Supplement use and nutritional habits in Norwegian elite athletes

Nutritional Values of Foods on a Population of the Czech Republic

The aim of this text is to present the results of the research we carried out on a group of inhabitants of the Czech Republic who actively (or at least occasionally) engage in sports activities. The aim of the research was to analyse the consumer behavior of athletes in the Czech Republic with an emphasis on their use of health food stores and their habits in monitoring the nutritional values of food, in the content of sugar and carbohydrates in the food they consume. Excess sugar consumption; obesity; and, conversely, the issue of a healthy lifestyle and the growing interest in healthy “alternative” lifestyles, have often been a subject of debate. The research has shown, among other things, that 58% of respondents consume sugar; 70% of men and 88% of women shop at health food stores at least occasionally; and the most monitored values are calories, carbohydrates, and sugar.

Medication and Supplement Use in Disability Football World Championships

BACKGROUND

Individuals with an impairment comprise more than 15% of the world's population, many of whom can benefit greatly from participation in sport. The provision of medical services in disability sport is a challenging area with a lack of scientific evidence. Given the positive impact that sport can have on the people with an impairment, it is vital that measures are taken to better understand the medical issues posed by disability sport. It is well established that medications and supplements are overused in sport, particularly within professional football, but there is no current evidence on medication or supplement use in elite disability football.

OBJECTIVE

To examine and describe the use of medication and supplements in disability football, before and during international tournaments, and to identify the profile of substances used by category.

DESIGN

Prospective, descriptive, cohort study.

SETTING

International Blind Sport Association Football World Cup 2015 and the International Federation of Cerebral Palsy Football World Cup 2015.

PARTICIPANTS

Two hundred forty-two elite-level disability footballers, classified with B1 visual impairment or cerebral palsy.

METHODS

Team clinicians were asked to document all medication and supplements taken in the 48 hours before each match.

RESULTS

This study recorded the use of 1648 substances in 242 players, with more than one half (53.1%) classified as supplements. There was an overall rate of 1.26 substances used per player per match and a medication use rate of 0.59 medications per player per match. Seventy percent (170/242) of players reported using at least one substance per tournament, with 57.9% (140/242) using at least one prescribed medication (63.6% of players at International Blind Sports Association World Games and 57.7% of players at International Federation of Cerebral Palsy World Cup). The most commonly prescribed category of medications was nonsteroidal anti-inflammatory drugs, representing 39.3% of all reported medications.

CONCLUSION

This study highlights the potential overuse of medication and supplements in disability football, particularly in the use of nonsteroidal anti-inflammatory drugs. These trends are comparable to previous research in Fédération Internationale de Football Association World Cup competitions.

LEVEL OF EVIDENCE

Not applicable.

CONSUMO DE PROTEÍNA DO SORO DO LEITE ENTRE ESTUDANTES UNIVERSITÁRIOS DE PORTO ALEGRE, RS

RESUMO Introdução: A proteína do soro do leite é uma das proteínas de maior valor biológico, por seu alto teor de aminoácidos. Em vista disso, a população tem consumo elevado do suplemento alimentar Whey Protein e esse uso exacerbado torna-se preocupante. Objetivo: Avaliar o perfil do consumo de Whey Protein (WP) bem como verificar como é utilizado, quais os tipos consumidos e se esse consumo está associado à prática de atividade física, além de se há alguma recomendação profissional. Métodos: A população analisada foi de alunos da Universidade Federal do Rio Grande do Sul, em Porto Alegre, matriculados nos cursos de graduação das áreas Biológicas, Naturais e Agrárias. As áreas contempladas foram selecionadas mediante sorteio e no total foram 11 cursos pertencentes a essas áreas que aceitaram participar do estudo. O instrumento de pesquisa utilizado para o objetivo proposto foi um questionário composto de 15 questões, sendo quatro questões de múltipla escolha. Resultados: Participaram do estudo 133 indivíduos com idade entre 18 e 28 anos (58,6% homens e 41,3% mulheres). Com relação à renda, 71,4% dos participantes ganham em média até três salários mínimos. O principal motivo do consumo de proteína do soro do leite foi a hipertrofia muscular (83,5%). O uso do suplemento Whey Protein foi indicado, em 62,4% dos casos, por amigos, vendedores ou por iniciativa própria. Conclusão: Fica evidente neste estudo, que a busca de melhor desempenho físico associado a padrões estéticos parece estar impulsionando o uso de Whey Protein, contudo, é preciso também conhecer o risco do uso exacerbado, principalmente quando não há acompanhamento de profissional qualificado nem há recomendações sobre quantidade, tipo e fracionamento do suplemento.

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.

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 systematic review and meta-analysis on the prevalence of dietary supplement use by military personnel

Background

Although a number of studies have been conducted on the prevalence of dietary supplement (DS) use in military personnel, these investigations have not been previously summarized. This article provides a systematic literature review of this topic.

Methods

Literature databases, reference lists, and other sources were searched to find studies that quantitatively examined the prevalence of DS use in uniformed military groups. Prevalence data were summarized by gender and military service. Where there were at least two investigations, meta-analysis was performed using a random model and homogeneity of the prevalence values was assessed.

Results

The prevalence of any DS use for Army, Navy, Air Force, and Marine Corps men was 55%, 60%, 60%, and 61%, respectively; for women corresponding values were 65%, 71%, 76%, and 71%, respectively. Prevalence of multivitamin and/or multimineral (MVM) use for Army, Navy, Air Force, and Marine Corps men was 32%, 46%, 47%, and 41%, respectively; for women corresponding values were 40%, 55%, 63%, and 53%, respectively. Use prevalence of any individual vitamin or mineral supplement for Army, Navy, Air Force, and Marine Corps men was 18%, 27%, 25%, and 24%, respectively; for women corresponding values were 29%, 36%, 40%, and 33%, respectively. Men in elite military groups (Navy Special Operations, Army Rangers, and Army Special Forces) had a use prevalence of 76% for any DS and 37% for MVM, although individual studies were not homogenous. Among Army men, Army women, and elite military men, use prevalence of Vitamin C was 15% for all three groups; for Vitamin E, use prevalence was 8%, 7%, and 9%, respectively; for sport drinks, use prevalence was 22%, 25% and 39%, respectively. Use prevalence of herbal supplements was generally low compared to vitamins, minerals, and sport drinks, ≤5% in most investigations.

Conclusions

Compared to men, military women had a higher use prevalence of any DS and MVM. Army men and women tended to use DSs and MVM less than other service members. Elite military men appeared to use DSs and sport drinks more than other service members.

Doing supplements to improve performance in club cycling: a life-course analysis

Using qualitative life-course and pathway analysis, this article explores the beliefs that serious club cyclists have about performance improvement, and what they think are appropriate and inappropriate ways of achieving it. We interviewed 11 cyclists from suburban clubs in Melbourne, Australia, and invited them to discuss their approach to training, racing, and supplementation. We found that each of the 11 cyclists were not only committed to the sport, but also paid a keen interest in bike technology and training regimes. In addition, they believed that supplement use was integral to meeting the physical and mental demands of their sport, even at club level. They also understood that supplement use, like training regimes, followed a sequential pathway where the accumulation of capacity, know-know, and knowledge, allowed progression to the next level of performance. And, like similar studies of club cycling in Europe, this cohort of cyclists balked at using banned substances, but also believed that in order to effectively transition to the elite - that is, professional - level, some additional supplement and drug-use was essential.

Unique aspects of competitive weightlifting: performance, training and physiology

Weightlifting is a dynamic strength and power sport in which two, multijoint, whole-body lifts are performed in competition; the snatch and clean and jerk. During the performance of these lifts, weightlifters have achieved some of the highest absolute and relative peak power outputs reported in the literature. The training structure of competitive weightlifters is characterized by the frequent use of high-intensity resistance exercise movements. Varied coaching and training philosophies currently exist around the world and further research is required to substantiate the best type of training programme for male and female weightlifters of various age groups. As competitive weightlifting is contested over eight male and seven female body weight categories, the anthropometric characteristics of the athletes widely ranges. The body compositions of weightlifters are similar to that of athletes of comparable body mass in other strength and power sports. However, the shorter height and limb lengths of weightlifters provide mechanical advantages when lifting heavy loads by reducing the mechanical torque and the vertical distance that the barbell must be displaced. Furthermore, the shorter body dimensions coincide with a greater mean skeletal muscle cross-sectional area that is advantageous to weightlifting performance. Weightlifting training induces a high metabolic cost. Although dietary records demonstrate that weightlifters typically meet their required daily energy intake, weightlifters have been shown to over consume protein and fat at the expense of adequate carbohydrate. The resulting macronutrient imbalance may not yield optimal performance gains. Cross-sectional data suggest that weightlifting training induces type IIX to IIA fibre-type transformation. Furthermore, weightlifters exhibit hypertrophy of type II fibres that is advantageous to weightlifting performance and maximal force production. As such, the isometric peak force and contractile rate of force development of weightlifters is ~15-20% and ~13-16% greater, respectively, than in other strength and power athletes. In addition, weightlifting training has been shown to reduce the typical sex-related difference in the expression of neuromuscular strength and power. However, this apparent sex-related difference appears to be augmented with increasing adult age demonstrating that women undergo a greater age-related decline in muscle shortening velocity and peak power when compared with men. Weightlifting training and competition has been shown to induce significant structural and functional adaptations of the cardiovascular system. The collective evidence shows that these adaptations are physiological as opposed to pathological. Finally, the acute exercise-induced testosterone, cortisol and growth hormone responses of weightlifters have similarities to that of following conventional strength and hypertrophy protocols involving large muscle mass exercises. The routine assessment of the basal testosterone : cortisol ratio may be beneficial when attempting to quantify the adaptive responses to weightlifting training. As competitive weightlifting is becoming increasingly popular around the world, further research addressing the physiological responses and adaptations of female weightlifters and younger (i.e. ≤17 years of age) and older (i.e. ≥35 years of age) weightlifters of both sexes is required.

Dietary supplementation and doping-related factors in high-level sailing

Background

Although dietary supplements (DSs) in sports are considered a natural need resulting from athletes’ increased physical demands, and although they are often consumed by athletes, data on DS usage in Olympic sailing are scarce. The aim of this study was to study the use of and attitudes towards DSs and doping problems in high-level competitive sailing.

Methods

The sample consisted of 44 high-level sailing athletes (5 of whom were female; total mean age 24.13 ± 6.67 years) and 34 coaches (1 of whom was female; total mean age 37.01 ± 11.70). An extensive, self-administered questionnaire of substance use was used, and the subjects were asked about sociodemographic data, sport-related factors, DS-related factors (i.e., usage of and knowledge about DSs, sources of information), and doping-related factors. The Kruskal-Wallis ANOVA was used to determine the differences in group characteristics, and Spearman’s rank order correlation and a logistic regression analysis were used to define the relationships between the studied variables.

Results

DS usage is relatively high. More than 77% of athletes consume DSs, and 38% do so on a regular basis (daily). The athletes place a high degree of trust in their coaches and/or physicians regarding DSs and doping. The most important reason for not consuming DSs is the opinion that DSs are useless and a lack of knowledge about DSs. The likelihood of doping is low, and one-third of the subjects believe that doping occurs in sailing (no significant differences between athletes and coaches). The logistic regression found crew number (i.e., single vs. double crew) to be the single significant predictor of DS usage, with a higher probability of DS consumption among single crews.

Conclusion

Because of the high consumption of DSs future investigations should focus on real nutritional needs in sailing sport. Also, since athletes reported that their coaches are the primary source of information about nutrition and DSs, further studies are necessary to determine the knowledge about nutrition, DSs and doping problems among athletes and their support teams (i.e., coaches, physicians, and strength and conditioning specialists).

Nutritional supplements: prevalence of use and contamination with doping agents

Based upon recent sales numbers, nutritional supplements play a key role in the lifestyle of a substantial proportion of the population. As well as products such as vitamins or minerals, several precursors of anabolic steroids are marketed as nutritional supplements. Another group of commercially available supplements are products for weight loss based upon herbal formulations originating from Ephedra species. Apart from supplements indicating the presence of these active compounds, numerous non-hormonal nutritional supplements were found that were contaminated with non-labelled anabolic steroids. Stimulating agents other than naturally occurring analogues of ephedrine were detected. A major group using dietary supplements are sportsmen, ranging from amateur level to elite athletes. Besides the possible health risks associated with the use of dietary supplements, athletes should take care not to violate the rules of the World Anti-Doping Agency because athletes remain responsible for substances detected in their biofluids, irrespective of their origin. Several analytical methods have been developed to determine the presence of doping agents as contaminants. The present review attempts to address the issues concerning the use of nutritional supplements and the detection of doping agents as contaminants in dietary supplements.

Unique aspects of competitive weightlifting: performance, training and physiology

Weightlifting is a dynamic strength and power sport in which two, multijoint, whole-body lifts are performed in competition; the snatch and clean and jerk. During the performance of these lifts, weightlifters have achieved some of the highest absolute and relative peak power outputs reported in the literature. The training structure of competitive weightlifters is characterized by the frequent use of high-intensity resistance exercise movements. Varied coaching and training philosophies currently exist around the world and further research is required to substantiate the best type of training programme for male and female weightlifters of various age groups. As competitive weightlifting is contested over eight male and seven female body weight categories, the anthropometric characteristics of the athletes widely ranges. The body compositions of weightlifters are similar to that of athletes of comparable body mass in other strength and power sports. However, the shorter height and limb lengths of weightlifters provide mechanical advantages when lifting heavy loads by reducing the mechanical torque and the vertical distance that the barbell must be displaced. Furthermore, the shorter body dimensions coincide with a greater mean skeletal muscle cross-sectional area that is advantageous to weightlifting performance. Weightlifting training induces a high metabolic cost. Although dietary records demonstrate that weightlifters typically meet their required daily energy intake, weightlifters have been shown to over consume protein and fat at the expense of adequate carbohydrate. The resulting macronutrient imbalance may not yield optimal performance gains. Cross-sectional data suggest that weightlifting training induces type IIX to IIA fibre-type transformation. Furthermore, weightlifters exhibit hypertrophy of type II fibres that is advantageous to weightlifting performance and maximal force production. As such, the isometric peak force and contractile rate of force development of weightlifters is ~15-20% and ~13-16% greater, respectively, than in other strength and power athletes. In addition, weightlifting training has been shown to reduce the typical sex-related difference in the expression of neuromuscular strength and power. However, this apparent sex-related difference appears to be augmented with increasing adult age demonstrating that women undergo a greater age-related decline in muscle shortening velocity and peak power when compared with men. Weightlifting training and competition has been shown to induce significant structural and functional adaptations of the cardiovascular system. The collective evidence shows that these adaptations are physiological as opposed to pathological. Finally, the acute exercise-induced testosterone, cortisol and growth hormone responses of weightlifters have similarities to that of following conventional strength and hypertrophy protocols involving large muscle mass exercises. The routine assessment of the basal testosterone : cortisol ratio may be beneficial when attempting to quantify the adaptive responses to weightlifting training. As competitive weightlifting is becoming increasingly popular around the world, further research addressing the physiological responses and adaptations of female weightlifters and younger (i.e. ≤17 years of age) and older (i.e. ≥35 years of age) weightlifters of both sexes is required.

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.

Nutrition guidelines for strength sports: sprinting, weightlifting, throwing events, and bodybuilding

Strength and power athletes are primarily interested in enhancing power relative to body weight and thus almost all undertake some form of resistance training. While athletes may periodically attempt to promote skeletal muscle hypertrophy, key nutritional issues are broader than those pertinent to hypertrophy and include an appreciation of the sports supplement industry, the strategic timing of nutrient intake to maximize fuelling and recovery objectives, plus achievement of pre-competition body mass requirements. Total energy and macronutrient intakes of strength-power athletes are generally high but intakes tend to be unremarkable when expressed relative to body mass. Greater insight into optimization of dietary intake to achieve nutrition-related goals would be achieved from assessment of nutrient distribution over the day, especially intake before, during, and after exercise. This information is not readily available on strength-power athletes and research is warranted. There is a general void of scientific investigation relating specifically to this unique group of athletes. Until this is resolved, sports nutrition recommendations for strength-power athletes should be directed at the individual athlete, focusing on their specific nutrition-related goals, with an emphasis on the nutritional support of training.

The Physiological Effects of Creatine Supplementation on Hydration: A Review

In 1992, Harris and colleagues demonstrated that oral creatine supplementation can enhance muscle creatine stores. Since then, creatine has become an important and popular ergogenic aid for improving athletic performance with reports of up to 74% of athletes supplementing with creatine. Although many recent studies have addressed the safety concerns of creatine supplementation on hydration status in hot and humid environments, anecdotal reports still exist linking creatine usage to heat-related problems. These concerns are based on the premise that creatine is an osmotically active substance resulting in an alteration in fluid balance by increasing intracellular fluid volume and preventing fluid from entering the extracellular environment to aid in thermoregulation. However, a number studies have demonstrated that when recommended amounts of creatine are consumed, creatine does not appear to increase the risk of heat-related problems during exercise and may actually have a positive influence on core temperature and heart rate responses.

Use of dietary supplements in Olympic athletes is decreasing: a follow-up study between 2002 and 2009

Background

The aim of this study was to assess the frequency of use of dietary supplements (DS) among large sample of elite Finnish athletes and to describe possible changes in dietary supplement use between the years 2002 and 2009.

Methods

A prospective follow-up study was conducted on Olympic athletes. The first survey was conducted on Olympic athletes in 2002 (N = 446) and the follow-up study was conducted between May 2008 and June 2009 (N = 372).

Results

In 2002, a total of 81% of the athletes used dietary supplements (a mean of 3.37 ± 3.06 DS per user) and in 2009, a total of 73% of the athletes (a mean of 2.60 ± 2.69 per DS user) used them. After adjusting for age-, sex- and sport type, the OR (95% confidence interval, CI) for use of any dietary supplement was significantly less in 2009 as compared with 2002 results (OR, 0.62; 95% CI, 0.43-0.90). Decrease in DS use was observed in all supplement subgroups (vitamins, minerals, nutritional supplements). Athletes in speed and power events and endurance events reported use of any dietary supplement significantly more often than team sport athletes both in 2002 and 2009. In year 2009, the frequency of all dietary supplement use increased when athlete's age increased and the increase was significant in older age groups: of the athletes under 21 years 63%, 21-24 years 83% and over 24 years 90% consumed nutritional supplements.

Conclusions

Based in our study, there seems to be a lowering trend of dietary supplement use among elite Finnish athletes although differences between sport subgroups and age groups are considerable.

Consumo de suplementos por jovens freqüentadores de academias de ginástica em São Paulo

A preocupação com a aparência e a estética pode levar ao consumo indiscriminado de suplementos nas academias. Os fatores relacionados ao consumo de suplementos em 201 jovens entre 15 e 25 anos freqüentadores de academias de ginástica da cidade de São Paulo foram investigados através da aplicação de formulário próprio. O uso de suplementos é relatado por 61,2% (n = 123) da amostra. Os homens usam mais suplementos que as mulheres (p < 0,001) e os adolescentes tendem a utilizar mais que os adultos jovens (p = 0,07). Os suplementos mais utilizados são bebidas esportiva (12%), hipercalóricos (12%), aminoácidos (10%), proteínas (10%) e creatina (8%), basicamente por auto-prescrição (42,8%) e pela indicação de treinadores (27,5%). O consumo de suplementos é significativamente maior entre aqueles que se exercitam há mais tempo; freqüentam a academia há mais tempo; e ficam na academia mais horas/semana. Ter amigos usuários (p = 0,03) e/ou um usuário em casa (p = 0,01) influencia no consumo de suplementos. O consumo de suplementos é uma prática que faz parte da realidade das academias de ginástica e o ambiente é favorecedor do uso desses produtos.

The age-gender-status profile of high performing athletes in the UK taking nutritional supplements: lessons for the future

Background

Owing to the mechanics of anti-doping regulation via the World Anti-Doping Agency's Prohibited List, nutritional supplement use received little attention in comparison to the prevalence of doping. The aims of this study were to investigate supplement use, identify groups of athletes with high levels of supplement use and the prevalence of concomitant use of supplements.

Methods

Survey data from 847 high-performing athletes in the UK were analysed using descriptive statistics. The survey, conducted by UK Sport, consisted of questions regarding knowledge of the prohibited substances, testing procedure, nutritional supplement use and perceptions of the doping problem. The proportion of supplement users and the relative use of each supplement were compared by age, gender and professional status.

Results

Among 874 high-performing athletes in the UK sample, 58.8% of them reported the use of at least one nutritional supplement. Among supplement users, 82.6% used more than one and 11.5% reported use of more than five nutritional supplements. Of the 9 supplements listed, multivitamins (72.6%) and vitamin C (70.7%) were used most, followed by creatine (36.1%), whey protein (31.7%), echinacea (30.9%), iron (29.9%) and caffeine (23.7%). Less than 11% reported the use of magnesium or ginseng. Creatine use was typically associated with males regardless of status and across all ages, whereas iron was characteristically used by females. A 'typical' supplement user is male, between 24 and 29 years of age, involved in professional sport and using a combination of supplements. Male professional players between age 30 and 34 years, and female non-professional athletes between 24 and 29 years of age also represented a considerable proportion of supplement users. Athletes older than 40 years of age were practically non-users. Concomitant use of supplements is characteristic of male users more than females.

Conclusion

As supplement use has been previously shown to increase the probability of prohibited substance use, groups exhibiting high use of nutritional supplements should be monitored. Future research should incorporate a wide range of supplements and enquire about the daily amount ingested. In addition to tutoring, preventive measures should incorporate offering acceptable and healthy alternatives for assisted performance enhancement.

Nutritional ergogenic aids and exercise performance

The use of nutritional supplements in sport is widespread and few serious athletes do not, at some stage in their career, succumb to the temptation to experiment with one or more nutritional supplements. Nutritional ergogenic aids are aimed primarily at enhancing performance (either by affecting energy metabolism or by an effect on the central nervous system), at increasing lean body mass or muscle mass by stimulation of protein synthesis and at reducing body fat content. Although not strictly ergogenic (i.e. capable of enhancing work performance), supplements aimed at increasing resistance to infection and improving general health are seen by athletes as important in reducing the interruptions to training that minor illness and infection can cause. Creatine is perhaps the most widely used supplement in sport at the moment. Supplementation can increase muscle creatine phosphate levels and, although not all published studies show positive results, there is much evidence that performance of short-term high-intensity exercise can be improved by supplementation. Ingestion of large doses of bicarbonate can enhance performance of exercise where metabolic acidosis may be a limiting factor, but there is a significant risk of adverse gastrointestinal side effects. Caffeine can also improve performance, in part by a stimulation of fatty acid mobilization and sparing of the body's limited carbohydrate stores, but also via direct effects on muscle and possibly by central nervous system effects on the perception of effort and fatigue. Carnitine plays an essential role in fatty acid oxidation in muscle but, although supplements are used by athletes, there is no good evidence of a beneficial effect of supplementation. None of these products contravenes the International Olympic Committee regulations on doping in sports, although caffeine is not permitted above a urine concentration of 12 mg/l. Supplementation is particularly prevalent among strength and power athletes, where an increase in muscle mass can benefit performance. Protein supplements have not been shown to be effective except in those rare cases where the dietary protein intake is otherwise inadequate. Individual amino acids, especially ornithine, arginine and glutamine, are also commonly used, but their benefit is not supported by documented evidence. Cr and hydroxymethylbutyrate are also used by strength athletes, but again there are no well-controlled studies to provide evidence of a beneficial effect. Athletes use a wide variety of supplements aimed at improving or maintaining general health and vitamin and mineral supplementation is widespread. There is a theoretical basis, and limited evidence, to support the use of antioxidant vitamins and glutamine during periods of intensive training, but further evidence is required before the use of these supplements can be recommended.

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.

Supplement use in sport: is there a potentially dangerous incongruence between rationale and practice?

BACKGROUND

Supplement use by athletes is complex and research supports the alarming notion of misinformed decisions regarding supplements.

HYPOTHESIS

A frequent divergence between the type of supplements chosen by athletes and the rationale dictating the supplement use is hypothesized. Thus, a potentially dangerous incongruence may exist between rationale and practice.

TESTING THE HYPOTHESIS

In the continued absence of reliable data on supplement use, an alternative approach of studying the reasons underlying supplement use in athletes is proposed to determine whether there is an incongruence between rationale and practice. Existing data from large scale national surveys can be used to investigate this incongruence.

IMPLICATIONS OF THE HYPOTHESIS

In this report, analyses of distinctive patterns between the use and rationale for use of supplements among athletes are recommended to explore this potentially dangerous phenomenon.

Uso referido de medicamentos e suplementos alimentares nos atletas selecionados para controle de doping nos Jogos Sul-Americanos

O objetivo do presente estudo foi descrever a prevalência do uso de medicamentos e suplementos alimentares em atletas que participaram dos controles obrigatórios de dopagem dos VII Jogos Desportivos Sul-Americanos, realizados em quatro cidades brasileiras, analisando estatisticamente um quesito proposto no controle de dopagem e relativo às substâncias utilizadas nos dias que antecederam a competição. Foram analisados dados coletados em 234 atletas de 25 esportes dos Jogos, 136 do sexo masculino e 98 do feminino, distribuídos entre os 13 países participantes. Constatou-se que no controle de doping, 44% dos atletas informaram a utilização de medicamentos até três dias antes da competição. Estes medicamentos foram classificados em antiinflamatórios não esteróides (AINEs) (24,8%), analgésicos (15,9%), antibióticos (4,3%), antigripais (3%) e outros medicamentos (19,3%). Relataram o uso de suplementos alimentares 50% de atletas da amostra estudada, sendo este grupo dividido em vitaminas (39,7%), sais minerais (21,9%), aminoácidos (18,9%) e outras substâncias (13,3%). Os autores concluem que há um uso exagerado de antiinflamatórios e analgésicos em várias modalidades desportivas, o que causa preocupação em termos de controle de sintomatologia dos atletas em competição, além de uso excessivo de suplementos alimentares, para os quais não existe indicação específica, e que podem ocasionar um eventual resultado analítico adverso no controle de doping por contaminação ou manipulação.

Influence of performance level on dietary supplementation in elite Canadian athletes

INTRODUCTION

It is well documented that athletes report greater dietary supplement (DS) usage than nonathletes; however, limited data exist for Canadian athletes, especially relative to competitive performance levels.

PURPOSE

This descriptive and analytical, cross-sectional research investigated DS practices and opinions, preferred means for DS education, and antidoping opinions among elite Canadian athletes competing at various performance levels.

METHODS

Subjects completed a validated questionnaire by recall. Combined, 582 high-performance athletes (314 M, 268 F) between the ages of 11 and 42 yr (mean 19.96 +/- 3.91 yr) and representing 27 sports activities participated. Respondents were categorized into five competitive performance levels: provincial (68), national (101), North America (61), international or professional (89), and varsity (263).

RESULTS

Overall, most (88.4%) reported taking one or more DS during the previous 6 months (mean 3.08 +/- 1.87 DS per user). From a total of 1555 DS declared, 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. Athletes at the highest performance level were significantly more likely to use protein supplements, to be advised by strength trainers regarding DS usage, to have a higher self-rating of their diet, to prefer individual interviews for DS educational purposes, to perceive greater awareness of antidoping legislation, and train more h.wk(-1). Furthermore, differences were observed for the types of DS reported and justifications for use.

CONCLUSION

This dataset, the first of its kind in Canada, was generated with a validated and reliable questionnaire and has the potential to be extended nationally and internationally to provide greater insight into the patterns and opinions of elite athletes regarding supplementation and antidoping.

Contamination of dietary supplements and positive drug tests in sport

The use of dietary supplements is widespread in sport and most athletes competing at the highest level of competition use some form of dietary supplementation. Many of these supplements confer no performance or health benefit, and some may actually be detrimental to both performance and health when taken in high doses for prolonged periods. Some supplements contain excessive doses of potentially toxic ingredients, while others do not contain significant amounts of the ingredients listed on the label. There is also now evidence that some of the apparently legitimate dietary supplements on sale contain ingredients that are not declared on the label but that are prohibited by the doping regulations of the International Olympic Committee and of the World Anti-Doping Agency. Contaminants that have been identified include a variety of anabolic androgenic steroids (including testosterone and nandrolone as well as the pro-hormones of these compounds), ephedrine and caffeine. This contamination may in most cases be the result of poor manufacturing practice, but there is some evidence of deliberate adulteration of products. The principle of strict liability that applies in sport means that innocent ingestion of prohibited substances is not an acceptable excuse, and athletes testing positive are liable to penalties. Although it is undoubtedly the case that some athletes are guilty of deliberate cheating, some positive tests are likely to be the result of inadvertent ingestion of prohibited substances present in otherwise innocuous dietary supplements.

Potential ergogenic effects of arginine and creatine supplementation

The rationale for the use of nutritional supplements to enhance exercise capacity is based on the assumption that they will confer an ergogenic effect above and beyond that afforded by regular food ingestion alone. The proposed or advertised ergogenic effect of many supplements is based on a presumptive metabolic pathway and may not necessarily translate to quantifiable changes in a variable as broadly defined as exercise performance. L-arginine is a conditionally essential amino acid that has received considerable attention due to potential effects on growth hormone secretion and nitric oxide production. In some clinical circumstances (e.g., burn injury, sepsis) in which the demand for arginine cannot be fully met by de novo synthesis and normal dietary intake, exogenous arginine has been shown to facilitate the maintenance of lean body mass and functional capacity. However, the evidence that supplemental arginine may also confer an ergogenic effect in normal healthy individuals is less compelling. In contrast to arginine, numerous studies have reported that supplementation with the arginine metabolite creatine facilitates an increase in anaerobic work capacity and muscle mass when accompanied by resistance training programs in both normal and patient populations. Whereas improvement in the rate of phosphocreatine resynthesis is largely responsible for improvements in acute work capacity, the direct effect of creatine supplementation on skeletal muscle protein synthesis is less clear. The purpose of this review is to summarize the role of arginine and its metabolite creatine in the context of a nutrition supplement for use in conjunction with an exercise stimulus in both healthy and patient populations.

Dietary supplements

For the athlete training hard, nutritional supplements are often seen as promoting adaptations to training, allowing more consistent and intensive training by promoting recovery between training sessions, reducing interruptions to training because of illness or injury, and enhancing competitive performance. Surveys show that the prevalence of supplement use is widespread among sportsmen and women, but the use of few of these products is supported by a sound research base and some may even be harmful to the athlete. Special sports foods, including energy bars and sports drinks, have a real role to play, and some protein supplements and meal replacements may also be useful in some circumstances. Where there is a demonstrated deficiency of an essential nutrient, an increased intake from food or from supplementation may help, but many athletes ignore the need for caution in supplement use and take supplements in doses that are not necessary or may even be harmful. Some supplements do offer the prospect of improved performance; these include creatine, caffeine, bicarbonate and, perhaps, a very few others. There is no evidence that prohormones such as androstenedione are effective in enhancing muscle mass or strength, and these prohormones may result in negative health consequences, as well as positive drug tests. Contamination of supplements that may cause an athlete to fail a doping test is widespread.

Nutritional supplements in Norwegian elite athletes--impact of international ranking and advisors

The aims of this study were to investigate (a) the use of nutritional supplements (NS) (vitamins, minerals, Omega 3, antioxidants, ginseng, amino acids, Creatine and energy supplements) in elite athletes of different international ranking (b) why athletes are using NS, and (c) who recommends the elite athletes to use NS. The total population of elite athletes in Norwegian National Teams (n = 1620, 960 males and 660 females aged 15-39 years) and randomly selected (n = 1681) (916 males and 765 females) controls from the general population, were given a questionnaire including questions about use of nutritional supplements (NS), and from whom athletes had received information about nutrition and recommendations to use NS. The response rate was 76% for male and 92% for female athletes and 75% and 81% for male and female controls, respectively. A similar percentage of female athletes (54%) and controls (52%) reported use of one or more NS, but more male athletes (51%) than male controls (32%) used NS (P < 0.001). However, independent of gender, more athletes as compared to controls used minerals (males 26% vs. 8%; females 42% vs. 20%), amino acids (males 12% vs. 4%; females 3% vs. 0), and Creatine (males 12% vs. 2%; females 3% vs. 0). A lower percentage of NS users were observed in the best female athletes (52%) as compared to female athletes with less experience of international competition (73%) (P < 0.01). In male athletes, NS use was independent of international ranking (49%-53%). The coach was the main advisor for use of NS for both male (58%) and female athletes (52%). For male and female athletes, the main reason for using NS was that they felt it was needed in addition to their daily intake (56% and 67%, respectively). Forty one percent of the male and 37% of the female athletes using NS felt they were well informed about nutrition in general and NS. However, 8% of the NS users did not know whether the NS they used was doping classified or not.

IN CONCLUSION

we found that a similar percentage of female elite athletes and controls, but a higher percentage of male elite athletes than controls, reported the use of NS. There was a lower percentage of NS use among the top female athletes, but not the top male athletes as compared to the less successful elite athletes. The coach was the main advisor for NS use both for male and female elite athletes.

A high exercise load is linked to pathological weight control behavior and eating disorders in female fitness instructors

Demographic data, exercise habits, weight control behavior, attitudes towards body shape, eating disorder (ED) experience, and menstrual regularity among female fitness instructors were descriptively assessed. A 60-item questionnaire was sent to 295 female fitness instructors at eight fitness centers. Responders (57%) reported a mean weekly exercise load of 5.5 h week(-1) (SD 2.6), which indicates frequent training, however, less than that of athletes. Overall, 35% reported ED experience (DSM-IV criteria), with an onset at 15-17 years of age. The problems had lasted 5-7 years, and 20% of the entire group reported recovery, however, 11% still had EDs. For the entire group, it was found that a high weekly exercise load was linked to a pathological weight control behavior. Fitness instructors with an active ED exercised more than instructors who never had an ED or who had a past ED. Menstrual irregularity was more common among instructors who did not use contraceptives (14%), compared to those who did (5%). As ED experience and pathological weight control behavior were common in the studied group, the importance of guidelines regarding communication from female fitness instructors about healthy training habits to regular exercisers is discussed in the article.

The athlete's diet: nutritional goals and dietary strategies

When talented, motivated and highly trained athletes meet for competition the margin between victory and defeat is usually small. When everything else is equal, nutrition can make the difference between winning and losing. Although the primary concern of many athletes is to supplement the diet with protein, vitamins and minerals, and a range of more exotic compounds, key dietary issues are often neglected. Athletes must establish their nutritional goals, and must also be able to translate them into dietary strategies that will meet these goals. Athletes are often concerned with dietary manipulations in the period around competition, but the main role of nutrition may be to support consistent intensive training which will lead to improved performance. Meeting energy demand and maintaining body mass and body fat at appropriate levels are key goals. An adequate intake of carbohydrate is crucial for maintaining muscle glycogen stores during hard training, but the types of food and the timing of intake are also important. Protein ingestion may stimulate muscle protein synthesis in the post-exercise period, promoting the process of adaptation in the muscles. Restoration of fluid and electrolyte balance after exercise is essential. If energy intake is high and a varied diet is consumed, supplementation of the diet with vitamins and minerals is not warranted, unless a specific deficiency is identified. Specific strategies before competition may be necessary, but this requirement depends on the demands of the sport. Generally, it is important to ensure high pre-competition glycogen stores and to maintain fluid balance. There is limited evidence to support the use of dietary supplements, but some, including perhaps creatine and caffeine, may be beneficial.

Minerals, trace elements and related biological variables in athletes and during physical activity

This review concerns various minerals (sodium, potassium, calcium, magnesium, phosphorus), trace elements (zinc, manganese, selenium, copper, iron, cobalt, iodine, chromium, fluorine, lead, cadmium) and other biological variables (nitric oxide, L-carnitine, glutamine, serum transferrin receptor, biopyrrins) in relation to hemorheologic effects, stress, immune response and infections during physical and sports activities. In athletes, macroelements in the ionized form contribute to heart and muscle contractions, oxidative phosphorylation and the synthesis and activation of enzymatic systems. Zinc (Zn) protects against the effects of increased free reactive oxygen species such as copper (Cu) and manganese (Mn) (Cu-Zn superoxide dismutases; Mn superoxide dismutase). Selenium in glutathione peroxidase protects the cardiovascular system and the muscles, and helps combat allergic and inflammatory diseases. Copper and iron are involved in many aspects of energy metabolism and are important components in the synthesis of hemoglobin, myoglobin and cytochromes. Fluorine and Cu protect the ligaments and tendons. Physical activity appears to be beneficial to urban residents who are exposed to metal pollution (lead, cadmium). The data cited in this review are often contradictory and incomplete. It is still unclear in many cases how minerals are involved in physiological changes, and much work remains.

Creatine use among a select population of high school athletes

OBJECTIVE

To determine the prevalence, frequency, and patterns of creatine use among a local population of high school athletes.

SUBJECTS AND METHODS

Male and female high school athletes completed an anonymous questionnaire on creatine use during the August 1999 preparticipation examinations at a single institutional sports medicine center.

RESULTS

A total of 328 students (182 males and 146 females) aged 14 to 18 years (mean +/- SD 15.2 +/- 1.3 years) completed the survey (100% response rate), although not all athletes answered each question. Twenty-seven athletes (8.2% of total group), 1 of whom was female, reported creatine use. Of these 27 athletes, 14 (52%) were taking creatine at the time of the survey. The frequency of creatine use among past and current users was equally distributed among rarely (30%), weekly (35%), and daily (35%). Creatine users were older than nonusers (mean 16.5 +/- 1.2 vs 15.0 +/- 1.3 years; P < .001). Of creatine users, 21 (78%) were male football players. Nineteen of 24 respondents (79%) believed creatine improved their performance. Overall, 78% of users either did not know how much creatine they were taking (12/22 respondents) or were taking greater than the recommended doses (5/22 respondents). Minor gastrointestinal side effects or muscle cramps were reported by 5 (20%) of 25 respondents. Creatine users were more likely than nonusers to know other creatine users (81% vs 22%; P < .001) and to use other supplements (67% vs 9%; P < .001). Creatine users obtained creatine information primarily from friends (74%) and purchased creatine predominantly from health food stores (86%).

CONCLUSIONS

High school male and female athletes as young as 14 years use creatine. Of high school athletes participating in our study, 8.2% reported creatine use. Relatively minor side effects, diarrhea, cramps, and loss of appetite, were reported. Creatine users seem to believe that creatine improves their performance, but they may lack sufficient information to make informed decisions regarding creatine use. Further larger scale study is warranted.