Nutrition Knowledge of Collegiate Athletes in the United States and the Impact of Sports Dietitians on Related Outcomes: A Narrative Review

In the last decade, the number of full-time registered dietitians (RDs) serving intercollegiate athletes in the United States has more than quadrupled. However, many student athletes may be at increased risk of nutrition-related problems that impact physical and academic performance, which include inadequate macronutrients, inadequate micronutrients, and excessive macronutrients. This narrative review reports the current literature to date on nutrition-related knowledge in collegiate athletes and the impact of sports RDs on student athletes’ nutrition knowledge and behaviors. To date, only observational and quasi-experimental studies have been published with regard to changes in nutrition knowledge and behaviors in NCAA athletes. While these studies report benefits of the RD as a member of the interdisciplinary student athlete support team, more well-designed randomized control trials are warranted to determine benefits related to health outcomes and sport-specific performance outcomes.     

Sports Nutrition and Food Knowledge among Malaysian University Athletes

Sports nutrition and food knowledge can influence athletes’ dietary intake, potentially affecting athletic performance. Limited studies have been conducted to identify sports nutrition and food knowledge among Malaysian university athletes. This study aimed to determine Malaysian university athletes’ knowledge of sports nutrition and food, and their reference sources and preferred sports nutrition education programme. Seventy athletes (52.9% females, mean weight = 61.8 kg; height = 1.66 m) aged 18.5–22.4 years responded to an online survey administered using a Google Form. A score of ≥60% was considered as adequate knowledge. The average overall knowledge score was 58.6%. The highest knowledge score was for sports nutrition, specifically food intake periodicity (84.8%), while the lowest was for general food knowledge on fat (44.6%). An analysis of specific questions revealed a lack of understanding about the recommended daily intake of fruits and vegetables (only 14.3% answered correctly), the roles of vitamins and minerals in energy production (21.4%), and good sources of unsaturated fat (37.2%). The academician was the primary reference source (81%), while magazines were the least referred to sources (36%). The university athletes preferred sports camps (33%) over the other nutrition education programme options. More initiatives are needed to improve Malaysian university athletes’ understanding and knowledge of sports nutrition and general food.     

Energy and Macronutrients Intake in Indoor Sport Team Athletes: Systematic Review

Indoor team sports are characterized by matches that are shorter in duration and with frequent substitution (high-intensity intermittent). The main goal of teams is to best cover athletes’ physiological demands, while meeting their dietary intake needs is critical. The aim of this study is to conduct a systematic review of the dietary intake of indoor team sports athletes and to analyze whether they comply with nutritional recommendations. A search of PubMed-MEDLINE, Web of Science, and Scopus databases from 2008 to July 2022 was conducted and 2727 documents were identified. The studies focused on adult professional or semi-professional volleyball, basketball, handball, or futsal athletes. Two independent researchers screened and extracted the data, with 20 documents included after they met the inclusion criteria. Most of the athletes, both men and women, did not meet the official recommendations based on under-consumption (energy and carbohydrates) or over-consumption (fats). In relation to protein, 28.6% of studies met the recommendations, with 50% of those who did not meet it being due to under-consumption. Although there are references on athletes’ dietary intakes, there are no references considering sexes or types of sport. More adapted recommendations are needed in order to more precisely evaluate athletes’ intake to know if they meet their real nutritional requirements.     

Position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and Athletic Performance

It is the position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine that physical activity, athletic performance, and recovery from exercise are enhanced by optimal nutrition. These organizations recommend appropriate selection of foods and fluids, timing of intake, and supplement choices for optimal health and exercise performance. This updated position paper couples a rigorous, systematic, evidence-based analysis of nutrition and performance-specific literature with current scientific data related to energy needs, assessment of body composition, strategies for weight change, nutrient and fluid needs, special nutrient needs during training and competition, the use of supplements and ergogenic aids, nutrition recommendations for vegetarian athletes, and the roles and responsibilities of sports dietitians. Energy and macronutrient needs, especially carbohydrate and protein, must be met during times of high physical activity to maintain body weight, replenish glycogen stores, and provide adequate protein to build and repair tissue. Fat intake should be sufficient to provide the essential fatty acids and fat-soluble vitamins, as well as contribute energy for weight maintenance. Although exercise performance can be affected by body weight and composition, these physical measures should not be a criterion for sports performance and daily weigh-ins are discouraged. Adequate food and fluid should be consumed before, during, and after exercise to help maintain blood glucose concentration during exercise, maximize exercise performance, and improve recovery time. Athletes should be well hydrated before exercise and drink enough fluid during and after exercise to balance fluid losses. Sports beverages containing carbohydrates and electrolytes may be consumed before, during, and after exercise to help maintain blood glucose concentration, provide fuel for muscles, and decrease risk of dehydration and hyponatremia. Vitamin and mineral supplements are not needed if adequate energy to maintain body weight is consumed from a variety of foods. However, athletes who restrict energy intake, use severe weight-loss practices, eliminate one or more food groups from their diet, or consume unbalanced diets with low micronutrient density, may require supplements. Because regulations specific to nutritional ergogenic aids are poorly enforced, they should be used with caution, and only after careful product evaluation for safety, efficacy, potency, and legality. A qualified sports dietitian and in particular in the United States, a Board Certified Specialist in Sports Dietetics, should provide individualized nutrition direction and advice subsequent to a comprehensive nutrition assessment.     

Integrating sustainable nutrition into health-related institutions: a systematic review of the literature

ObjectivesSustainable nutrition is increasingly important, as the food system contributes one third of greenhouse gas emissions. Sustainable nutrition, or sustainable diet, refers to diets with low environmental impacts that contribute to food security and health. This systematic review aimed to identify factors that influence whether professionals in health-related institutions integrate sustainable nutrition into their practice.MethodsA mixed-methods systematic review was conducted using the MEDLINE, Embase, PsycINFO, and CINAHL databases. To be included, the studies had to document perspectives on sustainable nutrition from health professionals, including dietitians, students and educators in health sciences, public health officers, and hospital food service managers. Data extraction focused on perceived barriers, facilitating factors, and top recommendations for promoting sustainable nutrition.SynthesisTwenty studies were included, most of which focused on dietitians. Data analysis revealed that 25 factors influenced the integration of sustainable nutrition into professional practice. The factors most reported in the included studies were perceived knowledge of sustainable nutrition, self-efficacy, awareness of environmental issues, and perceiving the promotion of sustainable nutrition to be part of one’s professional role. Increasing societal support through awareness campaigns and increasing institutional support through guidelines, information tools, and financial support were also frequently mentioned.ConclusionSustainable nutrition is a multifaceted concept; integrating it into already complex professional practices is therefore challenging. At the present time, dietitians seem to be the health professionals predominantly researched regarding their views on sustainable nutrition. Many concrete avenues to promote sustainable nutrition were identified through this review.Electronic supplementary materialThe online version of this article (10.17269/s41997-020-00394-3) contains supplementary material, which is available to authorized users.     

Case study: nutrition challenges of a marathon runner with a gastric bypass

A new type of athlete is appearing in the offices of sports dietitians: formerly obese people who have undergone gastric bypass surgery and now aspire to be marathoners, triathletes, and other types of endurance athletes. The standard nutrition advice offered to bypass patients is contrary to the standard sports advice given to athletes. Bypass athletes need to limit carbohydrates, fluids, and energy intake and consume a protein-based diet. This case study describes the sport nutrition concerns of a woman who, after having gastric bypass surgery, trained to run a marathon (42 km). Because of her limited ability to consume food and fluids, she experienced difficulty preventing fatigue and dehydration during her long training runs and the marathon itself. She learned through trial and error how to survive the nutritional challenges and complete the marathon. Health professionals need to be aware of the potential medical risks associated with endurance exercise in gastric bypass patients. Research is needed to determine the best sports nutrition practices for bypass patients. Only then can sport dietitians better educate this small but growing contingent of endurance athletes so the athletes can meet their training and performance goals and reduce their risk of experiencing serious health consequences.     

Psychosocial factors and eating behaviors according to the stages of change in nutrition management among elementary and middle school athletes

BACKGROUND/OBJECTIVESThis study examined the differences in psychosocial factors and eating behaviors by the stages of change (SOC) in nutrition management among elementary and middle school athletes.SUBJECTS/METHODSSubjects were young athletes recruited from the athletic clubs of 10 organizations. Subjects responded to a survey questionnaire, and data on 167 athletes were analyzed. Subjects were grouped into the pre-action or action stage in nutrition management. The χ² test, t-test, analysis of covariance, and correlation analysis were used in data analysis.RESULTSAthletes in the action stage (62.3%) compared to the pre-action stage, showed a higher self-efficacy (P < 0.01), and felt more confidence in performing specific eating behaviors (P < 0.05 to P < 0.01). Those in the action stage had more favorable beliefs regarding nutrition (P < 0.001) and agreed less strongly on the specific misconceptions/disadvantages of nutrition (P < 0.01) than those in the pre-action stage. Eating behaviors (P < 0.001) and subscales of the eating behaviors (P < 0.05 to P < 0.01) also differed significantly by the SOC group. Place of eating dinner (P < 0.05) and the person who prepares dinner (P < 0.05) showed significant differences by the SOC group. The relationship of self-efficacy, beliefs regarding nutrition, and eating behaviors to the SOC differed by sports type. Beliefs for football athletes, self-efficacy, and beliefs for baseball athletes were correlated significantly with the SOC, whereas all 3 variables were related to the SOC for handball and other athletes.CONCLUSIONSThis study showed differences in psychosocial factors and eating behaviors between the pre-action and action stages. Nutrition education should include strategies to help young athletes modify their beliefs, mainly misconceptions/disadvantages of nutrition, increase self-efficacy, and adopt specific and desirable eating behaviors. Nutrition education might employ different strategies considering the sports type that student-athletes participate.     

Research and application of current topics in sports nutrition

The increased focus on fitness and subsequent research in the exercise field has expanded the role of nutrition as it relates to sports medicine. A literature review and application are presented for the anatomical, physiological, and biochemical mechanisms of caffeine in endurance events; iron status and physical performance; regulation of fluid and electrolyte balance during exercise; and stress fractures, calcium, and diet. The goal is to provide dietitians with information that is needed to formulate and rationalize recommendations regarding sports nutrition. An expanded role is offered to dietitians who wish to communicate sports medicine information to other health professionals and to consumers who engage in exercise. Nutrition and sports medicine information could benefit consumers and other health professionals in employee wellness programs in medical centers and organizations, fitness centers, sports medicine clinics, schools, and athletic teams.     

Functional foods and food supplements for athletes: from myths to benefit claims substantiation through the study of selected biomarkers

The development of the sports food market and industrial involvement have led to numerous nutritional studies to define the type of nutrients that are most suited to support energy metabolism, fluid balance and muscle function. The key question in many of these studies was: 'Does the product lead to a significant product/consumer benefit that can be used as a claim on the package?' New methods and techniques have been developed, partly with sponsorship of the food industry, with the goal of measuring the effects of specific nutrients and supplements on athletic performance and metabolism. In line with this development, a wide variety of supplements and sports foods/drinks labelled with various performance or health benefit statements have been launched on the sports nutrition market. Although a variety of products have been tested clinically, there are also many products on the market with benefit claims that cannot be supported by sound nutritional and sports physiological science. The current short review highlights some of the methods and biomarkers that are used to substantiate product/consumer benefit claims for foods and drinks that are marketed as functional foods for athletes.     

Consumers’ Exposure to Nutrition and Health Claims on Pre-Packed Foods: Use of Sales Weighting for Assessing the Food Supply in Slovenia

Insights into the use of health-related information on foods are important for planning studies about the effects of such information on the consumer’s understanding, purchasing, and consumption of foods, and also support further food policy decisions. We tested the use of sales data for weighting consumers’ exposure to health-related labeling information in the Slovenian food supply. Food labeling data were collected from 6342 pre-packed foods available in four different food stores in Slovenia. Consumers’ exposure was calculated as the percentage of available food products with particular food information in the food category. In addition, 12-month sales data were used to calculate sales weighted exposure as a percentage of sold food products with certain food information in the food category. The consumer’s in-store and sales-weighted exposure to nutrition claims was 37% and 45%, respectively. Exposure to health claims was much lower (13%, 11% when sales-weighted). Health claims were mainly found in the form of general non-specific claims or function claims, while children’s development and reduction of disease risk claims were present on only 0.1% and 0.2% of the investigated foods, respectively. Sales data were found very useful for establishing a reliable estimation of consumers’ exposure to information provided on food labels. The high penetration of health-related information on food labels indicates that careful regulation of this area is appropriate. Further studies should focus on assessing the nutritional quality of foods labeled with nutrition and health claims, and understanding the importance of such labeling techniques for consumers’ food preferences and choices.     

Performance Food: Promoting foods with a functional benefit in sports performance

The food choices and eating habits of athletes and sportspeople are influenced by their lifestyle, the practical considerations of their sports and the physiological demands of training and competition programmes. There is a growing interest in foods with a functional benefit in sports performance and in products and foods which can enhance recovery post‐exercise and therefore support a faster return to training. This paper provides an overview of the nutritional functions of foods and fluids of current scientific interest to athletes and sportspeople. Practical dietary strategies are provided to illustrate how emerging research can be translated into food ideas, which can enhance the functional benefits to their maximum potential within existing scientific recommendations to minimise reliance on unnecessary dietary supplements.     

Perceptions of Nut Consumption amongst Australian Nutrition and Health Professionals: An Online Survey

Habitual nut consumption is associated with reduced risk of chronic diseases; however, consumption levels in Australia are below recommendations. This study examined perceptions and knowledge regarding nut consumption among Australian healthcare professionals and their provision of nut consumption recommendations. A cross-sectional online survey of Australian health professionals was conducted in February–April 2020. Questions in the survey included demographic details, participants’ perceptions of nut consumption, and nut consumption recommendations they may make to clients and patients. A total of 204 health professionals completed the survey, of which 84% were dietitians or nutritionists. Health professionals demonstrated basic nutritional knowledge regarding nut consumption; however, non-dietitians/nutritionists lacked knowledge of long-term benefits of nut consumption. Dietitians/nutritionists were more likely to agree that nuts are healthy and do not cause weight gain when compared to non-dietitians/nutritionists (p = 0.021). A total of 63% of health professionals advised at least some of their clients to eat more nuts, and this was higher among dietitians/nutritionists (68%) than non-dietitians/nutritionists (31%). While basic nutritional knowledge regarding nut consumption was observed among all health professionals, there is scope for further education, particularly for non-dietitians/nutritionists, to ensure that nutrition information provided to patients and clients is accurate and reflects the current evidence base.     

Diet Quality of Elite Australian Athletes Evaluated Using the Athlete Diet Index

While athletes’ nutrient intakes have been widely reported, few studies have assessed the diet quality of athletes. This is the first study to evaluate the diet quality of athletes using the purpose-built Athlete Diet Index (ADI). A convenience sample of 165 elite athletes from Australian sporting institutions completed the ADI online, with subsequent automated results provided to their respective accredited sports dietitians (ASDs). At the completion of athlete participation, ASDs (n = 12) responded to a range of survey items using a Likert scale (i.e., 1 = strongly agree to 5 = strongly disagree) to determine the suitability of the ADI in practice. Differences in ADI scores for demographics and sport-specific variables were investigated using independent t-tests, analysis of variance (ANOVA) and Bonferroni multiple comparisons. Spearman’s rank correlation was used to assess the association between total scores and demographics. The mean total ADI score was 91.4 ± 12.2 (range 53–117, out of a possible 125). While there was no difference in total scores based on demographics or sport-specific variables; team sport athletes scored higher than individual sport athletes (92.7 vs. 88.5, p < 0.05). Athletes training fewer hours (i.e., 0–11 h/week) scored higher on Dietary Habits sub-scores compared with athletes training more hours (≥12 h/week; p < 0.05), suggesting that athletes who train longer may be at risk of a compromised dietary pattern or less than optimal nutrition practices that support training. Most (75%) ASDs surveyed strongly agreed with the perceived utility of the ADI for screening athletes and identifying areas for nutrition support, confirming its suitability for use in practice.     

A Comparison of Dietary Habits between Recreational Runners and a Randomly Selected Adult Population in Slovenia

Introduction

The aim of the study was to compare the dietary habits of recreational runners with those of a random sample of the general population. We also wanted to determine the influence of gender, age and sports performance of recreational runners on their basic diet and compliance with recommendations in sports nutrition.

Methods

The study population consisted of 1,212 adult Slovenian recreational runners and 774 randomly selected residents of Slovenia between the ages of 18 and 65 years. The data on the dietary habits of our subjects was gathered by means of two questionnaires. The following parameters were evaluated: the type of diet, a food pattern, and the frequency of consumption of individual food groups, the use of dietary supplements, fluid intake, and alcohol consumption.

Results

Recreational runners had better compliance with recommendations for healthy nutrition than the general population. This pattern increased with the runner’s age and performance level. Compared to male runners, female runners ate more regularly and had a more frequent consumption of food groups associated with a healthy diet (fruit, vegetables, whole grain foods, and low-fat dairy products). The consumption of simple sugars and use of nutritional supplements by well-trained runners was inadequate with values recommended for physically active individuals.

Conclusion

Recreational runners are an exemplary population group that actively seeks to adopt a healthier lifestyle.     

Position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine: Nutrition and athletic performance

It is the position of the American Dietetic Association, Dietitians of Canada, and the American College of Sports Medicine that physical activity, athletic performance, and recovery from exercise are enhanced by optimal nutrition. These organizations recommend appropriate selection of food and fluids, timing of intake, and supplement choices for optimal health and exercise performance. This position paper reviews the current scientific data related to the energy needs of athletes, assessment of body composition, strategies for weight change, the nutrient and fluid needs of athletes, special nutrient needs during training, the use of supplements and nutritional ergogenic aids, and the nutrition recommendations for vegetarian athletes. During times of high physical activity, energy and macronutrient needs—especially carbohydrate and protein intake—must be met in order to maintain body weight, replenish glycogen stores, and provide adequate protein for building and repair of tissue. Fat intake should be adequate to provide the essential fatty acids and fat-soluble vitamins, as well as to help provide adequate energy for weight maintenance. Overall, diets should provide moderate amounts of energy from fat (20% to 25% of energy); however, there appears to be no health or performance benefit to consuming a diet containing less than 15% of energy from fat. Body weight and composition can affect exercise performance, but should not be used as the sole criterion for sports performance; daily weigh-ins are discouraged. Consuming adequate food and fluid before, during, and after exercise can help maintain blood glucose during exercise, maximize exercise performance, and improve recovery time. Athletes should be well-hydrated before beginning to exercise; athletes should also drink enough fluid during and after exercise to balance fluid losses. Consumption of sport drinks containing carbohydrates and electrolytes during exercise will provide fuel for the muscles, help maintain blood glucose and the thirst mechanism, and decrease the risk of dehydration or hyponatremia. Athletes will not need vitamin and mineral supplements if adequate energy to maintain body weight is consumed from a variety of foods. However, supplements may be required by athletes who restrict energy intake, use severe weight-loss practices, eliminate one or more food groups from their diet, or consume high-carbohydrate diets with low micronutrient density. Nutritional ergogenic aids should be used with caution, and only after careful evaluation of the product for safety, efficacy, potency, and whether or not it is a banned or illegal substance. Nutrition advice, by a qualified nutrition expert, should only be provided after carefully reviewing the athlete's health, diet, supplement and drug use, and energy requirements. J Am Diet Assoc. 2000;100:1543-1556.     

Athletes’ and Coaches’ Perceptions of Nutritional Advice: Eating More Food for Health and Performance

Background: Low energy availability results in physiological adaptations which contribute to unfavourable health outcomes. Little information exists on perceptions of nutritional advice to eat more food to maintain health and enhance performance. The aim of this study was to explore athletes’ and coaches’ perceptions towards advice to athletes to eat larger than their current quantities of food and to explore how nutritionists could deliver this advice. Methods: Semi-structured interviews (~20 min in length) were conducted using online communication technology, audio-recorded, and transcribed verbatim. The interview explored perceptions of the nutritional advice provided, its role in health and performance, and the challenges to eating larger amounts of food. Data were analysed using NVIVO 1.2 using an inductive thematic approach. Results: Nine elite athletes (female = 6; males = 3) and nine high-performance coaches (female = 3; male = 6) completed the semi-structured interviews. Athletes reported improved training consistency, fewer injuries and illnesses, and improved resilience when consuming adequate energy and nutrients to meet their needs. Lack of time and meal preparation difficulties were the main challenges faced to fuelling. Conclusions: Although education about under-fuelling is important, motivating, enabling, and supporting athletes to change behaviour is pivotal to increasing athlete self-awareness and to make long-term nutritional changes.     

Position of the American Dietetic Association: food fortification and dietary supplements

Wise food choices provide the necessary foundation for optimal nutrition. Science has not fully identified the specific chemical components that account for the benefits of healthy eating patterns. Selection of a variety of foods, using tools such as the USDA/HHS Dietary Guidelines for Americans and the USD A Food Guide Pyramid, is the best way to provide a desirable balance, without excessive intakes of macronutrients, micronutrients and other beneficial components of foods. Nevertheless, for certain nutrients and some individuals, fortification, supplementation, or both may also be desirable. Nutrient intakes from all these sources should be considered in dietary assessments, planning and recommendations. The recommendations of the National Academy of Sciences' Food and Nutrition Board provide a sound scientific basis for vitamin and mineral intakes. Intakes exceeding those recommendations have no demonstrated benefit for the normal, healthy population. Dietetics professionals should base recommendations for use of fortified foods or supplements on individualized assessment and sound scientific evidence of efficacy and safety. It is the position of the American Dietetic Association that the best nutritional strategy for promoting optimal health and reducing the risk of chronic disease is to wisely choose a wide variety of foods. Additional vitamins and minerals from fortified foods and/or supplements can help some people meet their nutritional needs as specified by science-based nutrition standards such as the Dietary Reference Intakes (DRI) J Am Diet Assoc. 2001; 101:115–125     

Dietitians' perceptions about and personal nutrition practices for cancer risk reduction

This study was undertaken to examine the beliefs and practices of dietitians in relation to cancer risk reduction through nutrition. Respondents to the national survey (N=384, 70 percent) were similar in demographic, educational, and professional characteristics to the American Dietetic Association census data. They reported a strong preventive health orientation: mean performance on 10 preventive health behaviors was 77.5 on a 100 point scale. Half (53 percent) believed cancer would be serious if they developed it, 47 percent believed it was not likely that they would. About 20 percent of the respondents felt that the role of nutrition in cancer etiology was unclear. Dietitians believed strong research support existed for increasing whole grains, fruits and vegetables, and fiber to reduce cancer risk but that little evidence supported use of dietary supplements. Dietitians regularly practiced 75 percent of nutrition recommendations they believed to be effective in reducing cancer risk. Beliefs about the effectiveness of a recommendation accounted for the largest percentage of variance on nutritional practices. While dietitians reported many preventive health practices, including following nutrition recommendations, they seemed to be doing so for reasons other than preventing cancer.Nancie S. Merlino is Assistant Professor, Nutrition and Food Science, Wayne State University, Detroit, MI 48202 and James H. Price, Professor of Health Promotion, Department of Health Promotion, University of Toledo, Toledo, OH 43606.Acknowledgement goes to Stephen Jurs, PhD; Fredrick Andres, PhD; and John Kish, PhD for assistance in design and analysis.