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.Key Words: ergogenics, Dietary Supplement and Health Education Act, World Anti-Doping AgencyFoods and dietary supplements have been used to enhance health and athletic performance (ergogenics) since the early Olympic Games. Today, athletes at all levels of competition continually work to improve performance, and many consider the use of dietary supplements or engineered foods to gain an additional performance edge or health benefit. This may concern health care professionals because athletes may receive advice and feel pressure from many well-meaning supporters and advocates. However, athletes can be vulnerable to misinformation and risk in terms of the safety, legality, and efficacy of dietary supplements.Although determining overall rates of supplement use among athletes is difficult, estimates of use by collegiate, high school, and middle school athletes have been reported in the literature.^1–6 In a 2004 study by Burns et al,¹ 88% of the collegiate athletes surveyed used 1 or more nutritional supplements, yet the perceived efficacy of those supplements was only moderate. Athletic trainers (ATs) were their primary sources of nutrition information and were perceived to have significant nutrition knowledge. The 2012 “Substance Use” report compiled by the National Collegiate Athletic Association (NCAA) presented survey data from 20 474 US athletes and compared those data with 2005 outcomes.⁷ Although survey data are limited by the perceived anonymity of the results, they can be useful to better understand trends and potential risk factors.The overwhelming industry presence and advertising appeal likely has strong influence on athlete choices. According to the 2011 “Sports Nutrition and Weight Loss Report,”⁸ 9% annual sales growth and $22.7 billion in total sales were noted for sports nutrition and weight-loss products in 2010. Energy drinks and shots (small containers of concentrated product) were the primary product category ($12 million) and were purchased through mass channels. A December 2010 press release from the US Food and Drug Administration (FDA) regarding methylhexaneamine, which has been identified as the “new ephedra” (stimulant), anticipated continued reports of adverse events, failed drug tests, and product recalls. The release also cited consumer-trust issues in the supplement industry and the joining of forces by the FDA and major trade organizations to “clean up” the industry. Obviously, health care practitioners need to be aware of the trends in supplement use and the risks the supplements may carry for athletes'' health and sport eligibility.As health care professionals, ATs must be knowledgeable regarding basic nutrition and supplement use and must be able to educate their athletes regarding the efficacy, safety, and legal issues associated with the use of supplements. If they are not knowledgeable in these areas, ATs must be aware of resources for education and proper referral, so they can provide guidance for those within the athletic community. This position statement provides suggested resources to help ATs stay current in the ever-changing landscape of dietary supplements.To formalize the position statement objectives into recommendations, we used (where appropriate) evidence-based review and the Strength of Recommendation Taxonomy (SORT) criterion scale (9 and adopted by the National Athletic Trainers'' Association. Some of the educational materials regarding dietary supplements are found in federal law; these are noted in the recommendations.

Table. Strength of Recommendation Taxonomy (SORT)^a

Magnitude and time course of changes in maximal oxygen uptake in response to distinct regimens of chronic interval training in sedentary women

Purpose

This study aimed to compare changes in maximal oxygen uptake (VO_2max) in response to two regimens of chronic interval training.

Methods

Twenty healthy sedentary women (mean ± SD age and VO_2max = 23.0 ± 5.7 years and 30.1 ± 4.4 mL kg^?1 min^?1, respectively) were randomized to complete 12 weeks of one of two interval training regimes, while an additional seven women served as controls. Training was performed 3 days week^?1 on a cycle ergometer and consisted of 6–10 bouts of 1 min duration at lower (60–80 % W _max = LO, n = 10) or more intense (80–90 % W _max = HI, n = 10) workloads separated by a brief recovery. Every 3 weeks, measures of VO_2max and W _max were repeated to assign new training intensities. Changes in blood pressure and body composition were also examined.

Results

Data revealed significant (p < 0.001) improvements in VO_2max in LO (22.3 ± 6.9 %) and HI (21.9 ± 11.6 %) that were similar (p > 0.05) between groups. Approximately 60 % of the increase in VO_2max in HI was observed in the initial 3 weeks, compared to only 20 % in LO. No change (p > 0.05) in body weight or body composition was revealed in response to training. Results demonstrate that a relatively prolonged regimen of moderate or more intense interval training induces similar improvements in cardiorespiratory fitness, although HI induced greater increases in VO_2max early on in training than LO. Completion of more intense interval training may be an effective means to expedite increases in VO₂max soon after initiation of exercise training.     

Failure to show mycoplasmas and cytopathogenic virus in rheumatoid arthritis.

Synovial needle biopsies, joint aspirates, and joint tissue obtained at open operation from 41 cases of rheumatoid arthritis were inoculated onto PPLO media, L-form medium, and cell cultures for the isolation of mycoplasmas, L-form bacteria, and viruses. Medium suitable for the isolation of 'T' strain mycoplasmas was not employed. No mycoplasmas, L-form bacteria, or cytopathogenic viruses were shown. Similar specimens from nine patients diagnosed as having Reiter's disease were examined in a like manner and yielded only one Mycoplasma hominis type 1 isolate from a knee joint biopsy. It is concluded that known strains of mycoplasma and bacterial L-forms do not play a direct role in early and established cases of rheumatoid arthritis. Some of the cell cultures used in this study contained mycoplasma contaminants. Bacterial contaminants were also encountered in occasional batches of L-form medium.     

Longitudinal correlations between MRE,MRI-PDFF,and liver histology in patients with non-alcoholic steatohepatitis: Analysis of data from a phase II trial of selonsertib

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