Intercollegiate student athlete use of nutritional supplements and the role of athletic trainers and dietitians in nutrition counseling

Does Nutrition Knowledge and Practice of Athletes Translate to Enhanced Athletic Performance? Cross-Sectional Study Amongst Nigerian Undergraduate Athletes

INTRODUCTION & OBJECTIVES

Nutrition knowledge of an athlete, as well as practice, is expected to influence athlete's performance. The study assessed the nutrition knowledge and practice as well as athletes' performance and identified the factors predicting the athletes' performance.

METHODOLOGY

A cross-sectional survey, involved 110 purposively selected undergraduate athletes (47 females, 63 males) of University of Ibadan, Nigeria, between July 2013 and December 2013. A semi-structured, self-administered questionnaire assessed the nutrition knowledge and practice. 24-hr diet recall and food frequency questionnaire were done. Anthropometric measurements were taken; body composition was determined by bioelectrical impedance analysis method. Handgrip strength (HGS), as an indirect measure of athlete performance, was assessed with the hand dynamometer. Chi-square and t-test analysis were used for the bivariate analysis. Pearson correlation and simple linear regression were used to determine relationships and predict athletic performance. The level of statistical significance was p<0.05.

RESULTS

More than half (58.2%) had good nutrition knowledge (NK), and 62.7% had good nutrition practices (NP). Majority (75.4%) had normal handgrip strength (HGS). More than 70.0% frequently do not consume cereals, roots and tubers, fruits and vegetables, legumes /nuts. About 30.0-40.0% frequently do not consume eggs/milk, meat/fish. Having good NK was significantly associated with good NP (χ2=15.520, p=0.000), but not with athlete's performance (HGS). There is no significant correlation between NK, NP, and HGS. There is a significant positive correlation between HGS and lean muscle mass (LMM) (r=.670, p=0.000), weight (r=.492, p=0.000), height (r=.521, p=0.000) and energy intake (r=.386, p=0.000). There is a significant negative correlation between HGS and percentage body fat (r=-.400, p=0.000). Athletes' performance was significantly predicted by the resting metabolic rate (beta=.454 C.I=0.011 to 0.045, p=0.003), Lean muscle mass (beta=.297 C.I=.059 to 0.562, p=0.024) and the weight (beta=.228, C.I=1.852 to .489, p=0.047).

CONCLUSION

Having good nutrition knowledge or practice did not directly determine athletic performance. However, there is the need for nutrition education interventions, to improve athlete's performance by promoting adequate energy intake, lean muscle mass and appropriate weight gain in athletes.

Nutritional supplement and doping use in sport: Possible underlying social cognitive processes

There is growing evidence suggesting that nutritional supplement (NS) use is strongly associated to doping use in elite and amateur sports. However, there is a paucity of research on the psychological processes that underlie this association. The present study investigated the cognitive and behavioral components of the association between NS use and doping among adolescent sub-elite athletes. Six hundred and fifty adolescent athletes completed a questionnaire including measures of doping intentions, attitudes, norms, and beliefs about NS use. The results showed that NS users who did not report doping use had significantly stronger doping intentions and more positive attitudes and favorable beliefs toward doping use, as compared with athletes who did not use NS. In support of the "shared mental representations" hypothesis, the present findings show that NS use is associated with biased reasoning patterns in favor of doping use. This mechanism may explain why some NS users decide to engage in doping.

Nutritional knowledge of UK coaches

Athletes obtain nutritional information from their coaches, yet their competency in this area is lacking. Currently, no research exists in the UK which has a different coach education system to many other countries. Therefore, the aim of this study was to evaluate the sports nutrition knowledge of UK coaching certificate (UKCC) level 2 and 3, hockey and netball qualified coaches. All coaches (n = 163) completed a sports nutrition questionnaire to identify: (a) if they provided nutritional advice; (b) their level of sport nutrition knowledge; and (c) factors that may have contributed to their level of knowledge. Over half the coaches provided advice to their athletes (n = 93, 57.1%), even though they were not competent to do so. Coaches responded correctly to 60.3 ± 10.5% of all knowledge questions with no differences between those providing advice and those who did not (p > 0.05). Those coaches who had undertaken formal nutrition training achieved higher scores than those who had not (p < 0.05). In conclusion, UK sports coaches would benefit from continued professional development in sports nutrition to enhance their coaching practice.

National Athletic Trainers' Association position statement: evaluation of dietary supplements for performance nutrition

OBJECTIVES

To help athletic trainers promote a "food-first" philosophy to support health and performance, understand federal and sport governing body rules and regulations regarding dietary supplements and banned substances, and become familiar with reliable resources for evaluating the safety, purity, and efficacy of dietary supplements.

BACKGROUND

The dietary supplement industry is poorly regulated and takes in billions of dollars per year. Uneducated athletes need to gain a better understanding of the safety, eligibility, and efficacy concerns associated with choosing to take dietary supplements. The athletic trainer is a valuable athletic team member who can help in the educational process. In many cases, athletic trainers are asked to help evaluate the legality, safety, and efficacy of dietary supplements. For this position statement, our mission is to provide the athletic trainer with the necessary resources for these tasks.

RECOMMENDATIONS

Proper nutrition and changes in the athlete's habitual diet should be considered first when improved performance is the goal. Athletes need to understand the level of regulation (or lack thereof) governing the dietary supplement industry at the international, federal, state, and individual sport-participation levels. Athletes should not assume a product is safe simply because it is marketed over the counter. All products athletes are considering using should be evaluated for purity (ie, truth in labeling), safety, and efficacy.

Use of Dietary Supplements among Professional Athletes in Saudi Arabia

The objective of this study was to understand the usage patterns of dietary supplements among professional athletes in Saudi Arabia. The survey consisted of sixteen questions divided into four categories: use of supplements, reason for consumption of supplements, personal beliefs about supplements, and behavior. The questionnaires were given to the three teams residing in Riyadh: Al Hilal, Al Nasr, and Al-Shabab. Out of the 105 athletes surveyed, we found that only 98 are currently taking dietary supplements and the mean age and standard deviation were 25.74 ± 2.90. The survey results showed a high percentage of athletes (93.3%; n = 98) using different dietary supplements throughout the season, 43.8% (n = 43) reported using supplements for performance, and 32.6% (n = 32) believed in health benefits as a reason for using dietary supplements. Our results showed that a total of 87 (88.7%), 81 (82.6%), and 51 (52.0%) athletes are consuming sports drinks, vitamin C, and multivitamins, respectively. Meanwhile, those supplements ranking among the least used included omega 6 (18.6%), creatine (16.3%), and Ginkgo biloba (10.2%). A majority of athletes indicated that their use of supplements was for the purpose of improving their health and performance.

Sports nutrition knowledge among collegiate athletes, coaches, athletic trainers, and strength and conditioning specialists

CONTEXT

Coaches, athletic trainers (ATs), strength and conditioning specialists (SCSs), and registered dietitians are common nutrition resources for athletes, but coaches, ATs, and SCSs might offer only limited nutrition information. Little research exists about sports nutrition knowledge and current available resources for nutrition information for athletes, coaches, ATs, and SCSs.

OBJECTIVE

To identify resources of nutrition information that athletes, coaches, ATs, and SCSs use; to examine nutrition knowledge among athletes, coaches, ATs, and SCSs; and to determine confidence levels in the correctness of nutrition knowledge questions within all groups.

DESIGN

Cross-sectional study.

SETTING

National Collegiate Athletic Association Division I, II, and III institutions across the United States.

PATIENTS AND OTHER PARTICIPANTS

The 579 participants consisted of athletes (n = 185), coaches (n = 131), ATs (n = 192), and SCSs (n = 71).

MAIN OUTCOME MEASURE(S)

Participants answered questions about nutrition resources and domains regarding basic nutrition, supplements and performance, weight management, and hydration. Adequate sports nutrition knowledge was defined as an overall score of 75% in all domains (highest achievable score was 100%).

RESULTS

Participants averaged 68.5% in all domains. The ATs (77.8%) and SCSs (81.6%) had the highest average scores. Adequate knowledge was found in 35.9% of coaches, 71.4% of ATs, 83.1% of SCSs, and only 9% of athletes. The most used nutrition resources for coaches, ATs, and SCSs were registered dietitians.

CONCLUSIONS

Overall, we demonstrated that ATs and SCSs have adequate sports nutrition knowledge, whereas most coaches and athletes have inadequate knowledge. Athletes have frequent contact with ATs and SCSs; therefore, proper nutrition education among these staff members is critical. We suggest that proper nutrition programming should be provided for athletes, coaches, ATs, and SCSs. However, a separate nutrition program should be integrated for ATs and SCSs. This integrative approach is beneficial for the continuity of care, as both categories of professionals might be developing and integrating preventive or rehabilitative programs for athletes.

Personal food systems of male collegiate football players: a grounded theory investigation

CONTEXT

Factors that affect food choices include the physical and social environments, quality, quantity, perceived healthfulness, and convenience. The personal food choice process was defined as the procedures used by athletes for making food choices, including the weighing and balancing of activities of daily life, physical well-being, convenience, monetary resources, and social relationships.

OBJECTIVE

To develop a theoretical model explaining the personal food choice processes of collegiate football players.

DESIGN

Qualitative study.

SETTING

National Collegiate Athletic Association Division II football program.

PATIENTS OR OTHER PARTICIPANTS

Fifteen football players were purposefully sampled to represent various positions, years of athletic eligibility, and ethnic backgrounds.

DATA COLLECTION AND ANALYSIS

For text data collection, we used predetermined, open-ended questions. Data were analyzed using the constant comparison method. The athletes' words were used to label and describe their interactions and experiences with the food choice process. Member checks and an external audit were conducted by a qualitative methodologist and a nutrition specialist, and the findings were triangulated with the current literature to ensure trustworthiness of the text data.

RESULTS

Time was the core category and yielded a cyclic graphic of a theoretical model for the food choice system. Planning hydration, macronutrient strategies, snacks, and healthful food choices emerged as themes.

CONCLUSIONS

The athletes planned meals and snacks around their academic and athletic schedules while attempting to consume foods identified as healthful. Healthful foods were generally lower in fat but high in preferred macronutrients. High-protein foods were the players' primary goal; carbohydrate consumption was secondary. The athletes had established plans to maintain hydration. Professionals may use these findings to implement educational programs on food choices for football players.

Exploring the feasibility of an academic course that provides nutrition education to collegiate student-athletes

The purpose of this article is to explore the delivery of nutrition education to collegiate student-athletes through an academic course. Existing literature has established the need for nutrition education among collegiate athletes. This article considers the collaboration of the university and the athletic department to better serve this population. Academic wellness courses for student-athletes can be used as models. Finally, benefits, barriers, and proposed course objectives are considered. This report proposes a potential solution to provide consistent, sustainable nutrition education to collegiate student-athletes.

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.

Evaluation of the nutrition knowledge of sports department students of universities

BACKGROUND

Individuals who have knowledge on the importance of adequate and balanced diet and reflect this knowledge to their behaviors are considered to be more successful in sports life. The present study aims to evaluate the nutrition knowledge of students receiving sports education in universities.

METHODS

The study sample consists of 343 voluntary students from the Sports Departments of Hacettepe, Gazi and Ankara Universities in Ankara. The questionnaire used in the study included a demographic section, and 30 questions on true-false nutrition knowledge. For the reliability of the questionnaire, the internal consistency coefficient was calculated and the Kuder Richardson (KR-20) value was found to be 0.71. For higher reliability, 9 dysfunctional questions were excluded from the questionnaire. The research data were collected through a questionnaire form and face-to-face interviews. For the statistical analyses of the data, tables were prepared to show mean, standard deviation (X̄±SD) and percentage (%) values. In order to determine the nutrition knowledge of students, the "independent t test" was used for nutrition lesson and gender.

RESULTS

University students receiving sports education and expected to continue their professional lives on sport-related fields were determined to have the lack of knowledge on nutrition. The mean value about the nutrition knowledge of the first year students was found 11.150 ± 2.962, while the mean value of the fourth year students was 13.460 ± 3.703, and the difference is statistically significant (p = .000).

CONCLUSION

Students, coaches and teachers in physical education were found not to give the necessary importance to their diets, and they were still not aware of the importance of nutrition on performance.

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.

Effects of various sodium bicarbonate loading protocols on the time-dependent extracellular buffering profile

Although much research has investigated the types of exercise that are enhanced with sodium bicarbonate (NaHCO3) ingestion, to date, there has been limited research on the dosage and timing of ingestion that optimizes the associated ergogenic effects. This study investigated the effects of various NaHCO3 loading protocols on the time-dependent blood-buffering profile. Eight male volunteers (age, 22.4 +/- 5.7 yr; height, 179.8 +/- 9.6 cm, body mass, 76.3 +/- 14.1 kg) completed Part A, measures of alkalosis throughout 120 minutes after ingestion of various single NaHCO3 dosages (0.3 gxkg-1, 0.2 gxkg-1, 0.1 gxkg-1, and placebo); and Part B, similar profiles after alternative NaHCO3 loading protocols (single morning dosage [SMD], single evening dosage [SED], and dosages ingested on 3 consecutive evenings [CED]). Results from Part A are as follows. Blood buffering in the 0.1 gxkg-1 condition was significantly lower than the 0.2 g.kg-1 and 0.3 gxkg-1 conditions (p < 0.002), but there was no significant differences between the 0.2 gxkg -1and 0.3 g.kg-1 conditions (p = 0.34). Although the blood buffering was relatively constant in the 0.1 and 0.2 conditions, it was significantly higher at 60 minutes than at 100 minutes and 120 minutes in the 0.3 gxkg-1 condition (p < 0.05). Results from Part B are as follows. Blood buffering for SMD was significantly higher than for SED and CED (p < 0.05). Blood buffering in the SMD condition was significantly lower at 17:00 hours than at 11:00 hours (p = 0.007). The single 0.2 and 0.3 gxkg-1 NaHCO3 dosages appeared to be the most effective for increasing blood-buffering capacity. The 0.2 gxkg-1 dosage is best ingested 40 to 50 minutes before exercise and the 0.3 gxkg-1 dosage 60 minutes before exercise.

Predicting future anabolic-androgenic steroid use intentions with current substance use: findings from an internet-based survey

OBJECTIVE

To explore how current substance use, including the use of sports supplements and illicit drugs, may impact upon a person's future intentions to use anabolic-androgenic steroids (AAS).

DESIGN

Web-based survey.

PARTICIPANTS

Two hundred fourteen exercising males (mean age, 30 years; range, 17-61 years) recruited from 5 gymnasia in Sydney, Australia, completed a web-based survey. The survey contained questions relating to sport supplement use, illicit substance use, reasons for currently not using AAS, and reasons for intending to use AAS in the future.

INTERVENTIONS

Participants completed a structured interview schedule that included questions regarding licit and illicit substance use, reasons for non-AAS use, and, where appropriate, reasons for intended future AAS use.

MAIN OUTCOME MEASURES

The planned main outcome measure was positive intention to use AAS.

RESULTS

Sixteen percent of the sample indicated that they would use AAS in the future. Reasons for future AAS use included increasing muscle size (80%), improving appearance (74%), and increasing strength (57%). Four-fifths (80%) of the sample reported use of sports supplements, with vitamins and protein supplements commonly reported (83% and 67%, respectively); more than one-third (36%) reported use of creatine in the past 6 months. Half (52%) of the sample reported use of illicit substances in the preceding 6 months, with amphetamines and cannabis commonly reported (66% and 62%, respectively). Significant predictors of intending to use AAS included past 6-month use of creatine and knowing AAS users.

CONCLUSIONS

The use of sport supplements and/or illicit substances may remove barriers for the future use of such drugs as AAS. Future research is necessary to explore in depth whether such substances may act as a "gateway" to future AAS use.

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.

Towards an empirical model of performance enhancing supplement use: a pilot study among high performance UK athletes

This paper addressed a gap in the literature of empirically derived models of performance enhancing supplement use by developing a demographic and psychosocially based model of athlete supplement use. Selected questions were used from a larger survey conducted by UK Sport into British athletes' experiences, knowledge, attitudes and opinions in relation to anti-doping activities. Forward conditional step wise logistic regression was employed on data from n=757 athletes to develop a model that discriminated supplement non-users from users. The model identified that British athletes most likely to use supplements were younger (under 23) males who were more likely to see doping as a problem in their sport and were more knowledgeable about testing procedures than their non-user counterparts. Post hoc analysis reinforced that non-users saw doping as less of a problem in their sport and were less knowledgeable about drug testing procedures relative to those using supplements. The pattern of results indicated gender-specific interventions on supplement use for young male athletes may yield significant benefits. The relationship between supplement use and perception of a doping problem suggested more work is needed to understand supplement use culture within sports. The relationship between knowledge of testing procedures and supplement use suggested further research is needed to see whether this is a positive or negative effect of detection-based doping deterrence activity.

Popular ergogenic drugs and supplements in young athletes

Ergogenic drugs are substances that are used to enhance athletic performance. These drugs include illicit substances as well as compounds that are marketed as nutritional supplements. Many such drugs have been used widely by professional and elite athletes for several decades. However, in recent years, research indicates that younger athletes are increasingly experimenting with these drugs to improve both appearance and athletic abilities. Ergogenic drugs that are commonly used by youths today include anabolic-androgenic steroids, steroid precursors (androstenedione and dehydroepiandrosterone), growth hormone, creatine, and ephedra alkaloids. Reviewing the literature to date, it is clear that children are exposed to these substances at younger ages than in years past, with use starting as early as middle school. Anabolic steroids and creatine do offer potential gains in body mass and strength but risk adverse effects to multiple organ systems. Steroid precursors, growth hormone, and ephedra alkaloids have not been proven to enhance any athletic measures, whereas they do impart many risks to their users. To combat this drug abuse, there have been recent changes in the legal status of several substances, changes in the rules of youth athletics including drug testing of high school students, and educational initiatives designed for the young athlete. This article summarizes the current literature regarding these ergogenic substances and details their use, effects, risks, and legal standing.

The use of dietary supplements and medications by Canadian athletes at the Atlanta and Sydney Olympic Games

OBJECTIVE

To learn more about the prevalence of dietary supplement and medication use by Canadian athletes in the Olympic Games in Atlanta 1996 and Sydney 2000.

SETTING AND PARTICIPANTS

Data were collected from personal interviews with Canadian athletes who participated at the 1996 Atlanta and 2000 Sydney Olympic Games. The athletes were interviewed by Canadian physicians regarding the use of vitamins, minerals, nutritional supplements, and prescribed and over-the-counter medications. Of the 271 Canadian athletes who participated at the Atlanta Olympics, 257 athletes were interviewed; at the Sydney Olympics, 300 of 304 Canadian athletes were interviewed.

MAIN OUTCOME MEASUREMENT

A quantitative and qualitative description of the use of dietary supplements by Canadian athletes at the Atlanta and Sydney Olympics.

RESULTS

At the Atlanta Games, 69% of the athletes used some form of dietary supplements, whereas 74% of the athletes used dietary supplements at the Sydney Games. Vitamins were taken by 59% of men and 66% of women in Atlanta, and 65% of men and 58% women in Sydney. Mineral supplements were used by 16% of men and 45% of women in Atlanta, and 30% of men and 21% of women in Sydney. Nutritional supplements were used by 35% of men and 43% of women in Atlanta, and 43% of men and 51% of women in Sydney. The most popular vitamins were multivitamins in both Olympics. The most popular mineral supplements were iron supplements. The most commonly used nutritional supplement in Atlanta was creatine (14%), but amino acids (15%) were the most commonly used nutritional supplement in Sydney. In Atlanta, 61% of the athletes were using some form of medication, 54% of the athletes were using medications in Sydney. Nonsteroidal antiinflammatory drugs (NSAIDS) were the most commonly used medications at both Olympic Games. Among all sports, the highest prevalence of vitamin use occurred in boxing (91%) in Atlanta and swimming (76%) in Sydney. Rowers (56%) and cyclists (73%) demonstrated the highest use of mineral supplements. Nutritional supplement use occurred most often in swimming (56%) and cycling (100%). The use of NSAIDs was highest in softball (60%) in Atlanta and gymnastics (100%) in Sydney.

CONCLUSION

This review demonstrates that dietary supplement use was common among Canadian athletes at both the Atlanta and Sydney Olympic Games. There was a slight increase in total dietary supplement use at the Sydney Games. Widespread use of supplements, combined with an absence of evidence of their efficacy and a concern for the possibility of "inadvertent" doping, underscore the need for appropriately focused educational initiatives in this area.

Dietary supplement use in adolescents

PURPOSE OF REVIEW

As prevalence rates of dietary supplement use are observed to be increasing in adolescents and the population in general, questions need to be asked about the efficacy, motivations, and consequences of such usage. Focusing mainly on individuals between the ages of 12 to 19 (adolescents) this review will highlight current prevalence rates, types of supplements being consumed, reasons for consumption, and concerns regarding physiological, psychological, knowledge transfer, and regulatory aspects of supplement use.

RECENT FINDINGS

Studies have indicated the prevalence of dietary supplement usage by adolescents range from approximately 10% to as high as 74%. Some of the highest rates of usage appear in chronically ill adolescents. Multivitamin and mineral preparations are the most common supplements being consumed; however, many studies indicate that adolescents are using other substances like creatine, herbals, or protein supplements. Some of the most appealing supplements among this age group are those that enhance athletic performance or physical appearance. Recent literature suggests three key moderating factors for supplement use in adolescents: health status, gender, and level of physical activity involvement.

SUMMARY

As the dietary supplement industry is now a multi-billion dollar industry, there is growing pressure, and a subsequent need for research to establish the efficacy and safety of these products particularly for adolescent users. The psychological and educational components of such use cannot be ignored as they play an equally important role in the health and safety of adolescents.