of the current study was to investigate the test-retest reliability of the gastrointestinal symptoms rating scale (GSRS), a disease-specific instrument of 15 items to quantify the severity of various GI symptoms., Methods: For this purpose, a 3-week repeated measurements design was used. The mean difference (Wilcoxon signed rank test), associations (Spearman correlations), and systematic difference using Bland-Altman calculations for repeated measurements, as well as its internal consistency (Cronbach's alpha) on testing day 1 and day 2 were analyzed, with significance set at p ≤ 0.05. A total of n = 70 well-trained athletes (26.1 ± 5.4 years, of which 40% were female) were included., Results: A high Cronbach's α for GSRS was found on testing day 1 (0.825), and day 2 (0.823), suggesting a good and comparable internal consistency of the questionnaire. When assessing the multilevel temporal stability for total GSRS scores (28.0, IQR 22.0-36.3 vs 26.5, IQR 18.0-35.0), there was a small but significant difference (Z =  - 2.489, and p = 0.013), but a fair correlation between day scores (r = 0.68, p < 0.001), and a Bland-Altman reporting difference between questionnaires within 10% of the total GSRS score, without significant reporting bias (p = 0.38). In most cases, except for hunger, burping, and loose stools, the individual GSRS items were reported in line with total scores and similar for sex., Conclusion: In conclusion, the GSRS is reliable when used with athletes, with good internal consistency for most symptoms independently of sex, except for hunger, burping, and loose stools., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Use of food supplements (FS) by athletes is well characterised but there is little information on 'herbal' or 'botanical' FS beyond 'natural'. This study determined, by questionnaire, whether athletes' main self-reported reason for using FS was reflective of what was written on product labels or, when these claims were unavailable, was in accordance with the scientific literature. In 217 elite (n = 55) and amateur (n = 162) athletes living on the island of Ireland, 71% (n = 153) consumed any kind of FS, with 16% (n = 34) of the entire cohort deemed botanical consumers. 'Protein' (21%, n = 46), 'vitamin D' (17%, n = 37) and 'vitamin C' (15% n = 32) were most consumed with the top reasons for use being 'to support health', 'to prevent illness/for immunity purposes' and 'recovery'. There was generally good agreement between approved nutrition and health claims for such products and athletes' main reported reasons for use. Only the amateur athletes in our pool described using botanical supplements, with reasons for use stated as 'sleep improvement' (21%), 'recovery' (14%), 'supporting health' (12%) and 'energy' (12%), resulting in poor agreement with either approved claims or scientific evidence. Only half of amateur athletes knew if their botanical FS were third-party tested. Athletes and practitioners require guidance to avoid consuming supplements for which there is little scientific evidence, and which may risk being contaminated/fraudulent., (© 2024 The Author(s). Nutrition Bulletin published by John Wiley & Sons Ltd on behalf of British Nutrition Foundation.)

Background: Energy expenditure may be difficult to assess when hiking difficult trails. Case presentation: We measured physical activity exercise energy expenditure (PAEE) directly from oxygen uptake using a mobile device (cardiopulmonary exercise testing, CPET), and by using a formula based on heart rate (HR), or metabolic equivalent values from the Compendium of Physical Activity, and other physiological outcomes. Outcomes and implications: Total PAEE (1342 kcal) using CPET showed a two-fold difference between ascending and descending (887 vs. 455 kcal) during a 124-min hike. For HR, PAEE was 1893kcal (+551 kcal overreporting), while compendium-based scenarios ranged from 1179 to 1446 kcal, which was in closer range (-163 to +104 kcal/min) compared to the CPET data. Fluid consumption was 1300 mL/hour, with 1.1% bodyweight loss, peak skin temperature of 35.2°C and core body temperature of 39.2°C. Recommendations: Tables reasonably predict energy expenditure while not precisely reflecting the actual situation., Competing Interests: Declaration of conflicting interestsThe authors report there are no competing interests for this project, but FW received grants from external partners that were not related to this project. FW received grants from: Arizona Parks & Trails, Pac-12 Health and Wellbeing Initiative, the Collegiate and Professional Sports Dietetic Organization, Friesland Campina N.V., Standard Process Inc., Kraft Heinz Company, FEMA, and the Arizona Board of Regents.

Context: Nutritional supplement use in athletes is common, accompanied by potential doping risk., Objective: Determine athletes' nutritional supplement and third-party tested (TPT) supplement use, supplement knowledge as well as factors influencing their behavior., Design: Cross-Sectional Study., Setting: NCAA DI athletic departments., Participants: Student-athletes (n=410, 53% female, age 21.4±1.6 years)., Main Outcome Measures: Survey questions addressed topics including nutritional supplement knowledge and use, TPT supplement knowledge, use and logo recognition and data were 11 stratified for sex differences., Results: Athletes (91%) report the use of supplements, but the total number of supplements used (median and interquartile range, IQR) is lower in females (7, 4-11), than males (9, 4-12), with U=17960, p=0.01. A total of 48% (n=191, out of 402 responses) reported purchasing supplements outside of their athletic department, with significantly fewer females (40%, n=84) than males (56%, n=107) reporting this behavior (χ2=11.20, p<0.001). No association between TPT logo recognition and TPT use was seen (χ2=0.238, p=0.63). Of all athletes using supplements, 38% (n=140) reported "consistent TPT use", while females (36%, n=70) reported this less often than males (41%, n=70, χ2=0.952, p<0.32). No sex differences were seen for receiving nutritional counseling (89%, p=0.37), or the low nutritional supplement knowledge (<50%, p=0.38), however, males had 2.5 times greater odds at recognizing a TPT organization logo than females (OR=2.45, with 95% CI=1.58-3.79)., Conclusions: Most athletes use nutritional supplements. Females report slightly fewer supplements than males, while also less frequently purchasing them outside their athletic department, potentially explaining the lower TPT logo recognition in female athletes.

The current state of the literature lacks a clear characterization of gastrointestinal (GI) symptoms, gut microbiota composition, and general physical and mental wellbeing in well-trained athletes. Therefore, this study aimed to characterize differences in self-reported symptoms, gut microbiota composition, and wellbeing (i.e., sleep quality, mood, and physical (PHQ) and mental wellbeing) between athletes with and without GI symptoms. In addition, we assessed the potential impact of a 3-week multi-ingredient fermented whey supplement in the GI complaints group, without a control group, on the gut microbiota and self-reported GI symptoms and wellbeing. A total of 50 athletes (24.7 ± 4.5 years) with GI issues (GI group at baseline, GI-B) and 21 athletes (25.4 ± 5.3 years) without GI issues (non-GI group, NGI) were included. At baseline, there was a significant difference in the total gastrointestinal symptom rating scale (GSRS) score (24.1 ± 8.48 vs. 30.3 ± 8.82, p = 0.008) and a trend difference in PHQ (33.9 ± 10.7 vs. 30.3 ± 8.82, p = 0.081), but no differences ( p > 0.05) were seen for other outcomes, including gut microbiota metrics, between groups. After 3-week supplementation, the GI group (GI-S) showed increased Bifidobacterium relative abundance ( p < 0.05), reported a lower number of severe GI complaints (from 72% to 54%, p < 0.001), and PHQ declined ( p = 0.010). In conclusion, well-trained athletes with GI complaints reported more severe GI symptoms than an athletic reference group, without showing clear differences in wellbeing or microbiota composition. Future controlled research should further investigate the impact of such multi-ingredient supplements on GI complaints and the associated changes in gut health-related markers.

Introduction: The aim of this cross-sectional study was to develop an algorithm to predict athletes use of third-party tested (TPT) supplements. Therefore, a nutritional supplement questionnaire was used with a section about self-reported TPT supplement use., Methods: Outcomes were randomly assigned to a training dataset to identify predictors using logistic regression models, or a cross-validation dataset. Training data were used to develop an algorithm with a score from 0 to 100 predicting use or non-use of TPT nutritional supplements., Results: A total of n = 410 NCAA Division I student-athletes (age: 21.4 ± 1.6 years, 53% female, from >20 sports) were included. Then n = 320 were randomly selected, of which 34% ( n = 109) of users consistently reported that all supplements they used were TPT. Analyses resulted in a 10-item algorithm associated with use or non-use of TPT. Risk quadrants provided the best fit for classifying low vs. high risk toward inconsistent TPT-use resulting in a cut-off ≥60% (χ 2 (4) = 61.26, P < 0.001), with reasonable AUC 0.78. There was a significant association for TPT use (yes/no) and risk behavior (low vs. high) defined from the algorithm (χ 2 (1)=58.6, P < 0.001). The algorithm had a high sensitivity, classifying 89% of non-TPT users correctly, while having a low specificity, classifying 49% of TPT-users correctly. This was confirmed by cross-validation ( n = 34), reporting a high sensitivity (83%), despite a lower AUC (0.61)., Discussion: The algorithm classifies high-risk inconsistent TPT-users with reasonable accuracy, but lacks the specificity to classify consistent users at low risk. This approach should be useful in identifying athletes that would benefit from additional counseling., Competing Interests: FW and CG received grants from external partners during the last 5 years that were not related to this project. FW received grants from: Arizona Parks & Trails, Pac-12 Health and Wellbeing Initiative, the Collegiate and Professional Sports Dietetic Organization, Friesland Campina N.V., Standard Process Inc., Kraft Heinz Company, FEMA, Unilever Corporation, and the Arizona Board of Regents. CG received grants from the National Institutes of Health and Beyond Meat. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Wardenaar, Schott, Seltzer and Gardner.)

The World Cup is traditionally held oppressive thermal conditions. Therefore, teams should follow heat strain mitigation strategies, including optimal fluid ingestion. The objective of this analysis was to assess and visually communicate match-based World Cup player hydration opportunities and behaviors. Broadcast recordings of the 2018 World Cup (June-July) were analyzed. Descriptive data were reported for match duration, the number, type, and duration of breaks, and player-initiated hydration moments, as well as environmental conditions categorized as 'no thermal stress' and 'thermal heat stress.' The median number and interquartile range of total match breaks were 7 [5-8] during official breaks, with a duration of 42 [23-72] seconds. There were 2 [1-3] player-initiated hydration moments per game, with a duration of 77 [55-100] seconds. On top of the 29% (#126) of breaks in which drinking occurred, an additional 26% (#33) of self-initiated drinking was registered with a duration of 7 [4-28] seconds without an official break. There was no significant difference (P = 0.22) in self-initiated hydration between thermal conditions. Relative percentages showed suboptimal use of substitution (14%) and VAR (38%) breaks vs. injury breaks (75%). In conclusion, football players did not sufficiently use available breaks to hydrate.

Purpose: Relationships between body weight, urine color (Uc), and thirst level (WUT) have been proposed as a simple and inexpensive self-assessment method to predict dehydration. This study aimed to determine if this method also allowed us to accurately identify a low vs. high urine concentration in (tactical) athletes., Methods: A total of n = 19 Army Reserve Officer Training Corps cadets and club sports athletes (22.7 ± 3.8 years old, of which 13 male) were included in the analysis, providing morning body weight, thirst sensation, and Uc for five consecutive days. Each item received a score 0 or 1, resulting in a WUT score ranging from 0 (likely hydrated) to 3 (very likely dehydrated). WUT model and individual item outcomes were then compared with a ≥ 1.020 urine specific gravity (USG) cut-off indicating a high urine concentration, using descriptive comparisons, generalized linear mixed models, and logistic regression (to calculate the area under the curve (AUC))., Results: WUT score was not significantly predictive of urine concentration, z = 1.59, p = 0.11. The AUC ranged from 0.54 to 0.77 for test days, suggesting a fair AUC on most days. Only Uc was significantly related to urine concentration, z = 2.49, p = 0.01. The accuracy of the WUT model for correctly classifying urine samples with a high concentration was 68% vs. 51% of samples with a low concentration, resulting in an average accuracy of 61%., Conclusion: This study shows that WUT scores were not predictive of urine concentration, and the method did not substantially outperform the accuracy of Uc scoring alone., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany.)

The use of nutritional supplements can lead to doping risk and no data exist on high school athletes' use of certified third-party tested supplements. A cross-sectional cohort design was developed using an anonymous survey. Descriptive data for supplement use, use of third-party tested supplements, and knowledge in high school athletes were reported. A total of 225 high school athletes, ranging from 14-19 years of age, from a private high school in the western US, were included in the analysis of the results. A total of 94% (n=211) of athletes reported nutritional supplement use within the past year with an average of six (interquartile range: 3-9) individual supplements, ranging from 0-20 supplements per person. Most frequently reported were sports drinks (72%), vitamins (65%), sports bars (60%), protein powder (58%), caffeine (37%, as part of normal beverages, or 13% as a supplement), followed by creatine (23%). A total of 24% claimed to know for sure that all their supplements were third-party tested. In addition, the recognition of third-party testing organization icons was low (46% in supplement users vs. 14% in nonusers). Athletes also scored low in reporting how to find (22%) and how to order (25%) third-party tested supplements. In conclusion, almost all athletes in this study reported the use of multiple nutritional supplements annually. Only one-fourth of the athletes reported consistently using third-party tested supplements. Knowledge of where and how tested supplements could be purchased was limited in this high school athlete population.

Many high school athletes report using nutritional supplements. Due to a lack of education at the high school level, the use of safe for sports third-party tested nutritional supplements may be limited. To determine the impact of a short online nutritional supplement education program on safe dietary supplement behavior a cross-sectional repeated measures design was used. Therefore, a convenience sample of 106 high school athletes (14-19 years old) was recruited to measure pre-post education difference for nutritional supplement use and third-party tested (TPT) supplements. Additionally, it was analyzed if nutritional supplement related Theory of Planned Behavior (TPB) constructs were associated with athlete choices. The most popular supplements included protein powder (65%), caffeine from beverages (45%), and different types of vitamins (ranging from 38-44%). Consistent use of (safe) third-party tested individual supplements was low, ranging from 35-77% for the most frequently reported supplements. The combined TPB determinants explained 26% of the variance of the intention to use safe supplements (F 3, 102 = 13.03, p  < 0.001, Adj R 2 = 0.26). The self-reported intention to use third-party tested supplements increased significantly (+7%-36% per individual supplement) after following the education program ( Z  = -3.288, p  = 0.001) resulting in an intentional use of 54-94% TPT supplements. In conclusion, education resulted in more high school athletes reporting future third-party tested supplements use, and TPB construct scores did not change over time but could explain a substantial part of the variance of safe supplement use intentions.

ObjectiveTo examine funding and college-provided nutritional resources and to assess whether these are associated with diet quality and subsequent dietitian referral among female collegiate athletes of different sports levels. Participants: Female athletes (N = 120) from NCAA, NJCAA, and Club sports. Methods: Differences in questionnaire-based demographics, diet quality, and dietitian referrals were analyzed using Kruskal-Wallis and Chi-Square tests, with p  < 0.05. Factors associated with diet quality and dietitian referral were examined using regression. Results: NCAA reported more funding than Club and NJCAA ( p  < 0.05). NJCAA expressed insufficient funds for purchasing food and reported fewer college-provided nutritional resources ( p  < 0.05) while showing lower diet quality scores and higher subsequent dietitian referrals than NCAA and Club. No significant associations for dietary quality and dietitian referrals were found. Conclusions: Athletes across all sports levels reported insufficient funds for purchasing food and low diet quality, with NJCAA, showing the least funding and fewest nutritional resources.

Gastrointestinal (GI) symptoms may limit performance, but their prevalence and impact among team sports athletes is not well-documented. The objective of this study was to examine the prevalence of GI symptoms in a small sample of collegiate DI American football athletes, using a survey including the Gastrointestinal Symptoms Ratings Scale (GSRS). Forty-six athletes responded to the survey and reported scores for the 15-question GSRS with additional questions about dietary habits and supplement use. A total of 44 athletes were included in the study (45% of the current roster, age: 20.7 ± 1.7 years, 50% Afro-American or black, 39% skill position, 18% NSAIDs use, and 41% reporting protein supplement use); approximately half of the athletes (52%) reported experiencing GI complaints during exercise. Two-thirds of the athletes (61%) reported at least one or more GI symptoms in general, and 50% reported at least four moderate complaints. Seven athletes (16%) reported ≥2 severe GI symptoms with 5-13 moderate complaints. The most reported symptom was stomach pain (39%, n = 17), followed by hunger pain (36%, n = 16). Athletes reporting the use of protein supplements reported a higher GSRS score (22.0 and interquartile range (IQR) 17.0-31.8) vs. athletes not reporting protein use (15.0 and IQR 15.0-19.3), p = 0.001. Most athletes surveyed reported experiencing GI symptoms. A small group of these athletes reported multiple, varied, and severe symptoms that were associated with self-reported protein supplement use. In conclusion, the number of complaints varied among athletes, confirming the value of integrating the GSRS for screening purposes, and the expected need for individual dietary treatment approaches.

Athletes should carefully consider the use of botanical food supplements (BFSs) given the current lack of substantiation for botanical nutrition and health claims under EU and UK food laws. In addition, athletes may be at an increased risk of doping violations and other adverse outcomes potentially associated with BFS use; however, little is known about athletes' intake, knowledge, or perceptions in relation to BFS use. An online cross-sectional survey of n = 217 elite and amateur athletes living on the island of Ireland was conducted using Qualtrics XM to assess intake, knowledge, attitudes, and perceptions. General food supplements (FSs) were reported by approximately 60% of the study cohort, and 16% of the supplements reported were categorized as BFS. The most frequently consumed BFSs were turmeric/curcumin (14%), Ashwagandha (10%), and Beetroot extract (8%). A higher proportion of amateur athletes would source information about BFSs from less credible sources, such as fellow athletes, or from internet sources or their coach, compared to elite athletes. Those who sourced information about botanicals from fellow athletes ( p = 0.03) or the internet ( p = 0.02) reported a lower perceived level of risks associated with BFS use. This study therefore suggests that amateur athletes may be more likely to source information from less credible sources compared to elite athletes who may have more access to nutrition professionals and their knowledge/advice. This may have potential adverse implications for amateur athletes, e.g., Gaelic games players, who are included within the doping testing pool but who may not have access to evidence-based nutrition advice.

Background: Education may improve hiker safety on trails. Aim: To investigate the impact of an educational video on hiker fluid selection and fluid consumption in a hot environment. Methods: Quasi-experimental field study at hiking trails in which the intervention group (INT) viewed a three-minute hydration education video, whereas the control group (CON) did not. Before the hike, all hikers were asked if they wanted to select extra fluid, which was provided by the research team. Results: A total of n  = 97 hikers participated in the study, with n  = 56 in INT (32 male) and n  = 41 in CON (25 male). Despite absolute differences in environmental conditions, the differences fell within the same WBGT category. The total amount of fluid brought to the trails by participants was different between INT: 904 (503-1758) mL and CON: 1509 (880-2176) mL ( P  = 0.006), but participants in the INT group selected extra fluid (41%; n  = 23) significantly more often when compared with participants in the CON group (7%; n  = 3; P  < 0.001). As a result, there was no difference in the amount of fluid brought on the trail between INT: 1047 (611-1936) mL and CON: 1509 (932-2176) mL ( P  = 0.069), nor for fluid consumption between INT: 433 (289-615) mL/h and CON: 489 (374-719) mL/h ( P  = 0.18). Conclusions and Implications: A 3-min educational video may encourage hikers to select additional fluid before the start of their hike but does not appear to increase fluid intake.

Background: No study has evaluated the effect of macronutrient feedings on golf performance. Aim: Determine the effect of feedings during simulated golf game using a randomized cross-over study design. Methods: Male participants (n = 6, USGA handicap index 8.5 ± 6.72) played three standardized nine-hole rounds, consuming 30 g of carbohydrate, 15 g + 15 g protein and carbohydrate, or a zero-calorie control. Measurements of driving, chipping, and putting distance and accuracy were taken, as well as perceived levels of fatigue and alertness. Results: No relevant differences ( P  > 0.05) were seen in golf performance or alertness, but self-reported fatigue differed between conditions ( P   =  0.02), with scores of 2.5 (0.8 to 3.6) for the combination of carbohydrate and protein, 3.0 (1.5 to 4.3) for carbohydrate, and 4.0 (2.9 to 6.5) for the control, with higher levels indicating more fatigue. Conclusion: Macronutrient feedings led to a significantly lower level of self-reported fatigue without affecting golf performance and alertness compared to a control.

Background: Females are prone to urinary tract infections (UTIs) due to estrogen fluctuations affecting vaginal flora. While menstruating, increased fluid consumption to support urination frequency and void volume may be important, as the urethra and urinary tract are more predisposed to bacteria, particularly UTI pathogens. Aim: This study aimed to investigate the impact of hydration on urinary tract health during menstruation among underhydrated premenopausal women. Methods: Thirteen females participated in a 60-day 2 × 2 randomized crossover trial to evaluate the effectiveness of consuming ≥2.2 L of total beverage fluid intake, with 1.9 L being water, (intervention, INT) and maintaining habitual fluid intake (control, CON) on two subsequent menses. Participants completed fluid and urination diaries at days 2 and 5 after the onset of bleeding (day 1) to determine the fluid amount consumed and urination frequency. Urine concentration was assessed in afternoon (days 2 and 5) and uropathogenic bacterial activity in first-morning (days 3 and 6) urinations. General linear models assessed differences in bacterial and hydration outcomes. Results: The intervention led to a 62% mean total fluid increase, INT 3.0 ± 1.1 L and CON 1.9 ± 0.9 L, p  < 0.001, η 2  = 0.459. Urination frequency was greater and urine concentration less in the INT to CON, all p s  < 0.05, η 2 range = 0.023-0.019. Only four cultures detected uropathogenic bacteria, with no patterns between conditions or days, making it difficult to determine the intervention's effectiveness. Conclusion: Fluid intake increased, and hydration status improved. No differences in uropathogenic bacterial activity were seen between the hydration and control conditions.

Background: A wide range of sports health professionals provide nutritional supplement advice. We aimed to better understand the expertise, knowledge, and attitudes of sports health professionals toward nutritional supplements and third-party supplement testing., Methods: A web-based questionnaire was used to ask questions about nutritional supplement knowledge and attitudes toward the Dutch third-party supplement testing system (NZVT), about supplement efficacy, and if professionals advise these supplements, as well as which profession can be deemed the expert on nutritional supplements., Results: A total of n = 320 sports health professionals delivered input, of which 45% worked with Olympic athletes and 18% were sports dietitians. Sports dietitians were ranked as the most knowledgeable professionals about sports nutrition (80%) and nutritional supplements (74%), and a literature-based comparison showed the most favorable knowledge, attitudes, and ergogenic classifications of supplement scores for sports dietitians compared with other sports health professions. Sports health professionals working with Olympic athletes scored similar but slightly lower trends on self-reported knowledge, attitude and third-party supplement testing than sports dietitians but substantially better than professionals not working with Olympic athletes., Conclusion: Sports dietitians are seen as the absolute expert on supplements by other sports health professionals, with professionals working with Olympic athletes reporting similar trends, and other sports health professionals do have lower self-reported knowledge and preferred attitudes toward effective and safe use of dietary supplements.

The purpose of this study was to evaluate nutrition knowledge and diet quality in collegiate athletes to determine if referral to a sports registered dietitian (RD) is warranted. This cross-sectional study analyzed four sections of the Nutrition for Sport Knowledge Questionnaire and the Rapid Eating Assessment for Patients Questionnaire, both validated in athletic populations. The relationship between nutrition knowledge and diet quality was evaluated. Significance was set at P  ≤ 0.05. One hundred and twenty athletes reported a median nutrition score of 52 (45-61), and a dietary quality score of 53 (46-58), with a weak, positive association between both ( r  = 0.28 (95% CI: 0.11-0.44), P  < 0.01). Fifty-four percent were categorized as needing a referral to a sports RD. Diet quality scores differed between dietitian referral group with 49 (43-54) versus 58 (52-62) for the nonreferral group, respectively ( P  < 0.01, V = 0.71), with no difference in nutrition knowledge observed, P  = 0.73. Overall, nutrition knowledge and diet quality in our sample of collegiate athletes was poor. College athletic departments with limited access to sports RD should use these questionnaires to evaluate knowledge and the need of dietitian referral separately.

We aimed to assess the association between gastrointestinal (GI) injury, complaints, and food intake in 60-km ultramarathon runners. Thirty-three ultramarathon runners provided pre- and post-race blood samples for assessment of GI injury by intestinal fatty-acid binding protein (I-FABP), and inflammatory response by interleukin (IL)-6, IL-8, tumour necrosis factor alpha (TNF-α), and C-reactive protein (CRP). GI complaints and nutritional intake were reported by a post-race questionnaire. GI complaints were reported by 73% of the runners, of which 20% reported 1 or 2 severe complaints. IL-6, IL8, TNF-α, and CRP increased significantly from pre- to post-race ( P < 0.001 for all biomarkers), while I-FABP did not (1375 [IQR: 1264-2073] to 1726 [IQR: 985-3287] pg/mL; P = 0.330). The 'GI complaints score', as the integral of the number and severity of GI complaints, did not correlate with ΔI-FABP (rs: -0.050, P = 0.790) or energy intake (rs: 0.211, P = 0.260). However, there was a significant negative correlation between energy intake and ΔI-FABP (rs: -0.388, P = 0.031). In conclusion, GI complaints were neither associated with food intake nor GI injury as assessed by plasma I-FABP response. Energy intake, however, was inversely related to the I-FABP response to exercise. This finding suggests that substantial energy intakes during exercise may prevent exercise-induced GI injury as assessed by the I-FABP response. Novelty: No association between gastrointestinal complaints and gastrointestinal injury (I-FABP response) or food intake was present. There was an inverse correlation between energy intake and plasma I-FABP response, suggesting that higher energy intakes may prevent gastrointestinal injury as assessed by the I-FABP response.

Probiotic supplementation, traditionally used for the prevention or treatment of a variety of disease indications, is now recognized in a variety of population groups including athletes and those physically active for improving general health and performance. However, experimental and clinical trials with probiotics commonly suffer from design flaws and different outcome measures, making comparison and synthesis of conclusions difficult. Here we review current randomized controlled trials (RCTs) using probiotics for performance improvement, prevention of common illnesses, or general health, in a specific target population (athletes and those physically active). Future RCTs should address the key elements of (1) properly defining and characterizing a probiotic intervention, (2) study design factors, (3) study population characteristics, and (4) outcome measures, that will allow valid conclusions to be drawn. Careful evaluation and implementation of these elements should yield improved trials, which will better facilitate the generation of evidence-based probiotic supplementation recommendations for athletes and physically active individuals., Competing Interests: AM is employed by Isagenix International LLC. Isagenix was not involved in any aspect of the review. JP is a consultant for Aliment Nutrition Ltd. JT has previously received grants to evaluate the efficacy of various nutritional supplements including probiotics. FW received research funding from Royal Friesland Campina N.V., Amersfoort, the Netherlands after this review was drafted. NW has been the recipient of research from DuPont, Chr Hanson, Yakult, Probiotics Australia, UAS Laboratories, and Winclove Probiotics. CW serves on scientific advisory boards for the Wheat Foods Council, Ardent Mills, LLC, and the Hass Avocado Board Avocado Nutrition Science Advisory group. LM is on the Scientific Advisory Board for Bio-K+, Canada and on the Microbiome Advisory Board for Biocodex, France and is a paid lecturer for both companies. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Mohr, Pugh, O'Sullivan, Black, Townsend, Pyne, Wardenaar, West, Whisner and McFarland.)

Purpose: To provide a new and efficient at-the-toilet-bowl method of self-assessing urine concentration via urine color (Uc) to identify hypohydration., Methods: A large athletic population (n = 189) delivered a urine sample, then chose a color panel that was displayed on the back wall of the lavatory stall. Selection was based on duration of urine voiding time, so that for a short-duration, the lighter panel was selected; for a mid-duration, the mid color panel; and for a longer-void-duration, the darker panel was selected. Then, subjects noted if their urine was lighter than, similar to, or darker than the selected color panel. Trained investigators also rated subjects' urine samples. To assess validity of Uc classification, the outcome was compared with a urine concentration (urine specific gravity, USG, and urine osmolality) threshold indicating hypohydration., Results: Urine color was scored similarly by subjects and investigators (P = 0.99). Based on receiver operating curves (ROC), the method scored fair, i.e., the area under the curve ranging 0.73-0.82, with an accuracy of participants and investigators correctly classifying 72% and 75% urine samples compared to a USG threshold of 1.020, respectively, and 62% and 70% compared to a urine osmolality threshold of 836 mmol·kg -1 , respectively., Conclusion: This new lavatory urine color (LUC) method of scoring Uc levels to assess potential hypohydration gives results similar to those of traditional urine color charts, but it has the advantage of an immediate assessment of hydration status based on scoring urine color directly from the toilet bowl., (© 2021. Springer-Verlag GmbH Germany, part of Springer Nature.)

Abstract: Wardenaar, FC, Ortega-Santos, CP, Vento, K, Beaumont, JS, Griffin, SC, Johnston, C, and Kavouras, SA. A 5-day heat acclimation program improves heat stress indicators while maintaining exercise capacity. J Strength Cond Res 35(5): 1279-1286, 2021-This study aimed to evaluate whether a daily 60 minutes isothermic biking protocol during a 5-day period could improve physiological heat acclimation and exercise performance capacity in partially acclimated subjects. A quasi-experimental study consisted of an intervention (INT, n = 7) and control (CON, n = 7) group completing 2 12 minutes Cooper tests (pre-CT on day 1 and post-CT on day 7) and a heat stress test (HST, on day 9). INT performed additional intensive exercise 1 hour per day on days 1-5, whereas CON did not. During CTs and HST, core temperature (Tc, telemetric capsule), skin temperature (Tsk, sensors at neck, right shoulder, left hand, and right shin), and heart rate (HR, chest strap) were continuously monitored and baseline, average, peak, and increment were calculated. During the HST, the INT group showed a smaller baseline-peak Tc increment (INT 0.88 ± 0.27 vs. CON 1.64 ± 0.90° C, p = 0.02), a lower HR peak (150.2 ± 12.6 vs. 173.0 ± 16.8 b·min-1, p = 0.02), and lower Tsk peak (36.47 ± 0.62 vs. 36.54 ± 0.46° C, p = 0.04). There was a nonsignificant, but practical difference based on a moderate effect size for change in pre-CT to post-CT performance of nearly +2.7 ± 12.3% in INT and -3.0 ± 8.5% in CON (p = 0.32 and d = 0.51), and HST distance covered resulting in a nonsignificant difference of 464 ± 849 m between INT and CON (p = 0.38 and d = 0.44). In conclusion a short-term 5-day heat acclimation program including 300 minutes of extra exercise resulted in positive physiological adaptions to heat stress, as indicated by lower core temperature and HR in comparison with a control group., (Copyright © 2021 National Strength and Conditioning Association.)

Our objective was to determine self-reported accuracy of an athletic population using two different urine color (Uc) charts (8-color vs. 7-color Uc chart). After approval by the Institutional Review Board, members of an athletic population (n = 189, 20 (19-22) year old student- or tactical athletes and coaches, with n = 99 males and n = 90 females) scored their Uc using two charts. To determine the diagnostic value of Uc, results were compared with urine concentration (osmolality and urine specific gravity, USG). Uc was scored slightly darker with the 8-color vs. 7-color Uc chart (2.2 ± 1.2 vs. 2.0 ± 1.2, respectively, p < 0.001), with a moderate correlation between charts ( r = 0.76, 95% CI: 0.69-0.81). Bland-Altman analysis showed a weak reporting bias ( r = 0.15, p = 0.04). The area under the curve for correct urine sample classification ranged between 0.74 and 0.86. Higher accuracy for both methods was found when Uc scores were compared to USG over osmolality, indicated by 4.8-14.8% range in difference between methods. The optimal Uc cut-off value to assess a low vs. a high urine concentration for both Uc charts varied in this study between 1 and ≤2 while accuracy for charts was similar up to 77% when compared to USG.

Knowledge of third-party testing is important for elite athletes using nutritional supplements to reduce the chances of a positive doping incident. Therefore, we compared the self-reported knowledge and attitudes of N  = 601 Dutch Olympic status and non-Olympic status athletes toward an independent Dutch third-party tested system (NZVT) for purchasing nutritional supplements (NSs). Most of the athletes believed that contaminated NSs could lead to a positive doping test (68.0%), and found it unacceptable to use a contaminated NS as a result of incomplete labeling (87.8%). More Olympic status athletes were familiar with the NZVT system (71.1%) than non-Olympic status athletes (24.5%, p  < 0.001). Of the athletes knowing about NZVT, Olympic status athletes reported more frequently using the NZVT than non-Olympic athletes (81.7% vs. 50.0%, p  < 0.001). Apart from status, more females were familiar with and used the NZVT system for purchasing NSs than males, p  < 0.01. In conclusion, many athletes were not familiar with nor used the preferred third-party testing supplement system in the Netherlands when purchasing NSs. While doping warnings and regulations have been in place, considering the risk of unintentional doping use for over two decades, the knowledge of Olympic status and non-Olympic status high-level athletes could still be improved, as many are not reporting the use of third-party testing systems.

Dietary supplements, sports foods, and ergogenic supplements are consumed to increase performance, recovery, and health, but risk contamination with illegal substances. Third-party testing programs may assist in regulating the purity and safety of supplements, yet athletes' attitudes and use of such programs are not widely reported. This study examined nutritional supplement knowledge, attitudes, and use, as well as the purchase of third-party tested supplements among university student-athletes ( N = 138). Knowledge of nutritional supplements yielded a median and (IQR) score of 25% (17 to 42%). Sixteen percent of student-athletes said they were knowledgeable about supplements and their effects, p < 0.001. All athletes stated they used a dietary supplement or sports food at least once within the last 12 months, and 77% consumed at least one "claimed to be" ergogenic supplement. Sixty-six percent of student-athletes purchased nutritional supplements not provided by the athletic department. Females athletes were more likely to consume a combination of vitamins and single minerals, a larger variety of sports foods, exotic berries, herbs, maca root powder, ribose, ephedra, colostrum, and hydroxy-methyl-buterate (HMB) than males. Over 90% believed it was essential to know if a supplement was third-party tested. However, only 57% stated the supplements bought were third-party tested. No sex differences were found for nutritional supplement knowledge, attitudes, and use of third-party testing programs. Our results indicate a need to improve student-athletes' attitudes toward and knowledge of nutritional supplements, and the initiation of programs to assist in the choosing and consuming of third-party tested supplements., (Copyright © 2020 Vento and Wardenaar.)

This study investigated the real-time progression of heat strain in mountain hikers during time trials (TT). Participants ( n = 12; 7M/5F; age 21.6 ± 2.47) attempted to climb Tempe Butte (~1.1 mi) four times in HOT and MOD trials (wet bulb globe temperature 31.6 °C vs. 19.0 °C). Performance, physiological outcomes, and fluid intake behavior were measured in real-time. Hot conditions significantly impaired hiking TT performance by 11%, reduced aerobic capacity by 7%, increased peak rate of perceived exertion (RPE) by 19%, and elevated core temperature (T c ) by 0.7 °C compared to MOD (all p < 0.03). Less-aerobically-fit participants were most negatively-affected by heat stress. Based on sweat lost, participants in HOT required 2.26 ± 0.91 L of fluids, brought 1.52 ± 0.83 L, and consumed 1.54 ± 0.49 L, losing an average of 1.1% ± 1.0%BM. Participants in MOD required 1.28 ± 0.39 L of fluids, brought 1.57 ± 1.09 L, and consumed 0.79 ± 0.57 L, losing an average of 1.0% ± 0.8%BM. Morning-after urine specific gravity (USG) values revealed 75% of hikers were hypohydrated (USG ≥ 1.020) after HOT; 67% after MOD. Heat stress impairs hiking TT performance while increasing RPE and T c . Fitter participants showed less performance and physiological impairment from heat stress. Although hikers in both conditions lost similar body weight, hikers were limited in HOT by fluid availability, whereas in MOD, fluid was available and dehydration was voluntary.

Information about the accuracy of self-reported food and fluid intake during competitions is scarce. The objective of this study was to validate a previously developed food and fluid exercise questionnaire (FFEQ) against direct observations made during competitions in athletes. Fifty-eight recreational endurance athletes participating in four different running events and one cross duathlon in the Netherlands between 2015 and 2017 were recruited. The FFEQ overestimated the median energy and carbohydrate intake by 27.6 kcal/h (20.6%) and 9.25 g/h (30.8%) ( p < 0.001), respectively, compared to direct observation. Reporting bias (i.e., correlation between the difference between methods and average of both methods) increased with a higher energy ( r : 0.41, p < 0.01) and carbohydrate intake ( r : 0.44, p < 0.01). No statistically significant difference was found between FFEQ-reported fluid intake per hour and observations (median difference: -2.93 mL, -1.1%; p = 0.48) and no fluid reporting bias was identified ( r : 0.23, p = 0.08). FFEQ-reported energy ( r : 0.74), carbohydrate (r: 0.74), and fluid (r: 0.85) intake was strongly correlated with the observed intake (all p -values < 0.001). In conclusion, the FFEQ accurately estimates the fluid intake on a group level during competitions in recreational athletes. Even though FFEQ overestimates the energy and carbohydrate intake, it is still a useful tool for ranking individuals based on their intake.

Introduction: Recently, it has been speculated that protein supplementation may further augment the adaptations to chronic endurance exercise training. We assessed the effect of protein supplementation during chronic endurance exercise training on whole-body oxidative capacity (V˙O2max) and endurance exercise performance., Methods: In this double-blind, randomized, parallel placebo-controlled trial, 60 recreationally active males (age, 27 ± 6 yr; body mass index, 23.8 ± 2.6 kg·m; V˙O2max, 47 ± 6 mL·min·kg) were subjected to 12 wk of triweekly endurance exercise training. After each session and each night before sleep, participants ingested either a protein supplement (PRO; 28.7 g casein protein) or an isoenergetic carbohydrate placebo (PLA). Before and after the 12 wk of training, V˙O2max and endurance exercise performance (~10-km time trial) were assessed on a cycle ergometer. Muscular endurance (total workload achieved during 30 reciprocal isokinetic contractions) was assessed by isokinetic dynamometry and body composition by dual-energy x-ray absorptiometry. Mixed-model ANOVA was applied to assess whether training adaptations differed between groups., Results: Endurance exercise training induced an 11% ± 6% increase in V˙O2max (time effect, P < 0.0001), with no differences between groups (PRO, 48 ± 6 to 53 ± 7 mL·min·kg; PLA, 46 ± 5 to 51 ± 6 mL·min·kg; time-treatment interaction, P = 0.50). Time to complete the time trial was reduced by 14% ± 7% (time effect, P < 0.0001), with no differences between groups (time-treatment interaction, P = 0.15). Muscular endurance increased by 6% ± 7% (time effect, P < 0.0001), with no differences between groups (time-treatment interaction, P = 0.84). Leg lean mass showed an increase after training (P < 0.0001), which tended to be greater in PRO compared with PLA (0.5 ± 0.7 vs 0.2 ± 0.6 kg, respectively; time-treatment interaction, P = 0.073)., Conclusion: Protein supplementation after exercise and before sleep does not further augment the gains in whole-body oxidative capacity and endurance exercise performance after chronic endurance exercise training in recreationally active, healthy young males.

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.

This study investigated the differences in gastrointestinal (GI) and exercise related complaints between groups of runners competing at different distances using web-based questionnaires. Total (severe) complaints were reported by 89.3% (49.7%) of the runners during the race vs. 70.6% (29.4%) after the race. Significant differences between groups were described for marathon (n = 98) and 60 km (n = 43) runners. During competition, runners reported the urge to urinate (47.7%), muscle cramps (43.6%) and belching (43.6%). The prevalence of bloating, flatulence, side ache and dizziness differed between distances ( p < 0.02). There were small to moderate negative correlations between food and fluid intake and GI complaints. After competition (12 h), 70.6% of participants reported complaints, with muscle cramps (47.6%), flatulence (19.0%) and bloating (12.7%) being the most prevalent. Prevalence of belching, nausea, stomach cramps and muscle cramps differed between race distances ( p < 0.04). There were small to high positive correlations between complaints during and after competition ( p < 0.05). In conclusion, runners of all distances reported a high prevalence of GI and other exercise related complaints. There were some small differences in reporting type and severity of complaints between distances. Results showed small to strong correlations between complaints during and after competition and with nutrient intake, without a clear similar pattern for all distances.

The aim of the present case study was to use real-time observations to investigate ultramarathon runners' timing of food and fluid intake per 15 km and per hour, and total bodyweight loss due to dehydration. The study included 5 male ultramarathon runners observed during a 120 km race. The research team members followed on a bicycle and continuously observed their dietary intake using action cameras. Hourly carbohydrate intake ranged between 22.1 and 62.6 g/h, and fluid intake varied between 260 and 603 mL/h. These numbers remained relatively stable over the course of the ultra-endurance marathon. Runners consumed food and fluid on average 3-6 times per 15 km. Runners achieved a higher total carbohydrate consumption in the second half of the race ( p = 0.043), but no higher fluid intake ( p = 0.08). Energy gels contributed the most to the total average carbohydrate intake (40.2 ± 25.7%). Post-race weight was 3.6 ± 2.3% (range 0.3-5.7%) lower than pre-race weight, revealing a non-significant ( p = 0.08) but practical relevant difference. In conclusion, runners were able to maintain a constant timing of food and fluid intake during competition but adjusted their food choices in the second half of the race. The large variation in fluid and carbohydrate intake indicate that recommendations need to be individualized to further optimize personal intakes.

Dietary protein intake should be optimized in all athletes to ensure proper recovery and enhance the skeletal muscle adaptive response to exercise training. In addition to total protein intake, the use of specific proteincontaining food sources and the distribution of protein throughout the day are relevant for optimizing protein intake in athletes. In the present study, we examined the daily intake and distribution of various proteincontaining food sources in a large cohort of strength, endurance and team-sport athletes. Well-trained male (n=327) and female (n=226) athletes completed multiple web-based 24-hr dietary recalls over a 2-4 wk period. Total energy intake, the contribution of animal- and plant-based proteins to daily protein intake, and protein intake at six eating moments were determined. Daily protein intake averaged 108±33 and 90±24 g in men and women, respectively, which corresponded to relative intakes of 1.5±0.4 and 1.4±0.4 g/kg. Dietary protein intake was correlated with total energy intake in strength (r=0.71, p <.001), endurance (r=0.79, p <.001) and team-sport (r=0.77, p <.001) athletes. Animal and plant-based sources of protein intake was 57% and 43%, respectively. The distribution of protein intake was 19% (19±8 g) at breakfast, 24% (25±13 g) at lunch and 38% (38±15 g) at dinner. Protein intake was below the recommended 20 g for 58% of athletes at breakfast, 36% at lunch and 8% at dinner. In summary, this survey of athletes revealed they habitually consume > 1.2 g protein/kg/d, but the distribution throughout the day may be suboptimal to maximize the skeletal muscle adaptive response to training.

Although beetroot juice, as a nitrate carrier, is a popular ergogenic supplement among athletes, nitrate is consumed through the regular diet as well. We aimed to assess the habitual dietary nitrate intake and identify the main contributing food sources in a large group of highly trained athletes. Dutch highly trained athletes (226 women and 327 men) completed 2-4 web-based 24-hr dietary recalls and questionnaires within a 2- to 4-week period. The nitrate content of food products and food groups was determined systematically based on values found in regulatory reports and scientific literature. These were then used to calculate each athlete's dietary nitrate intake from the web-based recalls. The median[IQR] habitual nitrate intake was 106[75-170] mg/d (range 19-525 mg/d). Nitrate intake correlated with energy intake (ρ = 0.28, p < .001), and strongly correlated with vegetable intake (ρ = 0.78, p < .001). In accordance, most of the dietary nitrate was consumed through vegetables, potatoes and fruit, accounting for 74% of total nitrate intake, with lettuce and spinach contributing most. When corrected for energy intake, nitrate intake was substantially higher in female vs male athletes (12.8[9.2-20.0] vs 9.4[6.2-13.8] mg/MJ; p < .001). This difference was attributed to the higher vegetable intake in female vs male athletes (150[88-236] vs 114[61-183] g/d; p < .001). In conclusion, median daily intake of dietary nitrate in highly trained athletes was 106 mg, with large interindividual variation. Dietary nitrate intake was strongly associated with the intake of vegetables. Increasing the intake of nitrate-rich vegetables in the diet might serve as an alternative strategy for nitrate supplementation.

The use of nutritional supplements is highly prevalent among athletes. In this cross-sectional study, we assessed the prevalence of nutritional supplement use by a large group of Dutch competitive athletes in relation to dietary counseling. A total of 778 athletes (407 males and 371 females) completed a web-based questionnaire about the use of nutritional supplements. Log-binomial regression models were applied to estimate crude and adjusted prevalence ratios (PR) for the use of individual nutritional supplements in athletes receiving dietary counseling as compared with athletes not receiving dietary counseling. Of the athletes, 97.2% had used nutritional supplements at some time during their sports career, whereas 84.7% indicated having used supplements during the last 4 weeks. The top ranked supplements used over the last 4 weeks from dietary supplements, sport nutrition products and ergogenic supplements were multivitamin and mineral preparations (42.9%), isotonic sports drinks (44.1%) and caffeine (13.0%). After adjustment for elite status, age, and weekly exercise duration, dietary counseling was associated with a higher prevalence of the use of vitamin D, recovery drinks, energy bars, isotonic drinks with protein, dextrose, beta-alanine, and sodium bicarbonate. In contrast, dietary counseling was inversely associated with the use of combivitamins, calcium, vitamin E, vitamin B2, retinol, energy drinks and BCAA and other amino acids. In conclusion, almost all athletes had used nutritional supplements at some time during their athletic career. Receiving dietary counseling seemed to result in better-informed choices with respect to the use of nutritional supplements related to performance, recovery, and health.

Purpose: The effects of moderate beer consumption after physical activity on rehydration and fluid balance are not completely clear. Therefore, in this study, we investigated the effect of beer consumption, with varying alcohol content, on fluid balance after exercise-induced dehydration., Methods: Eleven healthy males were included in this cross over study (age 24.5 ± 4.7 years, body weight 75.4 ± 3.3 kg, VO 2max 58.3 ± 6.4 mL kg min -1 ). Subjects exercised on a cycle ergometer for 45 min at 60% of their maximal power output ( W max ) until mild dehydration (1% body mass loss). Thereafter, in random order, one of five experimental beverages was consumed, in an amount equal to 100% of their sweat loss: non-alcoholic beer (0.0%), low-alcohol beer (2.0%), full-strength beer (5.0%), an isotonic sports drink, and water. Fluid balance was assessed up till 5 h after rehydration., Results: After 1 h, urine production was significantly higher for 5% beer compared to the isotonic sports drink (299 ± 143 vs. 105 ± 67 mL; p  < 0.01). At the end of the 5-h observation period, net fluid balance (NFB) was negative for all conditions ( p  = 0.681), with the poorest fluid retention percentage for 5% beer (21% fluid retention) and the best percentage for the isotonic sports drink (42%). Non-alcoholic beer, low-alcoholic beer, and water resulted in fluid retention of 36, 36, and 34%, respectively ( p  = 0.460)., Conclusion: There was no difference in NFB between the different beverages. Only a short-lived difference between full-strength beer and the isotonic sports drink in urine output and NFB was observed after mild exercise-induced dehydration. Fluid replacement - either in the form of non-alcoholic beer, low-alcoholic beer, full-strength beer, water, or an isotonic sports drink of 100% of body mass loss was not sufficient to achieve full rehydration. The combination of a moderate amount of beer, with varying alcohol content, enough water or electrolyte- and carbohydrate beverages, and salty foods might improve rehydration, but more research is needed.

The nutritional status of elite soccer players across match, postmatch, training and rest days has not been defined. Recent evidence suggests the pattern of dietary protein intake impacts the daytime turnover of muscle proteins and, as such, influences muscle recovery. We assessed the nutritional status and daytime pattern of protein intake in senior professional and elite youth soccer players and compared findings against published recommendations. Fourteen senior professional (SP) and 15 youth elite (YP) soccer players from the Dutch premier division completed nutritional assessments using a 24-hr web-based recall method. Recall days consisted of a match, postmatch, rest, and training day. Daily energy intake over the 4-day period was similar between SP (2988 ± 583 kcal/day) and YP (2938 ± 465 kcal/day; p = .800). Carbohydrate intake over the combined 4-day period was lower in SP (4.7 ± 0.7 g·kg-1 BM·day-1) vs. YP (6.0 ± 1.5 g·kg-1 BM·day-1, p = .006) and SP failed to meet recommended carbohydrate intakes on match and training days. Conversely, recommended protein intakes were met for SP (1.9 ± 0.3 g·kg-1 BM·day-1) and YP (1.7 ± 0.4 g·kg-1 BM·day-1), with no differences between groups (p = .286). Accordingly, both groups met or exceeded recommended daily protein intakes on individual match, postmatch, rest and training days. A similar "balanced" daytime pattern of protein intake was observed in SP and YP. To conclude, SP increased protein intake on match and training days to a greater extent than YP, however at the expense of carbohydrate intake. The daytime distribution of protein intake for YP and SP aligned with current recommendations of a balanced protein meal pattern.

Information on dietary composition is vitally important for elite athletes to optimise their performance and recovery, which requires valid tools. The aim of the present study was to investigate the validity of assessing protein intake using three web-based 24-h recalls and questionnaires, by comparing these with three urinary N excretions on the same day. A total of forty-seven Dutch elite top athletes, both disabled and non-disabled, aged between 18 and 35 years, with a BMI of 17·5-31 kg/m2, exercising >12 h/week were recruited. Estimated mean dietary protein intake was 109·6 (sd 33·0) g/d by recalls and questionnaires v. 141·3 (sd 38·2) g/d based on N excretions in urine; the difference was 25·5 (sd 21·3) % between the methods (P<0·05). We found a reasonably good association between methods for protein intake of 0·65 (95 % CI 0·45, 0·79). On an individual level, under-reporting was larger with higher protein intakes than with lower intakes. No significant differences were found in reporting absolute differences between subcategories (sex, under-reporting, BMI, collection of recalls within a certain amount of time and using protein supplements or not). In conclusion, combined, multiple, 24-h recalls and questionnaires underestimated protein intake in these young elite athletes more than that reported for non-athlete populations. The method proved to be suitable for ranking athletes according to their protein intake as needed in epidemiological studies. On an individual level, the magnitude of underestimation was about equal for all athletes except for those with very high protein intakes.

Purpose: The objective of this study was to investigate whether ultramarathon runners were able to meet nutrition recommendations during a training period and on a competition day., Methods: In preparation for a 60 or 120 km ultramarathon covering a varied terrain, male and female ultramarathon runners (n = 68, age 46.5 ± 7.1 y) reported habitual dietary intake during three independent days using a web-based 24-hr recall and questionnaires. The diet was assessed using probability of inadequacy or by qualitative evaluation using reference dietary intakes or sports nutrition recommendations. A small group of 120 km runners (n = 4) was observed continuously during the race. After the race, 60 km runners (n = 41) received a questionnaire to assess dietary intake and gastrointestinal (GI) distress on the race day. Spearman rank correlation coefficients (r) were applied to investigate the association between intake and general GI distress symptoms., Results: In men and women, habitual mean carbohydrate (CHO) intake was lower than recommended, as was mean protein intake by women. CHO intake during the race was <60 g/h in 75% of the athletes. A large variation of nutrient and fluid intake was seen. GI distress during the race was reported in 82% of the runners; severe GI distress was low. In general, moderate, mostly negative, correlations with nutrient intake were seen for GI distress., Conclusion: Sports nutrition recommendations for the habitual diet were not achieved. During a competition day, a large variation was found in nutrient intake; this may be related to a high incidence of GI distress.