Sports Supplements & Performance | The Athlete’s Kitchen

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Sports Supplements & Performance | The Athlete’s Kitchen

Nancy Clark, MS, RD, CSSD |  Aug. 31, 2021

Recovery ACSM CEC

Sports Supplements & Performance EXPLAINED

Courtesy of Nancy Clark's The Athlete's Kitchen


     In their effort to enhance energy and optimize performance, many athletes purchase vitamins, herbs, amino acids, and other sports supplements that are reputed to offer a competitive advantage. While a few supplements (beta-alanine, creatine, caffeine, nitrates) might play a small role when added to a well-thought-out fueling plan, no amount of supplements will compensate for a lousy diet.

     Fundamental to every high-performance athlete is an effective sports diet. All athletes should be taught from an early age how to optimize their performance using the food-first approach so they know how to best fuel-up, fuel during, and refuel after challenging exercise sessions. Once an athlete has finished growing and maturing and has fine-tuned his or her fitness and performance skills, some sports supplements might be appropriately introduced with guidance from a knowledgeable professional.

     That said, to the detriment of their wallets, many athletic people look for a glimmer of hope from the multibillion-dollar supplement industry. Consulting with a registered dietitian (RD) who is board certified as a specialist in sports dietetics (CSSD) could easily be a better use of money.

Supplements are popular

     A survey of Division-1 college students (89 females, 49 males) at Arizona State University indicated 77% consumed at least one “claimed to be” ergogenic aid (1). Another survey of U.S. Army personnel reports 75% used some type of dietary supplement at least once a week. Protein/amino acids were the most popular, taken by 52% of subjects (2).

      Why are so many athletes willing to spend (or is that waste?) a great deal of money to buy sports supplements? The glimmer-of-hope reasons include: to improve physical appearance or physique, increase muscle mass, optimize general health, and help meet physical demands on their bodies. Unfortunately, most supplements don’t work. Before you spend your money, please educate yourself about each supplement you plan to buy.

Where to learn more

    For information about (supposedly) performance-enhancing supplements, the U.S. Dept. of Defense website Operation Supplement Safety offers abundant information for anyone who is curious to learn more.  The website includes:

• a list of at least 28 unsafe sports supplements to avoid.

• a list of questions to help determine if a supplement is safe. (Does the label have a “certified safe” seal from Informed Sport or NSF? Is the label free of the words blend, matrix, proprietary, or complex? Does it make questionable claims?)

• an A-Z index with info about specific supplements, with all you need to know about Adderall, apple cider vinegar, caffeine, creatine, energy drinks, ephedra, ketone supplements, nitric oxide, omega-3 fats, pre-workouts, pro-hormones, proprietary blends, plus many more.

• information on unusual reactions and adverse effects (nausea, headaches, shakiness, elevated heat rate, mood change, etc.) and how to report an adverse event to the FDA and the National Institutes of Health (NIH).


       Another helpful source of information is the Australian Institute for Sport’s ABCD Classification System. The system ranks sports foods and supplements into four groups according to scientific evidence and practical considerations that determine whether a product is safe and if it effectively improves sports performance.

Group A includes specialized products with strong evidence for benefits in specific events, including sports drinks, gels, iron, caffeine, beta-alanine, bicarbonate, beet root/nitrate, and creatine, among others.

Group B deserves further research. It includes food compounds with anti-oxidant and anti-inflammatory properties (i.e., tart cherry juice, curcumin), vitamin C, and collagen, to name just a few.

Group C lacks scientific evidence to support use. These include (and are not limited to) magnesium, alpha lipoic acid, HMB, BCAAs, leucine, vitamin E, plus more.

Group D includes products with a high risk of leading to a positive doping test: ephedrine, DMAA, herbal stimulants, pro-hormones, hormone boosters (such as DHEA, androstenedione, Tribulus terrestris), and others.


What supplements do “work”?

Sports supplements that do “work” actually improve performance by just a small (but potentially valuable) amount (3), despite carefully crafted advertisements that can lead you to believe otherwise. Case in point, the popular branch-chain amino acids (BCAAs), specifically the BCAA leucine, which is known to activate the muscle-building process. Unfortunately, simply activating the process is not enough to promote muscle growth.

     BCAA research indicates they do not provide any benefits above and beyond the amino acids athletes normally consume when eating protein-rich food at meals and snacks. To see any meaningful muscle-building effect, you actually need to have many other amino acids present (as happens when you eat real food, as opposed to an isolated amino acid), as well as enough calories—and of course, a good strength training program plus adequate sleep.


Varied responses

     Even among supplements that “work,” the response varies greatly from person to person. Case in point, beta-alanine, a supplement used by athletes such as sprinters, rowers, and wrestlers to reduce muscular fatigue and improve endurance during high-intensity exercise that lasts for one to four minutes. The varied responses can be related to not only genetics and biological factors, but also to the power of the mind, the placebo effect, adequate fuel, and enough sleep. Hence, when a supplement does “work” for some athletes, the response may be due not to the supplement, but rather to the athletes getting serious about taking better care of their bodies, eating wisely and getting enough sleep (4).

     Enhancing sports performance may not require rocket science after all.



Nancy Clark MS RD CSSD
Sports Nutritionist Nancy Clark, MS, RD, counsels both casual and competitive athletes in the Boston area (Newton; 617-795-1875). Her best-selling Sports Nutrition Guidebook and her online workshop can help you eat a winning sports diet. Visit for more information.


1. Vento KA, Wardenaar FC. Third-party testing nutritional supplement knowledge, attitudes, and use among an NCAA I collegiate student-athlete population. Front Sports Act Living. 2020 Sep 15;2:115. doi: 10.3389/fspor.2020.00115

2. Bukhari A, DiChiara A, Merrill E, et al. Dietary supplement use in US Army personnel: A mixed-methods, survey and focus-group study examining decision making and factors associated with use. J Acad Nutr Diet. 2021; 121(6):1049-1063.

3. Maughan R, Burke L, Dvorak J, et al. IOC Consensus Statement: Dietary Supplements and the High-Performance Athlete. Int J Sport Nutr Exerc Metab. 2018;28:104-125.

4. Esteves G, Swinton P, Dale C, et al. Individual participant date meta-analysis provides no evidence of intervention response variation in individuals supplementing with beat-alanine. Int J Sport Nutr Exerc Metab. 2021;31(4):305-313.