Influence of performance level on dietary supplementation in elite Canadian athletes

Differences in Consumption Behaviour of Dietary Supplements in Competitive Athletes Depends on Sports Discipline

BACKGROUND

The consumption of dietary supplements (DS) is widespread among the general population and competitive athletes. However, only a few competitive athletes seek information from experts about the effects and use of DS. Furthermore, it is currently unknown whether certain sports have a higher affinity for DS than others.

METHODS

This study aimed to identify differences between different sports categories and subgroups that may have a very high affinity for DS. For this purpose, competitive athletes were surveyed. The survey included the type of sport, the training frequency, the number of competitions, the consumption behaviour of five DS categories (general health, regeneration promotion, performance enhancement, booster, and weight loss) as well as personal data such as biological sex and age. Subsequently, correlations, configural frequencies (CFA), and multiple correspondence analyses (MCA) were used to identify subgroups with a high affinity of consumption behaviour.

RESULTS

A total of 409 questionnaires could be evaluated. It was found that all DS categories except weight loss were related. In addition, it was observed that in sports from the power category and from the endurance category, there was even higher consumption behaviour than in other sports categories. Male power athletes in particular have a higher affinity for consuming DS than other subgroups.

CONCLUSIONS

This study shows that there is a clear different consumption behaviour depending on the type of sport. Male power athletes in particular are the subgroup with the greatest consumption behaviour and therefore require special education on the effects and use of DS. This subgroup in particular should receive increased attention in counselling on DS to minimise the possible risks of DS use.

A Behaviourally Informed Approach to Reducing the Risk of Inadvertent Anti-doping Rule Violations from Supplement Use

For many reasons, athletes' use of supplements is highly prevalent across sports and competitive levels, despite the risk of these products containing a substance on the World Anti-Doping Agency Prohibited List. Contravening anti-doping rules through supplement use could have serious consequences for competitive athletes (e.g., ineligibility from major competitions, loss of medals and funding) due to the principle of strict liability. Indiscriminate supplement use also poses a risk to athlete health. To reduce the possibility of ingesting a supplement containing prohibited substances, independent quality assurance and certification programs have been established (e.g., Informed Sport). However, these programs do not completely eliminate risk, leading to some anti-doping organisations promoting a 'just say no' to supplements stance. Yet, this approach can be problematic as a small number of supplements may be necessary for athletes to consume, in certain situations. Recognising that athletes will continue to use these heavily marketed products, this narrative review describes a theoretically underpinned and systematic approach to preventing inadvertent doping by considering the barriers to and enablers of athlete adherence to risk minimisation supplement use guidelines (RMSUG). By outlining a conceptual shift towards a behaviourally informed approach, this review serves to stimulate the development of multifaceted interventions to prevent inadvertent doping through supplement use. Recognising that risk-minimised supplement use involves a myriad of behaviours, the problem of inadvertent doping through supplement use is framed, and research appraised, through the lens of the Behaviour Change Wheel.

Assessment of dietary nitrate supplementation: prevalence of use, knowledge, attitudes and beliefs among active Australians

Introduction

Use of nitrate as a dietary supplement has gained popularity among athletes and recreationally active individuals to enhance exercise performance. However, the prevalence and patterns of use, and knowledge of nitrate as a dietary supplement are unknown.

Methods

Individuals (≥16y) completed a 42-item online questionnaire to collect (i) sociodemographic information; (ii) participation in activity and sport; (iii) nitrate supplementation use and reasons; (iv) attitudes and beliefs regarding information sources and the safety of nitrate as a dietary supplement; and (v) knowledge of dietary nitrate supplements.

Results

In total, 1,404 active adults (66% female) took part in the study. Only about one in 10 respondents (11.9%) reported they had consumed dietary nitrate ("users") in the past, most commonly as beetroot juice (31.3%). Over two-thirds (69.4%) of users could not correctly identify the correct timing of intake relative to performance time to best improve exercise performance, and most users (82.3%) were unsure of the contraindications to oral consumption of dietary nitrate supplements. Only 3.9% of users experienced adverse effects after ingesting dietary nitrate supplements. Among non-users, the most common reasons respondents selected for not using dietary nitrate supplements were "I do not think I need to" (70.2%) and "I have never thought about it" (69.2%).

Discussion

There is evidence to support the efficacy of dietary nitrate intake in improving exercise performance. However, findings from this study suggest dietary nitrate is under-utilized. Educational messages that target dietary nitrate consumption should be targeted toward nutritionists, coaches, and exercise physiologists to bridge the gap between knowledge-to-practice.

Energy Expenditure, Dietary Energy Intake, and Nutritional Supplements in Adolescent Volleyball Athletes versus Nonathletic Controls

Evidence suggests that athletes competing in team sports do not follow dietary recommendations. However, only few studies have investigated energy needs and supplement use in adolescent athletes, and whether they are meeting their energy requirements. This observational study examined energy expenditure, dietary energy intake, and use of nutritional supplements in 58 adolescent (14-17 years old) volleyball athletes (15 males, 43 females) and 58 age-matched nonathletic controls (13 males, 45 females). Participants completed an online survey including questions on demographic information, body mass, and a series of standardized questionnaires assessing energy expenditure, dietary energy, macronutrient, micronutrient, and supplement intake. Energy expenditure relative to body mass was higher in athletes than nonathletes by 13 kcal/kg/day (group effect, p < 0.001), and in males compared to females by 5.7 kcal/kg/day (sex effect, p = 0.004). Athletes had higher energy intake than nonathletes (+6.4 kcal/kg/day, p = 0.019) and greater consumption of fruits (p = 0.034), vegetables (p = 0.047), grains (p = 0.016), dairy (p = 0.038), meats and meat alternatives (p < 0.001), as well as higher intakes of fat (p < 0.001), carbohydrates, protein, sugar, fiber, vitamin C, calcium, and sodium (p = 0.05) compared to nonathletes. The average protein intakes exceeded the upper recommendations in all groups, suggesting that this is not a nutrient of concern for young volleyball athletes. However, athletes were only meeting 60% of the estimated energy requirements (EER) for their age, height, body mass, and physical activity score, (3322 ± 520 kcal/day), while nonathletes were meeting 74% of the EER (p < 0.001). The relative energy balance of male athletes was lower compared to both female athletes (p = 0.006) and male nonathletes (p = 0.004). Finally, more athletes reported using performance-related supplements than nonathletes, but there were no differences in the consumption of other dietary supplements. Overall, when compared to nonathletic controls, both male and female adolescent volleyball athletes were found to match their higher energy expenditure with a greater dietary energy intake; however, all adolescents were below the estimated energy requirements, a finding more profound among the volleyball athletes.

Prevalence and Attitudes Towards Using Protein Supplements Among Female Gym Users: An Online Survey

Background:

Protein supplements have become a widespread practice amongst athletes and gym users worldwide. However, studies on the use of protein supplements among female gym users in Saudi Arabia are lacking.

Objective:

The aim of this study was to investigate the prevalence of protein supplement usage among female gym users and their attitudes towards protein supplementation in Riyadh city, Saudi Arabia.

Methods:

In this cross-sectional study, 502 female gym users aged ≥18 years completed a structured, self-administered online questionnaire on the usage of protein supplementation. Socio- demographic information, anthropometry, health status, exercise frequency, attitudes and knowledge regarding protein supplements were obtained.

Results:

The overall prevalence rate of protein supplement use among the study respondents was 36.3%. There were significant associations between the use of protein supplements and educational level (p< 0.05), the duration of being a gym member (p< 0.05) and frequency of gym visits per week (p< 0.05). Whey protein was the predominantly used supplement (57.8%), and the reason attributed to the use of protein supplement was muscle building (53.9%). The main sources of information regarding protein supplement use included the internet (30.2%) followed by gym coaches (25.3%).

Conclusion:

Our findings demonstrated that a considerable number of females exercising in gyms use protein supplements, and most rely on unreliable sources for decision-making of protein supplements use. Nutritional education and consultations regarding protein supplement use are warranted.

Education Interventions to Improve Knowledge, Beliefs, Intentions and Practices with Respect to Dietary Supplements and Doping Substances: A Narrative Review

The misuse of dietary supplements and doping substances is commonly associated with toxicity, nutritional imbalances, and health and psychological consequences. This is alarming especially in light of the increasing prevalence of the use of dietary supplements and doping, particularly among young adults including athletes. There is evidence that education interventions can lead to improved knowledge, intentions, and practices. However, no review has summarized and evaluated the effectiveness of such interventions. The aim of this article is to review the characteristics, contents and effects of education interventions that were designed and implemented to improve knowledge, attitudes, beliefs and intentions with respect to the use of dietary supplements and doping agents in different populations. PubMed, Scopus, CINAHL, PsycInfo and Google Scholar were searched for English-language education interventions targeting dietary supplements and doping substances. A total of 20 articles were identified and have generally provided consistent findings. Most interventions reported a significant improvement in knowledge on dietary supplements and doping agents. Unfortunately, the heavy reliance on self-reported assessment tools limits the validity of these interventions, with almost all articles targeting athletes and adolescents.

Knowledge and Prevalence of Supplements Used by Brazilian Resistance Training Practitioners Before Coronavirus Outbreak

INTRODUCTION

The use of dietary supplements and ergogenic aids (DSEA) is popular among physical activity enthusiasts. Particularly, resistance training (RT) practitioners represent important DSEA consumers due to its easy access and the appeal of claims related to muscle hypertrophy, aesthetics, and physical performance improvements.

METHODS

Our aim was to study knowledge, prevalence, and profile of DSEA used by Brazilian recreational RT practitioners. For this, RT practitioners of both sexes (n=129, female=58 and male=71) answered a paper-based questionnaire. The questionnaire was specifically created for the studied population to assess different aspects of the DSEA used and sociodemographic variables.

RESULTS

Seventy-seven percent of the participants (n=99) declared that they had already used DSEA. The majority (53%) searched the internet to obtain information about DSEA. Whey protein (66%) was the most used followed by branched chain amino acids (48%).

CONCLUSION

The use of DSEA, before coronavirus outbreak, was popular among RT practitioners; protein and amino acids were the most used DSEA. Most users used internet to obtain information about DSEA. The results suggest the need for appropriate attitude and guidance by health professionals who deal with this population, especially dietitians, nutritionists, and physical training professionals in order to promote best and security practices.

Dietary Supplementation Practices among Varsity Athletes at a Canadian University

BACKGROUND

Given the risks of inadvertent doping associated with dietary supplement (DS) use, it is critical to explore the extent of dependence of varsity athletes on DS to improve performance and support recovery. The purpose of this study was to gain insight into dietary supplementation practices among varsity athletes in a university setting in Ontario, Canada.

METHODS

An online DS use questionnaire was completed by 302 varsity athletes (30.5% male, 69.5% female; 20.5 ± 1.8-year old) who were competing in intermittent, power and endurance-based sports at the University of Guelph. The data from supplement users were analyzed using a Chi-square analysis to investigate type of DS consumption, frequency of use and reasons for use.

RESULTS

Overall, 58.3% of athletes reported having used at least one type of DS in the past six months. Gender and age had significant associations with prevalence of DS use, with male athletes and athletes over 20-year old being more likely to be DS users. The most frequently reported reasons for consuming DS were to maintain good health, increase energy, promote recovery, correct or prevent micronutrient deficiencies and supply convenient forms of energy and/or macronutrients. Although, most athletes were using reliable sources of information, health care professionals, 58.6% still mentioned wanting to become more knowledgeable about DS.

CONCLUSIONS

Findings from this study may guide the development of educational materials needed to address knowledge gaps on DS among varsity athletes.

The determination of common anabolic steroid and stimulants in nutritional supplements by HPLC-DAD and LC-MS

A high-performance liquid chromatography method employing a diode-array detector and mass spectrometry detector was developed, validated and implemented for determining Synephrine, Caffeine, Clenbuterol, Nandrolone, Testosterone and Methylhexaneamine in Nutritional supplements. The use of Nutritional supplements is widespread. Hazards relating to concentration, composition, individual contaminants, supplements interactions as well as positive doping results among athletes present increasing concerns regarding nutritional supplement consuming. The proposed method was validated according to the International Conference on the Harmonization of the Technical Requirements for Registration of Pharmaceuticals for Human Use (ICH) standards. The proposed method observed to be accurate, linear, precise, sensitive, required minimal sample preparation and uncomplicated mobile phase. The implementation of the proposed method on nine commercial supplements shows that inaccurate labeling for some supplements regarding the concentration of the ingredients.

Relationships between use of dietary supplements, caffeine and sensation seeking among college students

Objective: Caffeine and dietary supplement (DS) use by college students is not well-documented. Given reported associations between energy drink consumption and sensation seeking, we used the Sensation Seeking Scale Form V (SSS-V) to assess relationships between sensation-seeking, caffeine, and DS use. Participants: Data from 1,248 college students from five US institutions were collected from 2009 to 2011. Methods: Linear regression was used to examine relationships between scores on the SSS-V and caffeine and DS use, demographic, and lifestyle characteristics. Results: Male sex, nonHispanic race-ethnicity, higher family income, tobacco use, consuming caffeinated beverages, more than 400 mg caffeine per day, and energy drinks with alcohol at least 50% of the time, were significantly associated with higher total SSS-V scores (P < 0.001). Those using protein DSs had higher total, disinhibition, and boredom susceptibility SSS-V scores (Ps < 0.001). Conclusions: Results demonstrate a positive correlation between sensation-seeking attitudes and habitual caffeine, energy drink, and DS consumption.

Supplement Use and Behaviors of Athletes Affiliated With an Australian State-Based Sports Institute

The authors aimed to update knowledge of the use of supplements among Australian athletes at a state-based sports institute. The authors conducted a cross-sectional survey using an online questionnaire to assess the influence of age, sports category, and scholarship category on supplement use. Of 94 completed questionnaires, 82 (87%) indicated supplements in the previous 12 months (mean = 4.9 ± 3.3). No significant difference in supplement usage rate was identified when considering age, scholarship category, or sport category. The most frequently used supplements were sports drinks (70%), caffeine (48%), protein powder (42%), and sports bars (42%). Recovery (63%), health maintenance (59%), and improved energy (50%) were the most frequently reported rationale to use supplements. Allied health professionals and credible online resources were the predominant sources of influence regarding use. However, athletes from lower scholarship categories were more likely to have social media, parents, and siblings influence usage, and age was inversely related to increased influence from parents, social media, physicians not associated with the institute, the Internet, and siblings. Older athletes and those on higher scholarships were more likely to source supplements from training facilities and sports nutrition staff outside of the institute or direct from a supplier, whereas those on lower scholarships tended to rely more on family and friends for their supplements. Findings from this study show a high prevalence of supplement use and are the first to show an influence of social media, particularly in younger athletes. Opportunities exist to optimize how athletes are informed regarding supplement use and organizational and supplement policy.

Understanding the Use of Dietary Supplements among Athlete and Non-Athlete University Students: Development and Validation of a Questionnaire

BACKGROUND

The purpose of this study is to develop and test the validity and reliability of a questionnaire to evaluate dietary supplement use based on the Theory of Planned Behaviour (TPB).

METHODS

The questionnaire has sections on demographics, physical activity, dietary supplements, and cognitive constructs based on the TPB. Three stages are followed. In Stage 1, elicitation interviews are conducted on five varsity athletes, five physically active non-athletes, and five physically inactive University of Guelph (UofG) students. In Stage 2, comments and ratings of the TPB-based statements are gathered from 10 subject matter experts to check for content validity. In Stage 3, Cronbach's α is calculated to determine the internal consistency of the cognitive constructs by a pilot test on 84 Applied Human Nutrition UofG students.

RESULTS

Interviews assisted in the formulation of the cognitive constructs' statements, including intentions, attitudes, injunctive norms, descriptive norms, and perceived behavioural control. Content validity ensured that these constructs did not overlap. Few statements from the cognitive constructs were omitted based on findings from the reliability test, achieving acceptable Cronbach's α values across all constructs (≥0.70).

CONCLUSIONS

This supplement use questionnaire will be used in a future study to investigate the use and determinants of dietary supplements among Canadian athlete and non-athlete UofG students.

Prevalence, knowledge and attitudes towards using sports supplements among young athletes

Background

The aim of this international study was to investigate the prevalence of the use of sports supplements among young athletes, as well as their knowledge and attitudes towards sports supplementation.

Methods

Organized survey study testing the level of knowledge, attitudes, beliefs and practices concerning the use of sports supplements was administered to 348 athletes, 15–18 year olds from 4 countries competing in 18 sports at the international level.

Results

The prevalence rate of the intake of sports supplements was 82.2%, with the protein supplements being predominant (54.5%). Coaches were identified as the primary source of information regarding supplementation (41.4%). The enhancement of athletic performance (35.4%) was the major motivation for the supplements intake. The majority of athletes (72.1%) were aware of associated health risks. The young athletes possess varying levels of knowledge regarding their own supplementation. The obtained data about the level of knowledge were statistically analyzed using the correspondence analysis. Less than 40% of athletes had the knowledge about the proper and intended use of protein, creatine, amino acids, beta alanine and glutamine, while they had greater understanding about vitamins and minerals, sports drinks and caffeine. The athletes in developed countries had greater access and utilization of professional resources such as dieticians. Young athletes are still unfamiliar with WADA regulations (55.5%), and the misuse of sports supplements represents an ethical dilemma for some.

Conclusion

These findings indicate the necessity of a comprehensive education of all team members about sports supplements and careful supervision of the athletic development of young athletes.

Electronic supplementary material

The online version of this article (10.1186/s12970-019-0294-7) contains supplementary material, which is available to authorized users.

Evaluation of Dietary Supplement Use in Wheelchair Rugby Athletes

Wheelchair rugby is a rapidly growing Paralympic sport; however, research remains predominantly in the realms of physiology and biomechanics. Currently, there is little investigation into nutrition and dietary supplement use among wheelchair rugby athletes (WRA). The aim of this study was to assess the types of dietary supplements (DS) used, the prevalence of usage, and the reasons for use among WRA. The secondary aim was to report utilized and preferred sources of nutritional information among this population. A valid, reliable Dietary Supplement Questionnaire was used to report supplement use and reasons for use. Male (n = 33) and female (n = 9) WRA were recruited at a national tournament and through emailing coaches of various Canadian teams. Dietary supplement usage was prevalent as 90.9% of males and 77.8% of females reported usage within the past three months with the most regularly used supplements being vitamin D (26.2%), electrolytes (19.5%), and protein powder (19.5%). The most common reason for usage was performance. The top sources of nutrition information were dietitian/nutritionist and the internet. Further investigation into DS use is needed to help create nutritional guidelines that are accessible to WRA and athletes with disabilities in general.

Athletes and Supplements: Prevalence and Perspectives

In elite sport, where opponents are evenly matched, small factors can determine the outcome of sporting contests. Not all athletes know the value of making wise nutrition choices, but anything that might give a competitive edge, including dietary supplements, can seem attractive. Between 40% and 100% of athletes typically use supplements, depending on the type of sport, level of competition, and the definition of supplements. However, unless the athlete has a nutrient deficiency, supplementation may not improve performance and may have a detrimental effect on both performance and health. Dietary supplements are classified as a subcategory of food, so manufacturers are not required to provide evidence of product safety and efficacy, nor obtain approval from regulatory bodies before marketing supplements. This creates the potential for health risks, and serious adverse effects have been reported from the use of some dietary supplements. Athletes who compete in sports under an anti-doping code must also realize that supplement use exposes them to a risk of ingesting banned substances or precursors of prohibited substances. Government systems of regulations do not include specific laboratory testing for banned substances according to the WADA list, so a separate regulatory framework to evaluate supplements for their risk of provoking a failed doping test is needed. In the high-performance culture typical of elite sport, athletes may use supplements regardless of possible risks. A discussion around medical, physiological, cultural, and ethical questions may be warranted to ensure that the athlete has the information needed to make an informed choice.

Evaluation of Dietary Intakes and Supplement Use in Paralympic Athletes

Dietary intakes and supplement use in Paralympic athletes remains largely unexplored, and specialized recommendations are lacking. The aim of this study was to evaluate nutrient intakes and supplement use in high-performance athletes with physical disabilities using three-day food records and a validated dietary supplement use questionnaire. A secondary aim examined gender differences in nutrient and supplement intakes. Male (n = 18) and female (n = 22) athletes were recruited from nine Paralympic sports through sporting organizations, coaches, and social media. Athletes generally met able-bodied recommendations for macronutrients. Male and female athletes often failed to meet the Recommended Dietary Allowance (RDA) or Adequate Intake (AI) for vitamin D, vitamin E, pantothenic acid, magnesium, and potassium. On average, females did not meet the RDA for iron and calcium, whereas males did not meet the RDA for vitamin A and folate. Commonly consumed supplements were vitamin D, protein powder, sport bars, and sport drinks. Analysis of diet and supplement use within this population shows several micronutrient deficiencies and irregular use of specific supplements. Athlete support and education is required to optimize nutrition in Paralympic athletes.

Do Bodybuilders Use Evidence-Based Nutrition Strategies to Manipulate Physique?

Competitive bodybuilders undergo strict dietary and training practices to achieve an extremely lean and muscular physique. The purpose of this study was to identify and describe different dietary strategies used by bodybuilders, their rationale, and the sources of information from which these strategies are gathered. In-depth interviews were conducted with seven experienced (10.4 ± 3.4 years bodybuilding experience), male, natural bodybuilders. Participants were asked about training, dietary and supplement practices, and information resources for bodybuilding strategies. Interviews were transcribed verbatim and analyzed using qualitative content analysis. During the off-season, energy intake was higher and less restricted than during the in-season to aid in muscle hypertrophy. There was a focus on high protein intake with adequate carbohydrate to permit high training loads. To create an energy deficit and loss of fat mass, energy intake was gradually and progressively reduced during the in-season via a reduction in carbohydrate and fat intake. The rationale for weekly higher carbohydrate refeed days was to offset declines in metabolic rate and fatigue, while in the final “peak week” before competition, the reasoning for fluid and sodium manipulation and carbohydrate loading was to enhance the appearance of leanness and vascularity. Other bodybuilders, coaches and the internet were significant sources of information. Despite the common perception of extreme, non-evidence-based regimens, these bodybuilders reported predominantly using strategies which are recognized as evidence-based, developed over many years of experience. Additionally, novel strategies such as weekly refeed days to enhance fat loss, and sodium and fluid manipulation, warrant further investigation to evaluate their efficacy and safety.

[Nutritional supplements in sports - sense, nonsense or hazard?]

The excessive sale of dietary supplements (DSs) has become a global multi-billion market as more and more people turn to DSs for a healthy lifestyle or for aesthetic reasons. DSs are also increasingly popular among athletes; 50-85% of recreational and 35-100% of competitive athletes report taking DSs, the latter more regularly. Unless pathological deficiencies are detected, the intake of DSs for recreational athletes is not recommended. While it may be advisable for competitive athletes to supplement their diet with certain macronutrients (proteins and carbohydrates), many micronutrients (vitamins, minerals) as well as allegedly performance enhancing DSs may only show minimal impact under specific conditions and for certain sports. However, most products lack proof of their effectiveness. In some cases, DSs may even have negative effects and reduce performance. Furthermore, competitive athletes should be aware of the fact that DSs may lead to positive doping tests, as they bear the risk of being contaminated with banned substances, or components may be banned substances themselves. Every single case of taking DSs should therefore be critically assessed and discussed with experts prior to use. DSs cannot replace a balanced diet and hard practice.

FATORES ASSOCIADOS AO USO DE SUPLEMENTOS ALIMENTARES ENTRE ATLETAS: REVISÃO SISTEMÁTICA

RESUMO A prevalência de consumo de suplementos alimentares entre atletas tem sido estudada exaustivamente. Contudo, não foi encontrado estudo que reúna e discuta, de forma sistematizada, os fatores que podem desencadear o consumo de suplementos entre atletas. O objetivo foi descrever a prevalência e as características do consumo e compreender quais fatores estão associados ao uso dos suplementos alimentares nessa população específica. Realizou-se uma pesquisa bibliográfica nas seguintes bases de dados: PubMed, Lilacs e Scielo. O Google Scholar foi consultado para identificação de material adicional. Foram incluídos estudos que investigaram a prevalência do uso de suplementos alimentares entre atletas, seus fatores associados, sem limite de idade e em ambos os sexos. De 374 estudos identificados, dezessete foram incluídos nesta revisão. Todos os estudos utilizaram delineamento transversal e o instrumento de coleta mais utilizado foi o questionário autoadministrado. A prevalência do uso de suplementos variou de 37,5% a 98%. Os atletas têm consumido mais vitaminas buscando informações com seus técnicos, visando melhorar o estado geral de saúde. "Prática de esporte individual" e "alto volume de treinamento" foram identificados como fatores associados ao uso de suplementos alimentares. A partir dos dados revisados, verificou-se um amplo intervalo de variação na utilização de suplementos pelos atletas. Os atletas têm consumido mais vitaminas e procuraram informações sobre o consumo com seus treinadores, com o objetivo de melhorar a sua saúde. Esta revisão também destaca a necessidade de uma investigação de alta qualidade sobre os correlatos de consumo de suplemento em atletas, uma vez que os dados foram discrepantes para muitos fatores relatados pelos estudos.

Knowledge, Attitudes and Practices (KAP) Relating to Dietary Supplements Among Health Sciences and Non-Health Sciences Students in One of The Universities of United Arab Emirates (UAE)

INTRODUCTION

The use of Dietary Supplements (DS) has increased substantially in the United Arab Emirates (UAE) in recent years, despite the fact that the efficacy and safety of these supplements are not proven yet. In addition, the practices of supplement users in the UAE remain undocumented.

AIM

To determine the usage of DS in health sciences and non-health sciences students; and to determine their knowledge, attitudes and practices (KAP) regarding these supplements.

MATERIALS AND METHODS

A descriptive, cross-sectional, questionnaire-based study was conducted among university students. Based on the Raosoft online calculator, it was anticipated that the sample of 383 students would enable us to achieve the study objectives. Students were recruited from Ajman University of Science and Technology and identified by the academic staff through students' records. All students who were registered at Ajman University of Science and Technology - including medical (i.e. dental, pharmacy and health sciences) and non-medical colleges (i.e. engineering, business administration, law, information technology, mass communications and humanities) - were invited to participate, after obtaining the approval of the Institutional Ethics Committee (IEC), (during the period of January-February 2015). This study used quantitative method approach. Therefore, data were analysed quantitatively using SPSS version 22.0.

RESULTS

More than one-third of participants (39%) were found to consume DS. The most common reasons for consuming supplements were to maintain good health (58,21%) and ensure adequate nutrition (43,15%). Almost two-thirds of participants (65%) perceived that the best way to obtain nutrients is through food and DS together (49%), or DS alone (16%). Therefore, there was a relatively high amount of DS intake among participants in this study. With regard to medical and non-medical students' use of DS, there were no significant differences in the use (p=0.139). However, other findings suggest that there are significant differences in the knowledge of health sciences and non-health sciences students pertaining to the health benefits and safety of these supplements (p<0.001), what they are (p=0.040) and the source of help that should be sought when using them (p<0.001).

CONCLUSION

There is a relatively high prevalence of DS consumption among students, which they reported as using to maintain good health and ensure adequate nutrition. However, findings suggest that there are significant differences in the knowledge of health sciences and non-health sciences students pertaining to the health benefits and safety of these supplements. Therefore, awareness of DS usage and information should be integrated into everyday practice.

Improvements in Cycling but Not Handcycling 10 km Time Trial Performance in Habitual Caffeine Users

Caffeine supplementation during whole-/lower-body exercise is well-researched, yet evidence of its effect during upper-body exercise is equivocal. The current study explored the effects of caffeine on cycling/handcycling 10 km time trial (TT) performance in habitual caffeine users. Eleven recreationally trained males (mean (SD) age 24 (4) years, body mass 85.1 (14.6) kg, cycling/handcycling peak oxygen uptake (V·_peak) 42.9 (7.3)/27.6 (5.1) mL∙kg∙min⁻¹, 160 (168) mg/day caffeine consumption) completed two maximal incremental tests and two familiarization sessions. During four subsequent visits, participants cycled/handcycled for 30 min at 65% mode-specific V·_peak (preload) followed by a 10 km TT following the ingestion of 4 mg∙kg⁻¹ caffeine (CAF) or placebo (PLA). Caffeine significantly improved cycling (2.0 (2.0)%; 16:35 vs. 16:56 min; p = 0.033) but not handcycling (1.8 (3.0)%; 24:10 vs. 24:36 min; p = 0.153) TT performance compared to PLA. The improvement during cycling can be attributed to the increased power output during the first and last 2 km during CAF. Higher blood lactate concentration (Bla) was reported during CAF compared to PLA (p < 0.007) and was evident 5 min post-TT during cycling (11.2 ± 2.6 and 8.8 ± 3.2 mmol/L; p = 0.001) and handcycling (10.6 ± 2.5 and 9.2 ± 2.9 mmol/L; p = 0.006). Lower overall ratings of perceived exertion (RPE) were seen following CAF during the preload (p < 0.05) but not post-TT. Lower peripheral RPE were reported at 20 min during cycling and at 30 min during handcycling, and lower central RPE was seen at 30 min during cycling (p < 0.05). Caffeine improved cycling but not handcycling TT performance. The lack of improvement during handcycling may be due to the smaller active muscle mass, elevated (Bla) and/or participants’ training status.

Prevalence, knowledge and attitudes relating to β-alanine use among professional footballers

OBJECTIVES

To investigate β-alanine supplementation use and level of knowledge amongst professional footballers.

DESIGN

Cross-sectional survey of Australian professional football players.

METHODS

Questionnaires assessing β-alanine supplementation behaviours, level of knowledge and sources of information were completed by professional rugby union (RU) (n=87), rugby league (RL) (n=180) and Australian Rules Football (ARF) (n=303) players.

RESULTS

Approximately 61% of athletes reported β-alanine use, however use by ARF football players (44%) was lower than that of RU (80%) and RL players (80%). The majority of respondents were not using β-alanine in accordance with recommendations. Only 35% of the participants were able to correctly identify the potential benefits of β-alanine supplementation. The main information sources that influenced players' decision to use β-alanine were strength and conditioning coach (71%) and dietitian (52%). Forty-eight per cent of athletes never read labels prior to supplementing and only 11% completed their own research on β-alanine. Compared to RL and ARF players, RU players had both a greater knowledge of β-alanine supplementation and better supplementation practices.

CONCLUSIONS

Despite over half the surveyed professional footballers using β-alanine, the majority of athletes used β-alanine in a manner inconsistent with recommendations. A better understanding of the environment and culture within professional football codes is required before supplement use becomes consistent with evidence based supplement recommendations.

Nutrition Knowledge and Practices of Varsity Coaches at a Canadian University

PURPOSE

Coaches' sports nutrition knowledge and subsequent nutrition recommendations can have an impact on athletes' health and performance. The purpose of this study was to determine sports nutrition knowledge and nutrition recommendation practices of varsity coaches at one Canadian university and to determine if the coaches' nutrition knowledge influenced nutrition recommendations to athletes. The coaches' accessibility to sports dietitians was also examined.

METHODS

Coaches (n = 5) completed a modified psychometrically validated nutrition knowledge questionnaire and a semi-structured interview. Mean scores were calculated for questionnaire answers based on the correct answer and the coach's degree of certainty in their answer. Interviews were analyzed using thematic analysis.

RESULTS

Results showed a low nutrition knowledge, yet all coaches made nutrition recommendations to their athletes for fluid needs, dietary supplementation, and weight management; areas that may be potentially detrimental to the health of athletes. In addition, they made recommendations with regard to fluid needs, training diet, precompetition diet, recovery diet (i.e., post training or competition), dietary supplementation, and weight management; areas that could have potentially negative performance consequences to the athlete.

CONCLUSIONS

It was determined that coaches had low nutrition knowledge scores and still made nutrition recommendations to athletes. The importance of sports dietitian involvement in varsity athletics is emphasized.

Assessing Intentions to Eat a Healthful Diet Among National Collegiate Athletic Association Division II Collegiate Athletes

CONTEXT

Many athletes fail to obtain the optimal levels of energy and nutrients to support health and performance. The constructs underlying the Theory of Planned Behavior (TPB) may help identify barriers to healthful eating that can be addressed in nutrition-education programs.

OBJECTIVE

To use the TPB to examine factors regarding collegiate male and female student-athletes' intentions of eating a healthful diet.

DESIGN

Cross-sectional study.

SETTING

Online survey tool.

PATIENTS OR OTHER PARTICIPANTS

The survey was taken by 244 male and female National Collegiate Athletic Association Division II athletes, and data from 201 were analyzed. Mean age of the athletes was 20 ± 1.31 years (range, 18-24 years); most were white (86.1%) and female (78.6%).

MAIN OUTCOME MEASURE(S)

We assessed predictive strength of attitude, subjective norms, and perceived behavioral control on behavioral intentions. Regression analysis evaluated how the variables of TPB were valued and how they predict behavioral intentions.

RESULTS

The combination of attitude, subjective norms, and perceived behavioral controls accounted for 73.4% (R 2) of the variance in behavioral intention (F = 180.82, P < .001). Attitude had the greatest influence on behavioral intentions (β = .534, P < .001).

CONCLUSIONS

Understanding both the intentions of collegiate athletes to eat healthfully and how highly they value nutrition is crucial for the development of effective nutrition education and counseling programs.

Prevalence of Dietary Supplement Use by Athletes: Systematic Review and Meta-Analysis

BACKGROUND

Dietary supplements (DSs) are commercially available products consumed as an addition to the usual diet and are frequently ingested by athletes.

OBJECTIVE

Our objective was to examine the prevalence of DS use by athletes.

DATA SOURCES

PubMed, Ovid MEDLINE, OVID Healthstar, and Cumulative Index to Nursing and Allied Health were searched for original research articles published up to August 2014. Search terms included specific sports, specific DSs, and other terms.

STUDY SELECTION

Studies were selected if they were written in English, involved athletes, and provided a quantitative assessment of the proportion of athletes using specific DSs. Percent of athletes using specific DSs.

SYNTHESIS OF DATA

Methodological quality of studies was assessed by three reviewers using an 8-point scale that included evaluations for sampling methods, sampling frame, sample size, measurement tools, bias, response rate, statistical presentation, and description of the participant sample. Where there were at least two investigations, meta-analysis was performed to obtain summary (pooled) prevalence estimates (SPEs) on (1) DS use prevalence by sport and sex, (2) DS use prevalence by elite versus non-elite athletic status, and (3) specific DS prevalence for all athletic groups combined. Meta-analyses included evaluations of homogeneity and publication bias.

RESULTS

A total of 159 unique studies met the review criteria. Methodological quality was generally low with an average ± standard deviation of 43 ± 16% of available rating points. There was low homogeneity for SPEs when compiled by sport, athletic status, and/or specific DSs. Contributing to the lack of homogeneity were differences in studies' objectives and types of assessments used (e.g., dietary surveys, interviews, questionnaires). Despite these limitations, the data generally indicated that elite athletes used DSs much more than their non-elite counterparts. For most DSs, use prevalence was similar for men and women except that a larger proportion of women used iron while a larger proportion of men used vitamin E, protein, and creatine. No consistent change in use over time was observed because even the earliest investigations showed relatively high use prevalence.

CONCLUSION

It was difficult to generalize regarding DS use by athletes because of the lack of homogeneity among studies. Nonetheless, the data suggested that elite athletes used dietary supplements far more than their non-elite counterparts; use was similar for men and women with a few exceptions; use appeared to change little over time; and a larger proportion of athletes used DSs compared with the general US population. Improvements in study methodology should be considered in future studies especially (1) defining DSs for participants; (2) querying for very specific DSs; (3) using a variety of reporting timeframes (e.g., daily, 2-6 times/week, 1 time/week and <1 time/week); (4) reporting the sampling frame, number of individuals solicited, and number responding; (5) reporting characteristics of volunteers (and non-volunteers, if available); and (6) using similar methods on several occasions to examine possible temporal trends among athletes.

A Lifetime Pursuit of a Sports Nutrition Practice

Sports nutrition in Canada has significantly evolved over the years from providing fundamental training dietary advice to applied precise assessment of nutritional status in a variety of settings, especially with the establishment of Canadian Sport Institutes and Centres across Canada. This progression has enhanced the level of dietary support to manage athletes' nutrition in a holistic perspective. Athletes are now educated about food fundamentals (acquiring foods, menu planning, preparing, food safety), personal accountability of hydration and energy monitoring (urinary and body weight assessments), individualized supplementation protocols, and customized nutrition for variable daily training environments according to their Yearly Training Plan. Sport dietitians are an important member of Integrated Sport Teams where collaboration exists amongst professionals who coordinate the athletes' personalized training and performance programming. Dietitians in sport are encouraged to continue to lobby for nutrition programming at the elite, varsity, provincial, and club levels to ensure that athletes receive accurate guidance from nutrition experts.

Predictors of Dietary Supplement Use by U.S. Coast Guard Personnel

Background

Personnel in Armed Forces entities such as the US Coast Guard (USCG) engage in strenuous tasks requiring high levels of physiological and psychological fitness. Previous reports have found increased prevalence of dietary supplement (DS) use by military personnel to meet the demands of their occupation.

Objective

This study assessed DS prevalence and patterns of use in USCG personnel and compared these findings to reports from other Armed Forces personnel.

Design

Use of DS by USCG personnel (n = 1059) was assessed by survey at USCG installations. Data were weighted by age, sex, and rank to be representative of total USCG demographics.

Results

Seventy percent of USCG personnel reported using a DS at least 1 time/wk. Thirty-three percent used 1–2 DS ≤ 1 time/wk, 18% 3–4 DS ≥ 1 time/wk, and almost 19% ≥ 5 DS ≥ 1 time/wk. Average expenditure on DSs by UCSG personnel was $40/mo. More than 47% of USCG personnel used a multivitamin and mineral, 33% consumed protein supplements, 22% used individual vitamins and minerals, 23% reported taking combination products, and 9% consumed herbal supplements. Increased use of DS use was associated with high intensity operational occupations, participating in high volumes of aerobic exercise and strength training. Use of DS was not associated with age, education or body mass index.

Conclusion

Occupation is an important determinate of DS use. Prevalence of DS use by USCG personnel is greater than reported for other Armed Forces personnel and reflects high levels of participation in aerobic and strength training activities.

The effects of protein supplements on muscle mass, strength, and aerobic and anaerobic power in healthy adults: a systematic review

BACKGROUND

Protein supplements are frequently consumed by athletes and recreationally active adults to achieve greater gains in muscle mass and strength and improve physical performance.

OBJECTIVE

This review provides a systematic and comprehensive analysis of the literature that tested the hypothesis that protein supplements accelerate gains in muscle mass and strength resulting in improvements in aerobic and anaerobic power. Evidence statements were created based on an accepted strength of recommendation taxonomy.

DATA SOURCES

English language articles were searched through PubMed and Google Scholar using protein and supplements together with performance, exercise, strength, and muscle, alone or in combination as keywords. Additional articles were retrieved from reference lists found in these papers.

STUDY SELECTION

Studies recruiting healthy adults between 18 and 50 years of age that evaluated the effects of protein supplements alone or in combination with carbohydrate on a performance metric (e.g., one repetition maximum or isometric or isokinetic muscle strength), metrics of body composition, or measures of aerobic or anaerobic power were included in this review. The literature search identified 32 articles which incorporated test metrics that dealt exclusively with changes in muscle mass and strength, 5 articles that implemented combined resistance and aerobic training or followed participants during their normal sport training programs, and 1 article that evaluated changes in muscle oxidative enzymes and maximal aerobic power.

STUDY APPRAISAL AND SYNTHESIS METHODS

All papers were read in detail, and examined for experimental design confounders such as dietary monitoring, history of physical training (i.e., trained and untrained), and the number of participants studied. Studies were also evaluated based on the intensity, frequency, and duration of training, the type and timing of protein supplementation, and the sensitivity of the test metrics.

RESULTS

For untrained individuals, consuming supplemental protein likely has no impact on lean mass and muscle strength during the initial weeks of resistance training. However, as the duration, frequency, and volume of resistance training increase, protein supplementation may promote muscle hypertrophy and enhance gains in muscle strength in both untrained and trained individuals. Evidence also suggests that protein supplementation may accelerate gains in both aerobic and anaerobic power.

LIMITATIONS

To demonstrate measureable gains in strength and performance with exercise training and protein supplementation, many of the studies reviewed recruited untrained participants. Since skeletal muscle responses to exercise and protein supplementation differ between trained and untrained individuals, findings are not easily generalized for all consumers who may be considering the use of protein supplements.

CONCLUSIONS

This review suggests that protein supplementation may enhance muscle mass and performance when the training stimulus is adequate (e.g., frequency, volume, duration), and dietary intake is consistent with recommendations for physically active individuals.

Use of supplements by Japanese elite athletes for the 2012 Olympic Games in London

OBJECTIVE

To investigate supplement use among Japanese elite athletes.

DESIGN

We conducted a cross-sectional survey study using individual interviews during athletes' medical evaluations.

SETTING

One to 5 months before the Olympic Games in 2012, London, United Kingdom.

PARTICIPANTS

Five hundred fifty-two Japanese athletes for the London Games, including candidates.

INDEPENDENT VARIABLES

Sex, sports, supplement category, and participation.

MAIN OUTCOME MEASURES

Whether athletes used supplements, what products were used, the frequency and purposes of use, and from what sources athletes received information on supplements.

RESULTS

All 552 athletes were interviewed by pharmacists regarding supplement use and agreed to the survey. Of them, 452 (81.9%) used 1 or more supplement products in the year before the study; a total of 952 different products (mean = 1.7, SD = 1.4) were used. The most commonly used supplement was amino acids (310 athletes; 56.2%), and 358 (38.7%) of the total products were amino acids. Of the athletes, 241 (43.7%) took at least 1 supplement daily, and of the supplements, 457 (49.4%) were taken daily. The most common purpose for supplement use was recovery from fatigue-327 (59.2%) athletes chose this answer, and 486 (52.5%) products were used for this purpose. Finally, regarding athletes' information sources on supplements, coaches, managers, and trainers were the most frequent advisors (275 athletes, 49.8%; 466 products, 50.4%).

CONCLUSIONS

The results revealed widespread supplement use among Japanese elite athletes for the London Olympic Games. Education system was required not only for athletes but also for athletes' entourage, such as coaches, managers, trainers, and supplement companies.

CLINICAL RELEVANCE

This study will provide basic data for establishing an education system that would better guide athletes' use of supplements.

The estimation of mineral contents in oriental supplements consumed by elite athletes

The purpose of this study is twofold: to examine macro (calcium, magnesium, and phosphorus) and trace mineral (iron) concentration in oriental supplements (OS), and to define OS prevalence in elite athletes. Participants of this study were 928 varsity athletes (male: 680, female: 248) with 23 sports types. Recent 3-month dietary supplements (DS) and OS practice was surveyed during training period, and mineral concentration in 72 randomly collected OS samples were analyzed. DS use was 41% and OS use was 20% in university elite athletes. Most common OS use informants were parents (74%). OS intake reason was for health maintenance (37%), energy supplement (25%), and recovery improvement (15%). Moreover, health maintenance was higher in females (47%) than males (32%) while energy supplement was higher in males (28%) than females (18%) (χ(2)(8) = 17.676, p = 0.024). Beliefs in OS efficacy and importance were significantly higher in female athletes compared to male athletes (p < 0.05). Macro mineral concentration in OS was calcium (7.54 ppm), magnesium (4.63 ppm), and phosphorus (205.34 ppb) and trace mineral concentration in OS was iron (8.10 ppb), which was a small amount. An association between OS intake reason and mineral concentration in calcium, phosphorus, and iron was found, but no association between OS intake and magnesium. In conclusion, an association between OS intake reason and mineral concentration differed by the ingredients. Minerals in OS were very small amount, which would be improved for mineral balance in elite athletes.

Effects of protein in combination with carbohydrate supplements on acute or repeat endurance exercise performance: a systematic review

BACKGROUND

Protein supplements are consumed frequently by athletes and recreationally active adults for various reasons, including improved exercise performance and recovery after exercise. Yet, far too often, the decision to purchase and consume protein supplements is based on marketing claims rather than available evidence-based research.

OBJECTIVE

The purpose of this review was to provide a systematic and comprehensive analysis of the literature that tested the hypothesis that protein supplements, when combined with carbohydrate, directly enhance endurance performance by sparing muscle glycogen during exercise and increasing the rate of glycogen restoration during recovery. The analysis was used to create evidence statements based on an accepted strength of recommendation taxonomy.

DATA SOURCES

English language articles were searched with PubMed and Google Scholar using protein and supplements together with performance, exercise, competition, and muscle, alone or in combination as keywords. Additional articles were retrieved from reference lists found in these papers.

STUDY SELECTION

Inclusion criteria specified recruiting healthy active adults less than 50 years of age and evaluating the effects of protein supplements in combination with carbohydrate on endurance performance metrics such as time-to-exhaustion, time-trial, or total power output during sprint intervals. The literature search identified 28 articles, of which 26 incorporated test metrics that permitted exclusive categorization into one of the following sections: ingestion during an acute bout of exercise (n = 11) and ingestion during and after exercise to affect subsequent endurance performance (n = 15). The remaining two articles contained performance metrics that spanned both categories.

STUDY APPRAISAL AND SYNTHESIS METHODS

All papers were read in detail and searched for experimental design confounders such as energy content of the supplements, dietary control, use of trained or untrained participants, number of subjects recruited, direct measures of muscle glycogen utilization and restoration, and the sensitivity of the test metrics to explain the discrepant findings.

RESULTS

Our evidence statements assert that when carbohydrate supplementation was delivered at optimal rates during or after exercise, protein supplements provided no further ergogenic effect, regardless of the performance metric used. In addition, the limited data available suggested recovery of muscle glycogen stores together with subsequent rate of utilization during exercise is not related to the potential ergogenic effect of protein supplements.

LIMITATIONS

Many studies lacked ability to measure direct effects of protein supplementation on muscle metabolism through determination of muscle glycogen, kinetic assessments of protein turnover, or changes in key signaling proteins, and therefore could not substantiate changes in rates of synthesis or degradation of protein. As a result, the interpretation of their data was often biased and inconclusive since they lacked ability to test the proposed underlying mechanism of action.

CONCLUSIONS

When carbohydrate is delivered at optimal rates during or after endurance exercise, protein supplements appear to have no direct endurance performance enhancing effect.

Effects of protein supplements on muscle damage, soreness and recovery of muscle function and physical performance: a systematic review

BACKGROUND

Protein supplements are frequently consumed by athletes and recreationally-active individuals, although the decision to purchase and consume protein supplements is often based on marketing claims rather than evidence-based research.

OBJECTIVE

To provide a systematic and comprehensive analysis of literature examining the hypothesis that protein supplements enhance recovery of muscle function and physical performance by attenuating muscle damage and soreness following a previous bout of exercise.

DATA SOURCES

English language articles were searched with PubMed and Google Scholar using protein and supplements together with performance, exercise, competition and muscle, alone or in combination as keywords.

STUDY SELECTION

Inclusion criteria required studies to recruit healthy adults less than 50 years of age and to evaluate the effects of protein supplements alone or in combination with carbohydrate on performance metrics including time-to-exhaustion, time-trial or isometric or isokinetic muscle strength and markers of muscle damage and soreness. Twenty-seven articles were identified of which 18 dealt exclusively with ingestion of protein supplements to reduce muscle damage and soreness and improve recovery of muscle function following exercise, whereas the remaining 9 articles assessed muscle damage as well as performance metrics during single or repeat bouts of exercise.

STUDY APPRAISAL AND SYNTHESIS METHODS

Papers were evaluated based on experimental design and examined for confounders that explain discrepancies between studies such as dietary control, training state of participants, sample size, direct or surrogate measures of muscle damage, and sensitivity of the performance metric.

RESULTS

High quality and consistent data demonstrated there is no apparent relationship between recovery of muscle function and ratings of muscle soreness and surrogate markers of muscle damage when protein supplements are consumed prior to, during or after a bout of endurance or resistance exercise. There also appears to be insufficient experimental data demonstrating ingestion of a protein supplement following a bout of exercise attenuates muscle soreness and/or lowers markers of muscle damage. However, beneficial effects such as reduced muscle soreness and markers of muscle damage become more evident when supplemental protein is consumed after daily training sessions. Furthermore, the data suggest potential ergogenic effects associated with protein supplementation are greatest if participants are in negative nitrogen and/or energy balance.

LIMITATIONS

Small sample numbers and lack of dietary control limited the effectiveness of several investigations. In addition, studies did not measure the effects of protein supplementation on direct indices of muscle damage such as myofibrillar disruption and various measures of protein signaling indicative of a change in rates of protein synthesis and degradation. As a result, the interpretation of the data was often limited.

CONCLUSIONS

Overwhelmingly, studies have consistently demonstrated the acute benefits of protein supplementation on post-exercise muscle anabolism, which, in theory, may facilitate the recovery of muscle function and performance. However, to date, when protein supplements are provided, acute changes in post-exercise protein synthesis and anabolic intracellular signaling have not resulted in measureable reductions in muscle damage and enhanced recovery of muscle function. Limitations in study designs together with the large variability in surrogate markers of muscle damage reduced the strength of the evidence-base.

Protein supplementation and dietary behaviours of resistance trained men and women attending commercial gyms: a comparative study between the city centre and the suburbs of Palermo, Italy

Background

It is anecdotally recognized that commercial gym users assume supplements in order to improve performance or health. However, dietary behaviours of people and athletes attending commercial gyms have been poorly studied. The exact amount and frequency of dietary supplements consumption are still needed to be investigated. The main purpose of this study is to understand the quantity and quality of food intake, as well as dietary supplementation in people attending commercial gyms. Secondly to compare the city centre and the suburbs of Palermo, Italy.

Methods

A face-to-face questionnaire was administered to 561 subjects, 207 from the city centre (CC) and 354 from the suburbs (SB) of Palermo, Italy. Frequency of protein supplements use and association with dietary behaviours were investigated. Subsequently, the frequency distribution was used for demographic assessment.

Results

Frequency of protein consumption was similar in both groups (30% for CC and 28.8% for SB). Males show greater consumption percentages than females (30.5% in males and 6.9% in females). Milk and chicken are the most frequently consumed foods. Data show that non-supplement users (NSU) consume significantly more snacks and bakery products than supplement users (SU) (P < 0.001). While, SU consume significantly higher quantities of vegetables, nuts, fresh fish, eggs and canned tuna (P < 0.001). SU consume less low protein food and higher protein foods than NSU. No differences were found between CC and SB.

Conclusions

Protein consumption among commercial gym users is 30% for the CC and 28.8% for the SB. Significant differences were found between CC and SB females, underlining an interesting discrepancy, indicating to dietary supplement industries regarding regional implications. Subjects that use protein supplements also consume larger quantities of high protein food compared to NSU. NSU also eat higher proportions of unhealthy food compared to SU.

Verification of efficacy as an ergogenic aid and safety in doping of sibjeondaebo-tang

[Purpose]

[Methods]

[Results]

[Conclusion]

Protein supplementation for military personnel: a review of the mechanisms and performance outcomes

Protein supplement use is common among athletes, active adults, and military personnel. This review provides a summary of the evidence base that either supports or refutes the ergogenic effects associated with different mechanisms that have been proposed to support protein supplementation. It was clear that if carbohydrate delivery was optimal either during or after an acute bout of exercise that additional protein will not increase exercise capacity. Evidence was also weak to substantiate use of protein supplements to slow the increase in brain serotonin and onset of central fatigue. It was also evident that additional research is warranted to test whether the benefits of protein supplements for enhancing recovery of fluid balance after exercise will affect subsequent work in the heat. In contrast, with repeated exercise, use of protein supplementation was associated with reductions in muscle soreness and often a faster recovery of muscle function due to reductions in protein degradation. There was also good supportive evidence for long-term benefits of protein supplementation for gains in muscle mass and strength through accelerated rates of protein synthesis, as long as the training stimulus was of sufficient intensity, frequency, and duration. However, studies have not examined the impact of protein supplements under the combined stress of a military environment that includes repeated bouts of exercise with little opportunity for feeding and recovery, lack of sleep, and exposure to extreme environments. Both additional laboratory and field research is warranted to help provide evidence-based guidance for the choice of protein supplements to enhance soldier performance.

Use of supplements by young elite Japanese athletes participating in the 2010 youth Olympic games in Singapore

OBJECTIVE

To investigate the prevalence of supplement use among young elite Japanese athletes.

DESIGN

Survey study.

SETTING

2010 Youth Olympic Games, Singapore.

PARTICIPANTS

Data were collected from individual interviews during medical evaluations of 75 athletes selected for the Japanese national team.

MAIN OUTCOME MEASURES

Main outcome measures included the use of supplements, products used, frequency of use, purpose of use, and relationships between supplement use and athlete attitudes toward a balanced diet.

RESULTS

All 75 athletes agreed to participate in this study, and individual interviews by pharmacists made it possible to collect complete answers from all athletes. Of these athletes, 47 (62.7%) used 1 or more supplement products (average number of products used, 1.1 ± 1.3). The most popular supplement was amino acids, which were used by 33 athletes (44.0%). Of the supplements used, 28 (32.6%) were taken every day, whereas 28 (32.6%) were used only on special occasions. Moreover, 34 of the supplement products (39.5%) were taken to enhance recovery from fatigue, whereas 19 (22.1%) were used to improve athletic performance. Statistical analysis suggested that there was no significant relationship between supplement use and attitudes toward a balanced diet.

CONCLUSIONS

The results revealed widespread supplement use among young elite athletes in the Japanese national team for the Singapore Youth Olympic Games in 2010. Moreover, these athletes apparently used supplements without considering the effects of their normal diets.

Intake of Nutritional Supplements among People Exercising in Gyms in Beirut City

The use of nutritional supplements among exercisers in gyms has been never investigated in the Middle East. The aim of the current study was to assess the prevalence intake of nutritional supplements and the potential influencing factors among people exercising in gyms in Beirut city. In this cross-sectional study, 512 exercisers, aged between 20 and 50 years, were randomly selected from gyms. The intake of nutritional supplements was reported among 36.3% (95% confidence interval 32.2–40.5) of participants, with a weak presence of medical supervision. Patterns of supplement use differed by gender and age. Men and younger exercisers were found to focus on supplements associated with performance enhancement and muscle building, while women and older exercisers were more concerned with health-promoting products such as vitamins, minerals, and herbal supplements. An appropriate dissemination of accurate and scientifically sound information regarding the benefits and side effects of nutritional supplements is highly recommended in the sports environment in Beirut city.

Anti-doping education and dietary supplementation practice in Korean elite university athletes

This study was conducted to investigate relationships and gender differences in dietary supplement (DS) and oriental supplement (OS) prevalence as well as anti-doping awareness during training and the game period. Korea National Sport University athletes (343 male and 136 female) participated in this study and completed DS and OS practice and anti-doping awareness questionnaires. Forty-six percent of athletes used DS during the training period, and there was significantly higher DS use in females (53%) compared to males (43%) (P < 0.05). Twenty-eight percent of athletes used OS, and there was significantly higher OS use in females (35%) than males (26%) (P < 0.05) during the training period. The primary reason of DS use was to supply energy both in males (36%) and females (28%). The main reason for male athletes' OS use was to supply energy (41%). Meanwhile, the reasons for female athletes' OS use were to supply energy (23%), to maintain health (19%), and to improve recovery ability (20%), which showed a significant gender difference (P < 0.05). Athletes rated their perceived degree of satisfaction, perceived importance, and beliefs in efficacy of DS and OS use all over 50% during the training period, and no gender differences were detected. In a comparison between athletes educated about anti-doping (at least more than one time) and non-received athletes, DS and OS use during the training period was 2.30 (1.47-3.60) and 1.71 (1.03-2.82), respectively. DS and OS use immediately before the game period was 2.38 (1.50-3.80) and 3.99 (1.20-13.28), respectively. Elite athletes' anti-doping education was highly related to increased DS use during the training period and immediately before the game. Although elite athletes use various DS and OS during the training period and before the game period, doping education for elite athletes is related with DS and OS use during the training period and before the game.

Gateway to doping? Supplement use in the context of preferred competitive situations, doping attitude, beliefs, and norms

Nutritional supplement (NS) use is widespread in sport. This study applied an integrated social cognitive approach to examine doping attitudes, beliefs, and self-reported doping use behavior across NS users (n = 96) and nonusers (n = 116). Following ethical approval, 212 competitive athletes (age mean = 21.4, s = 4.5; 137 males) completed self-reported measures of doping-related social cognitions and behaviors, presented in an online format where completion implied consent. Significantly more NS users (22.9%) reported doping compared with nonusers (6.0%; U = 4628.0, P < 0.05). NS users presented significantly more positive attitudes toward doping (U = 3152.0, P < 0.05) and expressed a significantly greater belief that doping is effective (U = 3152.0, P < 0.05). When presented with the scenario that performance-enhancing substances are effective and increase the possibility of winning, NS users were significantly more in favor of competing in situations that allow doping (U = 3504.5, P < 0.05). In sum, doping use is three-and-a-half times more prevalent in NS users compared with nonusers. This finding is accompanied by significant differences in doping attitudes, norms, and beliefs. Thus, this article offers support for the gateway hypothesis; athletes who engage in legal performance enhancement practices appear to embody an "at-risk" group for transition toward doping. Education should be appropriately targeted.

Evaluation of nutritional intake in Canadian high-performance athletes

OBJECTIVE

To determine the nutritional intake of Canadian high-performance athletes.

DESIGN

Prospective survey study.

SETTING

Canadian sport center athletes.

PARTICIPANTS

Three hundred twenty-four high-performance athletes (114 males and 201 females; mean age 21.3 +/- 13 years) from 8 Canadian sport centers participated in the study.

INTERVENTION

Subjects prospectively completed 3-day dietary records, reporting all food, fluid, and supplement consumption.

MAIN OUTCOME MEASURES

Dietary records were analyzed for total calories, macronutrients, and micronutrients for food alone and food plus supplements for all subjects collectively and according to gender and competitive event.

RESULTS

Average daily energy intake was 2533 +/- 843 Kcal/day with males consuming more calories than females (2918 +/- 927 and 2304 +/- 713 Kcal/day, respectively; P < 0.05). Both genders consumed below recommended levels. Carbohydrate, protein, and fat accounted for 53%, 19%, and 28% of daily calorie intake, respectively. Average daily carbohydrate and protein intake was 5.1 +/- 1.8 and 1.8 +/- 0.6 g/kg body weight, respectively. Protein intake, but not carbohydrate intake, met recommendations. Supplementation significantly increased athletes' energy, total carbohydrate, protein, and fat intake. Of 17 micronutrients assessed, intake ranged between 120% and 366% of recommended daily intake with food alone and between 134% to 680% of recommended daily intake with supplements.

CONCLUSIONS

Canadian high-performance athletes do not consume adequate energy or carbohydrates. However, their intake of micronutrients exceed current recommended daily intakes, even when supplements are not considered, indicating that athletes make high-quality food choices. Supplementation significantly increased energy, macronutrient, and micronutrient intake.

Nutritional supplements cross-contaminated and faked with doping substances

Since 1999 several groups have analyzed nutritional supplements with mass spectrometric methods (GC/MS, LC/MS/MS) for contaminations and adulterations with doping substances. These investigations showed that nutritional supplements contained prohibited stimulants as ephedrines, caffeine, methylenedioxymetamphetamie and sibutramine, which were not declared on the labels. An international study performed in 2001 and 2002 on 634 nutritional supplements that were purchased in 13 different countries showed that about 15% of the nonhormonal nutritional supplements were contaminated with anabolic-androgenic steroids (mainly prohormones). Since 2002, also products intentionally faked with high amounts of 'classic' anabolic steroids such as metandienone, stanozolol, boldenone, dehydrochloromethyl-testosterone, oxandrolone etc. have been detected on the nutritional supplement market. These anabolic steroids were not declared on the labels either. The sources of these anabolic steroids are probably Chinese pharmaceutical companies, which sell bulk material of anabolic steroids. In 2005 vitamin C, multivitamin and magnesium tablets were confiscated, which contained cross-contaminations of stanozolol and metandienone. Since 2002 new 'designer' steroids such as prostanozol, methasterone, androstatrienedione etc. have been offered on the nutritional supplement market. In the near future also cross-contaminations with these steroids are expected. Recently a nutritional supplement for weight loss was found to contain the beta2-agonist clenbuterol. The application of such nutritional supplements is connected with a high risk of inadvertent doping cases and a health risk. For the detection of new 'designer' steroids in nutritional supplements, mass spectrometric strategies (GC/MS, LC/MS/MS) are presented.

Performance enhancement with supplements: incongruence between rationale and practice

BACKGROUND

Athletes are expected to consider multiple factors when making informed decision about nutritional supplement use. Besides rules, regulations and potential health hazards, the efficacy of different nutritional supplements in performance enhancement is a key issue. The aim of this paper was to find evidence for informed decision making by investigating the relationship between specific performance-related reasons for supplement use and the reported use of nutritional supplements.

METHODS

The 'UK Sport 2005 Drug Free Survey' data (n = 874) were re-analysed using association [chi2] and 'strength of association' tests [varphi] to show the proportion of informed choices and to unveil incongruencies between self-reported supplement use and the underlying motives.

RESULTS

Participants (n = 520) reported supplement use in the pattern of: vitamin C (70.4%), creatine (36.1%), whey protein (30.6%), iron (29.8%), caffeine (23.8%), and ginseng (8.3%) for the following reasons: strength maintenance (38.1%), doctors' advice (24.2%), enhancing endurance (20.0%), ability to train longer (13.3%), and provided by the governing body (3.8%). Of thirty possible associations between the above supplements and reasons, 11 were predictable from literature precedents and only 8 were evidenced and these were not strong (varphi < .7). The best associations were for the ability to train longer with creatine (reported by 73.9%, chi2 = 49.14, p < .001; varphi = .307, p < .001), and maintaining strength with creatine (reported by 62.6%, chi2 = 97.08, p < .001; varphi = .432, p < .001) and whey protein (reported by 56.1%, chi2 = 97.82, p < .001; varphi = .434, p < .001).

CONCLUSION

This study provided a platform for assessing congruence between athletes' reasons for supplement use and their actual use. These results suggest that a lack of understanding exists in supplement use. There is an urgent need to provide accurate information which will help athletes make informed choices about the use of supplements.

Dietary supplementation of high-performance Canadian athletes by age and gender

OBJECTIVE

To determine dietary supplementation practices and opinions, preferred means for dietary supplement (DS) education, and antidoping opinions among elite Canadian athletes varying in age and gender.

DESIGN

A descriptive, cross-sectional survey.

SETTING

Elite athlete training centers in Calgary, Canada and surrounding area.

PARTICIPANTS

A total of 582 high-performance athletes (314 male, 268 female).

MAIN OUTCOME MEASURES

High-performance athletes representing 27 sports with a mean age of 19.96+/-3.91 years completed a validated questionnaire assessing DS practices and opinions by recall. Sport categories included varsity, Canadian Sport Centre Calgary (CSCC), and National Sport School (NSS).

RESULTS

There was extensive DS use, with 88.4% of participants taking>or=1 DS (mean of 3.08+/-1.87 DS per user) during the previous 6 months. Overall, sport drinks (22.4%), sport bars (14.0%), multivitamins and minerals (13.5%), protein supplements (9.0%), and vitamin C (6.4%) were most frequently reported. Older athletes were significantly more likely to report greater DS usage; to be advised by teammates, health food store retailers, and magazines; to prefer supplementation education via individual interviews; to claim awareness of anti-doping rules; and to perceive anti-doping compliance. Relative to gender, significant differences were observed for the types of DS reported; supplementation advisors; justifications for DS use; and awareness of anti-doping regulations.

CONCLUSIONS

Utilization of this validated and reliable questionnaire has the potential for broad use and provides insight into the factors that influence DS use in elite athletes.

Limited agreement exists between rationale and practice in athletes' supplement use for maintenance of health: a retrospective study

Background

The widespread use of nutritional supplements among athletes is poorly understood. The prevalence of supplement intake and users' knowledge have been researched independently leading to useful, but disconnected, information on supplement use.

Methods

The 'UK Sport 2005 Drug Free Survey' data (n = 874) were re-analysed using association [χ²] and 'strength of association' tests [φ], to discover observed incongruencies between self-reported supplement use and the underlying motives. Results are given for test pairs between 'motive for use' [doctor's advice, avoiding sickness, overcoming injuries and enhancement of diet] and each supplement used and these were categorized as strong (φ > .7), intermediate (7 < φ > .3) and weak (φ < .3).

Results

The use of selected supplements varied widely as follows: multivitamin (72.7%), vitamin C (70.4%), echinacea (30.8%), iron (29.8%), magnesium (11.0%) and ginseng (8.3%). Associations with motive were found in 8 of the 10 test pairs which were expected from literature precedents, however only weak associations exist. Of these, four were associated with avoidance of sickness [iron (χ² = 11.94, p < .001; φ = .15, p = .001), multivitamin (χ² = 6.43, p < .001; φ = .11, p = .011), vitamin C (χ² = 54.67, p < .001; φ = .32, p < .001) and echinacea (χ² = 40.34, p < .001; φ = .28, p < .001)]. The remaining 4 associations were: no time to prepare meals with ginseng (χ² = 7.64, p = .006; φ = .12, p = .006) and multivitamin (χ² = 9.103, p = .003; φ = .13, p = .003); overcoming injuries with magnesium (χ² = 6.99, p = .008; φ = .11, p = .008); doctors' advice and iron (χ² = 35.00, p < .001; φ = .25, p = .001).

Conclusion

These results suggest a lack of understanding regarding supplements and health maintenance, except for vitamin C and echinacea. Furthermore, supplement use is apparently independent of physicians/dieticians' advice, except for iron. This may suggest a widespread circumvention of expert advice in the growing area of supplement use and therefore should be addressed to underscore potential health risks.