Vegetarian, Gluten-Free, and Energy Restricted Diets in Female Athletes

Body Appreciation is Associated with Emotional Eating in Turkish Female Athletes

It is known that female athletes are at risk for eating disorders. It is thought that factors such as pressure and stress experienced by professional athletes may affect emotional eating and body appreciation. In this context, the aim of this study was to evaluate the emotional eating and body appreciation of professional Turkish female athletes. A total of 265 professional female athletes were categorized according to their sport types and nationality. Emotional eating was found to be higher and body appreciation to be lower in athletes competing at the national level. The results of the hierarchical regression analysis, which included variables such as age, body mass index, professional sports background, national level, and sport type show that the most effective factor in explaining emotional eating in professional female athletes is body appreciation. The present study findings support that professional female athletes are at risk in terms of emotional eating and body appreciation. In addition, emotional eating scores were found to be higher and body appreciation scores were lower in national athletes. Psychological factors such as intense stress and pressure have an impact on the eating behavior and body appreciation of national athletes. These results suggest that athletes should be evaluated by nutritionists, doctors, and psychologists from a multidisciplinary perspective.

Return to Running for Postpartum Elite and Subelite Athletes

CONTEXT

There is little evidence to guide elite athletes who desire returning to competition after giving birth to a child. Ultimately, this can result in decreased performance and increased risk of injury. This paper addresses aspects that must be considered when building and monitoring a return to running program for a postpartum elite or subelite athlete, including pelvic floor and core stability, progressive reloading of the musculoskeletal system, monitoring of nutritional parameters, and considerations for lactation.

EVIDENCE ACQUISITION

PubMed and CINAHL (Cumulative Index for Nursing and Allied Health Literature) were searched with the following search strategy: (extreme sports OR elite athletes OR running OR exercise) AND (breastfeeding OR lactation OR bone density OR fetal weight OR gestational weight gain OR postpartum or post-partum OR postnatal OR post-natal OR pregnancy OR childbirth). The following information is based on best available evidence and clinical experience.

STUDY DESIGN

Clinical review.

LEVEL OF EVIDENCE

Level 4.

RESULTS

Due to the interplay between cardiovascular fitness, postpartum nutrition, lactation, and progressive reloading of the muscular and skeletal system, we propose a multimodal, multidisciplinary approach to safely and successfully allow an athlete to return to an elite level of competition.

CONCLUSION

Return to running in the postpartum period is a highly individualized process that benefits from multidisciplinary, individualized care. This includes monitoring of nutrition, core and pelvic floor function, bone reloading, muscle and tendon reloading, and breastfeeding care when applicable.

STRENGH OF RECOMMENDATION TAXONOMY (SORT)

C.

Seasonal health tracking of Australian Football League Women's athletes

BACKGROUND

Studies evaluating the dietary intake of Australian Football League Women's (AFLW) athletes are few and limited to the preseason. This prospective observational study aims to evaluate seasonal changes in dietary intake and health parameters of professional AFLW athletes.

METHODOLOGY

Dietary intake (3-day weighed food records), body composition (bioelectrical impedance analysis, skinfolds), physical performance (global positioning system, GPS), and iron status (fasted blood sample) were assessed in 19 athletes (24 ± 5 years, 170 ± 6 cm, 22.8 ± 2.1 kg/m2) at three timepoints: start of preseason, end of preseason, and end of competition season. Sociodemographic information, sports nutrition knowledge (SNK), and risk of low energy availability (LEA) questionnaires were completed at the start of preseason.

RESULTS

Mean daily energy and carbohydrate (CHO) intakes were lower than recommendations across all seasons (p < 0.05). Mean daily CHO intake was highest at start of preseason (3.6 g/kg/day), decreased during preseason (3.1 g/day) and remained low during competition (3.2 g/day); >80% of players did not meet minimum recommendations at each timepoint (all, p < 0.05). The sum of seven skinfolds and fat mass (%) decreased during preseason (both, p < 0.05). Serum iron fell within recommended ranges for 95% of athletes at all timepoints. The total distance (m) and number of Very High Intensity (>21 km/h) efforts significantly increased across preseason and decreased during competition (all, p < 0.05). Nutrition knowledge was 'poor', and 42% of athletes were at risk of LEA.

CONCLUSIONS

AFLW athletes do not meet energy and carbohydrate requirements across the preseason and competition seasons, which may impact health and performance if deficits are sustained.

Body composition as a marker of performance and health in military personnel

Introduction

Body composition standards are set to ensure operational readiness in active-duty military personnel. To meet body composition standards, some individuals, however, may engage in unhealthy weight control behaviors (i.e., weight cycling and disordered eating). The objectives of this review are to: (1) evaluate the evidence regarding body composition and the associations to physical and military specific performance; (2) discuss body composition and potential health consequences; and (3) examine the evidence of weight cycling and disordered eating behaviors in military personnel for weight control.

Methods

A systematic search to identify peer-reviewed research articles was conducted in PubMed on 2/20/2023 using Medical Subject Headings (MeSH) including but not limited to "Military Personnel", "Tactical Athlete", "Weight Loss", "Body Composition", and "Weight Cycling".

Results

A total of 225 research articles were identified. The list was narrowed down to articles from the last 20 years (2003-2023) in military personnel. Only studies in which percent body fat was directly measured were included resulting in 17 research articles for this review.

Discussion

Evidence-based research is limited on the relationship between body composition and operational readiness. Weight cycling and disordered eating behaviors also has been reported for weight control, yet additional research is needed. Specifically, future research should focus on female service members, racial and ethnic differences, age, and postpartum status and include other service branches (i.e., Air Force and Navy). A comprehensive survey on weight cycling, disordered eating, and weight management would be valuable to determine the prevalence and extent of this issue. This information along with performance data would guide policy makers on the relevance and appropriateness of existing body composition standards.

Methodology for studying Relative Energy Deficiency in Sport (REDs): a narrative review by a subgroup of the International Olympic Committee (IOC) consensus on REDs

In the past decade, the study of relationships among nutrition, exercise and the effects on health and athletic performance, has substantially increased. The 2014 introduction of Relative Energy Deficiency in Sport (REDs) prompted sports scientists and clinicians to investigate these relationships in more populations and with more outcomes than had been previously pursued in mostly white, adolescent or young adult, female athletes. Much of the existing physiology and concepts, however, are either based on or extrapolated from limited studies, and the comparison of studies is hindered by the lack of standardised protocols. In this review, we have evaluated and outlined current best practice methodologies to study REDs in an attempt to guide future research.This includes an agreement on the definition of key terms, a summary of study designs with appropriate applications, descriptions of best practices for blood collection and assessment and a description of methods used to assess specific REDs sequelae, stratified as either Preferred, Used and Recommended or Potential Researchers can use the compiled information herein when planning studies to more consistently select the proper tools to investigate their domain of interest. Thus, the goal of this review is to standardise REDs research methods to strengthen future studies and improve REDs prevention, diagnosis and care.

The Low Energy Availability in Females Questionnaire (LEAF-Q) as a Useful Tool to Identify Female Triathletes at Risk for Menstrual Disorders Related to Low Energy Availability

BACKGROUND

Nutrition in sport is a priority; it is the basis for maintaining optimal health and a prerequisite for the high performance necessary for competitions. The aim of this study was to assess low energy availability and its possible consequences among female triathletes by using the Low Energy Availability in Females Questionnaire (LEAF-Q).

METHODS

The study involved 30 female triathetes. The LEAF-Q was used in the study. An analysis of the body composition was carried out with the seca device mBCA 515 medical Body Composition Analyzer.

RESULTS

Of the 30 female triathletes studied, 23.3% had a monthly cycle disorder, defined as an amenorrhea state for more than 90 days. No differences were found in injury rates or training days lost to injury due to menstrual disturbances. Menstruation changes were significantly greater due to increases in exercise intensity, frequency, and duration in the group experiencing menstrual disturbances (85.7 [95% CIs: 42.1-99.6] vs. 8.7 [95% CIs: 1.1-28.0]). The menstrual disorder group had a greater incidence of their periods stopping for more than 3 months than the group without menstrual disturbances.

CONCLUSIONS

The female triathletes did not show abnormalities in body weight or composition, and these were not related to the incidence of menstrual disturbances. However, 20% of the triathletes either had, at the time of the study, or had had in the past monthly cycle disorders that could indicate an immediate risk of low energy availability. The LEAF-Q identified 10% of the triathletes as at risk (score > 8) of low energy availability and the physiological and performance consequences related to relative energy deficiency in sports (RED-S).

Factors influencing performance and injury risk in elite female Gaelic team sport players and future research directions: a narrative review

Background

Sports science research in elite female Gaelic team sports has increased in recent years, but still a large disparity exists between the volume of studies involving male and female players. As a consequence of this, it is difficult for practitioners to develop an evidence-based approach when working with female players.

Main body

In this review, we discuss the current research available in elite female Gaelic team sports with focus on seven specific areas including physical and physiological demands, anthropometric and performance characteristics, injury risk, nutritional considerations, and female physiology. There appears to be unique physical demands data in match play across positions in Camogie, however, there is currently no comparative data available in ladies Gaelic football. Similarly, there is no research available on the physiological demands of both elite female Gaelic team sports. According to existing literature, performance characteristics such as speed and power are lower in this population compared to other elite female team sports. Although data is limited, the anthropometric characteristics of elite female Gaelic team sport players appear homogenous with some positional differences observed at a sub-elite level. Previous research has demonstrated a high prevalence of lower limb injuries in female elite Gaelic team sports and the provision of quality, evidence-based strength & conditioning could help mitigate these injury risks. Female Gaelic team sport players have been shown to have poor nutrition knowledge and inadequate intakes of micronutrients. Finally, although menstrual cycle phase and oral contraceptives have been shown to influence performance in other female intermittent sports, to date there has not been any research carried out in elite female Gaelic team sport players.

Conclusions

It is evident that limited research has been carried out on elite female Gaelic sport players. More up-to-date, high-quality investigations are needed to address the research gaps, which in turn should enable practitioners in the field to apply sound, evidence-based practice/theory when working with this population.

The impact of dieting culture is different between sexes in endurance athletes: a cross-sectional analysis

Background

Frequent dieting is common in athletes attempting to achieve a body composition perceived to improve performance. Excessive dieting may indicate disordered eating (DE) behaviors and can result in clinical eating disorders. However, the current nutrition patterns that underly dieting culture are underexplored in endurance athletes. Therefore, the purpose of this study was to identify the sex differences in nutrition patterns among a group of endurance athletes.

Methods

Two-hundred and thirty-one endurance athletes (females = 124) completed a questionnaire regarding their dieting patterns and associated variables.

Results

The majority of athletes did not follow a planned diet (70.1%). For endurance athletes on planned diets (n = 69), males were more likely follow a balanced diet (p = 0.048) and females were more likely to follow a plant-based diet (p = 0.021). Female endurance athletes not on a planned diet (n = 162) were more likely to have attempted at least one diet (p < 0.001). Male athletes attempted 2.0 ± 1.3 different diets on average compared to 3.0 ± 2.0 for females (p = 0.002). Female athletes were more likely to attempt ≥ three diets (p = 0.022). The most common diet attempts included carbohydrate/energy restrictive, plant-based, and elimination diets. Females were more likely to attempt ketogenic (p = 0.047), low-carbohydrate (p = 0.002), and energy restricted diets (p = 0.010). Females made up the entirety of those who attempted gluten-/dairy-free diets (F = 22.0%, M = 0.0%).

Conclusions

Being a female athlete is a major determinant of higher dieting frequency and continual implementation of popular restrictive dietary interventions. Sports dietitians and coaches should prospectively assess eating behavior and provide appropriate programming, education, and monitoring of female endurance athletes.

Dietary Iron and the Elite Dancer

Dancers are an athlete population at high risk of developing iron deficiency (ID). The aesthetic nature of the discipline means dancers potentially utilise dietary restriction to meet physique goals. In combination with high training demands, this means dancers are susceptible to problems related to low energy availability (LEA), which impacts nutrient intake. In the presence of LEA, ID is common because of a reduced mineral content within the low energy diet. Left untreated, ID becomes an issue that results in fatigue, reduced aerobic work capacity, and ultimately, iron deficient anaemia (IDA). Such progression can be detrimental to a dancer’s capacity given the physically demanding nature of training, rehearsal, and performances. Previous literature has focused on the manifestation and treatment of ID primarily in the context of endurance athletes; however, a dance-specific context addressing the interplay between dance training and performance, LEA and ID is essential for practitioners working in this space. By consolidating findings from identified studies of dancers and other relevant athlete groups, this review explores causal factors of ID and potential treatment strategies for dancers to optimise absorption from an oral iron supplementation regime to adequately support health and performance.

Benefits of a plant-based diet and considerations for the athlete

Individuals may opt to follow a plant-based diet for a variety of reasons, such as religious practices, health benefits or concerns for animal or environmental welfare. Such diets offer a broad spectrum of health benefits including aiding in the prevention and management of chronic diseases. In addition to health benefits, a plant-based diet may provide performance-enhancing effects for various types of exercise due to high carbohydrate levels and the high concentration of antioxidants and phytochemicals found in a plant-based diet. However, some plant-based foods also contain anti-nutrional factors, such as phytate and tannins, which decrease the bioavailability of key nutrients, such as iron, zinc, and protein. Thus, plant-based diets must be carefully planned to ensure adequate intake and absorption of energy and all essential nutrients. The current narrative review summarizes the current state of the research concerning the implications of a plant-based diet for health and exercise performance. It also outlines strategies to enhance the bioavailability of nutrients, sources of hard-to-get nutrients, and sport supplements that could interest plant-based athletes.

The Safe and Effective Use of Plant-Based Diets with Guidelines for Health Professionals

Plant-based diets, defined here as including both vegan and lacto-ovo-vegetarian diets, are growing in popularity throughout the Western world for various reasons, including concerns for human health and the health of the planet. Plant-based diets are more environmentally sustainable than meat-based diets and have a reduced environmental impact, including producing lower levels of greenhouse gas emissions. Dietary guidelines are normally formulated to enhance the health of society, reduce the risk of chronic diseases, and prevent nutritional deficiencies. We reviewed the scientific data on plant-based diets to summarize their preventative and therapeutic role in cardiovascular disease, cancer, diabetes, obesity, and osteoporosis. Consuming plant-based diets is safe and effective for all stages of the life cycle, from pregnancy and lactation, to childhood, to old age. Plant-based diets, which are high in fiber and polyphenolics, are also associated with a diverse gut microbiota, producing metabolites that have anti-inflammatory functions that may help manage disease processes. Concerns about the adequate intake of a number of nutrients, including vitamin B12, calcium, vitamin D, iron, zinc, and omega-3 fats, are discussed. The use of fortified foods and/or supplements as well as appropriate food choices are outlined for each nutrient. Finally, guidelines are suggested for health professionals working with clients consuming plant-based diets.

Anemia in Sports: A Narrative Review

Recent years have brought about new understandings regarding the pathogenesis of anemia in sports. From hemodilution and redistribution considered to contribute to the so-called “sports anemia” to iron deficiency caused by increased demands, dietary restrictions, decreased absorption, increased losses, hemolysis, and sequestration, to genetic determinants of different types of anemia (some related to sport), the anemia in athletes deserves a careful and multifactorial approach. Dietary factors that reduce iron absorption (e.g., phytate, polyphenols) and that augment iron’s bioavailability (e.g., ascorbic acid) should be considered. Celiac disease, more prevalent in female athletes, may underlie an unexplained iron deficiency anemia. Iron loss during exercise occurs in several ways: sweating, hematuria, gastrointestinal bleeding, inflammation, and intravascular and extravascular hemolysis. From a practical point of view, assessing iron status, especially in the athletes at risk for iron deficiency (females, adolescents, in sports with dietary restrictions, etc.), may improve the iron balance and possibly the performance. Hemoglobin and serum ferritin are measures that are easily employable for the evaluation of patients’ iron status. Cutoff values should probably be further assessed with respect to the sex, age, and type of sport. A healthy gut microbiome influences the iron status. Athletes at risk of iron deficiency should perform non-weight-bearing, low-intensity sports to avoid inducing hemolysis.

Markers of Low-Iron Status Are Associated with Female Athlete Triad Risk Factors

PURPOSE

The Female Athlete Triad (Triad) is common in female athletes. The Triad is caused by low-energy availability (EA), which is often difficult to measure and has been postulated to be associated with low-iron status. Here, we explore whether markers of low-iron status may be associated with indicators of low EA including Triad risk factors.

METHODS

A total of 239 female National Collegiate Athletic Association Division I athletes completed preparticipation examinations that included Triad risk factors, medication/supplement use, diagnosis of anemia, and elected to complete dual-energy x-ray absorptiometry scan to measure bone mineral density. The association of markers of low iron (defined as self-report of iron supplementation and/or history of anemia) with each component of the Triad risk assessment score was assessed by stratifying low-iron status across different levels of Triad risk category. Differences across iron status groups were assessed using Fisher exact testing.

RESULTS

Every component of the Triad risk assessment score excluding delayed menarche was associated with low-iron status. The proportion of women who reported low iron was 11.5% in the low-risk EA group compared with 50% in the moderate-risk and 66.7% in the high-risk EA groups (P = 0.02); respectively. These numbers were 11.6%, 25.0%, and 66.7% (P = 0.02) for body mass index; 9.7%, 16.7%, and 25.0% (P < 0.05) for oligomenorrhea; 10.3%, 45.5%, and 50.0% (P < 0.01) for bone mineral density; and 10.4%, 20.8%, and 30.8% (P = 0.03) for history of stress reaction or fracture. Lean/endurance athletes were more likely to have low-iron status than other athletes (15.5% vs 3.4%, P = 0.02).

CONCLUSIONS

Markers for low-iron status were associated with Triad risk factors. Our study suggests that female athletes with a history of anemia or iron supplementation may require further screening for low EA.

Specific dietary practices in female athletes and their association with positive screening for disordered eating

BACKGROUND

To determine if following specific diets was associated with reporting behaviors that are consistent with disordered eating compared to non-diet-adherent athletes. We hypothesized that athletes adhering to specific diets were more likely to report disordered eating than those not following a diet.

METHODS

One thousand female athletes (15-30 years) completed a comprehensive survey about athletic health and wellness. Athletes were asked to specify their diet and completed 3 eating disorder screening tools: the Brief Eating Disorder in Athletes Questionnaire, the Eating Disorder Screen for Primary Care, and self-reported current or past history of eating disorder or disordered eating. Descriptive statistics were calculated for all study measures and chi-squared tests assessed relationships between athletes' dietary practices and their responses to eating disorder screening tools. Statistical significance was defined as p < 0.05.

RESULTS

Two hundred thirty-four of 1000 female athletes reported adherence to specific diets. 69 of the 234 diet-adhering athletes (29.5%) were excluded due to medically-indicated dietary practices or vague dietary descriptions. Of the 165 diet-adherent athletes, 113 (68.5%) screened positively to ≥1 of the 3 eating disorder screening tools. Specifically, athletes practicing a low-carbohydrate diet were more likely to report disordered eating vs. athletes without dietary restrictions (80% vs. 41.8%; p < 0.0001).

CONCLUSION

Specific diet adherence in female athletes may be associated with reporting behaviors that are consistent with disordered eating. Health practitioners should consider further questioning of athletes reporting specific diet adherence in order to enhance nutritional knowledge and help treat and prevent eating disorders or disordered eating.

Efficacy of Popular Diets Applied by Endurance Athletes on Sports Performance: Beneficial or Detrimental? A Narrative Review

Endurance athletes need a regular and well-detailed nutrition program in order to fill their energy stores before training/racing, to provide nutritional support that will allow them to endure the harsh conditions during training/race, and to provide effective recovery after training/racing. Since exercise-related gastrointestinal symptoms can significantly affect performance, they also need to develop strategies to address these issues. All these factors force endurance athletes to constantly seek a better nutritional strategy. Therefore, several new dietary approaches have gained interest among endurance athletes in recent decades. This review provides a current perspective to five popular diet approaches: (a) vegetarian diets, (b) high-fat diets, (c) intermittent fasting diets, (d) gluten-free diet, and (e) low fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) diets. We reviewed scientific studies published from 1983 to January 2021 investigating the impact of these popular diets on the endurance performance and health aspects of endurance athletes. We also discuss all the beneficial and harmful aspects of these diets, and offer key suggestions for endurance athletes to consider when following these diets.

Exit Gluten-Free and Enter Low FODMAPs: A Novel Dietary Strategy to Reduce Gastrointestinal Symptoms in Athletes

Exercise-associated physiological disturbances alter gastrointestinal function and integrity. These alterations may increase susceptibility to dietary triggers, namely gluten and a family of short-chain carbohydrates known as FODMAPs (fermentable oligo-, di-, monosaccharides and polyols). A recent surge in the popularity of gluten-free diets (GFDs) among athletes without celiac disease has been exacerbated by unsubstantiated commercial health claims and high-profile athletes citing this diet to be the secret to their success. Up to 41% of athletes at least partially adhere to a GFD diet, with the belief that gluten avoidance improves exercise performance and parameters influencing performance, particularly gastrointestinal symptoms (GIS). In contrast to these beliefs, seminal work investigating the effects of a GFD in athletes without celiac disease has demonstrated no beneficial effect of a GFD versus a gluten-containing diet on performance, gastrointestinal health, inflammation, or perceptual wellbeing. Interestingly, the subsequent reduction in FODMAPs concurrent with the elimination of gluten-containing grains may actually be the factors affecting GIS improvement, not gluten. Pre-existent in the gastrointestinal tract or ingested during exercise, the osmotic and gas-producing effects of variably absorbed FODMAPs may trigger or increase the magnitude of exercise-associated GIS. Research using FODMAP reduction to address gastrointestinal issues in clinically healthy athletes is emerging as a promising strategy to reduce exercise-associated GIS. Applied research and practitioners merging clinical and sports nutrition methods will be essential for the effective use of a low FODMAP approach to tackle the multifactorial nature of gastrointestinal disturbances in athletes.

Assessment of Body Composition and Nutritional Risks in Young Ballet Dancers - The Bioelectrical Impedance Analysis

BACKGROUND

Young ballet dancers are at risk of health issues associated with altered nutritional status and of relative energy deficiency in sport compared to the general population.

AIM

To evaluate the nutritional status and body composition in ballet dancers.

MATERIALS AND METHODS

The study group consisted of 40 young ballet dancers (mean age 19.97 years). Height and weight were measured and body mass index was calculated in all subjects (mean BMI value 19.79 kg/m², SD: 2.051). Body composition was estimated using the bioelectrical impedance method.

RESULTS

The dancers' fat-free mass was 47.33 kg (SD: 5.064) and, on the average, body fat represented the 15.92% (SD: 16.91) of their body weight.

CONCLUSIONS

Ballet dancers, who usually show significantly lower BMI values compared to the general population, also displayed body fat values under the suggested range. Some screening for altered nutritional status should be performed. In addition, education programs should be recommended in young ballet dancers, in order to inform about energy and nutrition requirements for health and training and to prevent malnutrition-related problems.

Validation of the Athlete's Plate Nutrition Educational Tool: Phase I

Nutrition education visual tools are designed to help the general population translate science into practice. The purpose of this study was to validate the Athlete's Plate (AP) to ensure that it meets the current sport nutrition recommendations for athletes. Twelve registered dietitians (RDs; 10 female and 2 male) volunteered for the study. Each registered dietitian was asked to create three real and virtual plates at three different times corresponding to breakfast, lunch, and dinner, and the three different AP training loads, easy (E), moderate (M), and hard (H), divided into two weight categories (male 75 kg and female 60 kg). Data of the real and virtual plates were evaluated using Computrition software (v. 18.1; Computrition, Chatsworth, CA). Statistical analyses were conducted by SPSS (version 23.0; IBM, Armonk, NY) to compare the difference between each training load category (E, M, and H) and the recommendations. No statistically significant differences were found among the created plates and the recommendations for energy, carbohydrates, fat, and fiber for E, M, and H. Protein relative to body mass (BM) was higher than recommended for E (1.9 ± 0.3 g·kg-1 BM·day-1, p = .003), M (2.3 ± 0.3 g·kg-1 BM·day-1, p < .001), and H (2.9+0.5 g·kg-1 BM·day-1, p < .001). No differences were found for the macronutrient distribution by gender when correcting for kilograms of body mass. The authors conclude that the AP meets the nutrition recommendations for athletes at different training intensities for energy, carbohydrates, fat, and fiber, but exceeds the recommendations for protein. Further research should consider this protein discrepancy and develop an AP model that meets, besides health and performance goals, contemporary guidelines for sustainability.

Gluten and FODMAPS-Sense of a Restriction/When Is Restriction Necessary?

Gluten-free diet (GFD) is enjoying increasingly popularity, although gluten-free products are considerably more expensive. GFD is absolutely necessary for patients with celiac disease, as in this case even minor amounts of gluten can lead to the destruction of the intestinal mucosa. In addition, GFD is currently the best therapy to improve clinical symptoms of patients with non-celiac gluten sensitivity (NCGS), although the diet may not be as strict as that for patients with celiac disease. Beside gluten, other wheat components such as oligosaccharides and amylase trypsin inhibitors are discussed as triggers of NCGS in this review. An overlap between gastrointestinal symptoms in NCGS and irritable bowel syndrome (IBS) is described. Patients with NCGS attribute their symptoms to the consumption of gluten, while patients with IBS rarely describe gluten as a trigger. Recently, several studies have demonstrated that the introduction of a low FODMAP (fermentable oligo-, di-, monosaccharides, and polyols) diet reduced gastrointestinal symptoms in patients with IBS and this diet is suggested as the first choice of therapy in IBS. However, a low FODMAP diet also eliminates prebiotica and may negatively influence the gut microbiota. For this reason, the diet should be liberalized after symptom improvement. There is no evidence that a GFD is healthier than the standard diet. In contrast, GFD often is accompanied by nutritional deficiencies, mainly minerals and vitamins. Therefore, GFD and low FODMAP diets are not recommended for healthy subjects. Since wheat contains fructans belonging to FODMAPs), a GFD is not only gluten-free but also has less FODMAPs. Thus, symptom improvement cannot be correctly correlated with the reduction of either one or the other.

Dietary Practices Adopted by Track-and-Field Athletes: Gluten-Free, Low FODMAP, Vegetarian, and Fasting

Some track-and-field athletes implement special diets aiming to improve health and/or performance. An evidence-based approach to any diet is recommended to minimize the risks associated with unnecessary dietary restriction, which may potentially do more harm than good. Four prevalent diets are reviewed in this study: (a) gluten-free; (b) low fermentable oligosaccharides, disaccharides, monosaccharides, and polyols (FODMAP); (c) vegetarian; and (d) fasting diets. Recently, gluten-free diets and low FODMAP diets have emerged as novel regimes thought to improve gastrointestinal health and reduce the risk of exercise-associated gastrointestinal symptoms. No direct beneficial outcomes have been associated with avoiding gluten for clinically healthy athletes. Indirectly, a gluten-free diet is associated with other dietary changes, particularly FODMAP reduction, which may improve adverse gastrointestinal symptoms. Vegetarian diets can optimally support athletic demands. However, attention is required to ensure adequate energy and intake of specific nutrients that are less abundant or less well absorbed from plant sources. Finally, fasting is a long-standing concept that is undertaken on a voluntary and obligatory basis. Despite limited supporting research, voluntary fasting is a popular alternative to conventional diets perceptually offering health and body composition benefits. Strict obligatory fasting guidelines likely require the implementation of tailored nutrition strategies to help athletes cope with athletic demands. Overall, a multitude of factors influence adherence to special diets. Even when adherence to a special diet is a necessity, education and advice from an accredited dietitian/nutritionist are recommended for track-and-field athletes to optimize nutrition for health and performance.

Changes in Sport Nutrition Knowledge, Attitudes/Beliefs and Behaviors Following a Two-Year Sport Nutrition Education and Life-Skills Intervention among High School Soccer Players

The purpose of this study was to examine the impact of a sport nutrition education and life-skills intervention on sport nutrition knowledge (SNK), attitudes/beliefs and dietary behaviors relevant to sport nutrition among high school (HS) soccer players. Three assessments were done over the 2-year intervention (baseline = time 1, end year 1 = time 2, end year 2 = time 3). Participants (n = 217; females = 64%; Latino = 47.5%; 14.9 ± 0.9-year; 46.5% National School Breakfast/Lunch Program) were assigned to an intervention group (IG, n = 153; 9 schools) or comparison group (CG, n = 64; 4 schools) based on geographical location. Differences over time were examined based on group, sex, socioeconomic status (SES) and race/ethnicity. The IG increased SNK scores by ~10% (time 1 = 51.6%; time 3 = 60.9%; p ≤ 0.001), with the greatest change in the female IG vs. CG and no differences in male IG vs. CG. Daily breakfast consumption was 53.7% in both groups. IG players were 3 times more likely (95%CI = 2.59, 7.77) to report trying to eat for performance (IG = 48.7% vs. CG = 30.2%). By time 3, IG players were less likely to report that 'diet met nutritional requirements' (31.6%) compared to CG (47.6%). For IG, the consumption of lunch (≥5-days/week) did not change (92.2⁻93.4%), but declined in the CG (90.6%) (p = 0.04). No other differences by sub-population (race/ethnicity, SES) were observed. Our findings indicate that HS athletes are motivated to learn and improve diet behaviors, and benefit from team-based nutrition interventions. Future interventions should consider delivery of curriculum/experiential learning during a defined training period, with messages reinforced with supports at home, school and athletic settings.