Sports dietitians are bombarded constantly with questions about supplements from athletes, parents, coaches, sports medicine physicians, and athletic trainers. It is important not to be an antisupplement person, but a proathlete person; therefore, the sports dietitian needs to make sure that what the athlete wants to take is not harmful, banned, or performance-impairing. That being said, it is important to ask the following questions when having the supplement dialogue with your athletes. Coleman has authored an excellent practice paper on evaluating dietary supplements (7) (Table 1).
As a starting point, it is important that everyone is speaking the same language when discussing supplements. What you may consider a supplement is not necessarily the same as what your athletes may think. Froiland (12) surveyed Division I student athletes about supplement use and asked athletes to define the term supplement. Responses included the following:
- Products that increase performance, strength, and muscle mass
- Products that enhance recovery
- Products that improve the health of the body
- Anything other than food
- Substances that help one to gain/lose weight
These responses indicate that there are many different substances that may come to mind when we ask our athletes about supplement use.
The study went on to ask questions about other types of products and the athletes' beliefs.
- Most athletes do not consider fluids and/or calorie replacement beverages to be supplements.
- Vitamins and minerals are considered to be an energy source.
- Caffeine and caffeine-containing products are considered to be sources of energy.
- Food cannot provide the "edge" that supplements can
The challenges in supplement educations are many. We are asked to be educators, counselors, enforcers, and health care providers. We also cannot dismiss the athlete's desire to pursue an advantage. Even if a product is deemed to be ineffective, if it is not harmful and the athlete feels better taking it, should we really discourage the athlete from using that substance? The problem with "no" is that the athlete will find someone who says "yes," and that person may not have the athlete's best interest in mind. It is our responsibility to educate athletes about the facts versus claims when discussing these products. As health care providers, we need to prevent abuse, overuse, or harmful side effects that could occur when our athletes mix preexisting medical conditions with supplements, mix prescription or over-the-counter medications with supplements, or take too many supplements simultaneously. Health care professionals need to be aware of the liability issues inherent in recommending any supplements. If an athlete has an adverse effect associated with supplement use, who is responsible? If an athlete fails a drug test, we may be held responsible or may be implicated, even though athletes are told constantly that if they take supplements, it is at their own risk. Health care professionals still need to proceed with caution when advising supplement use. Last but not least, we need to provide our athletes with ideas for options, be it different, less costly products, or increased reliance on food rather than supplements.
As a starting point we need to have the sports nutrition discussion with our athletes. Identifying performance-optimizing nutrition strategies may decrease dependence upon supplements. So what do your athletes need to know (Table 2)?
In addition, athletes need to understand that they eat food, not nutrients. For the most part, supplements are individual macronutrients (e.g., a protein isolate or carbohydrate-based gel) or micronutrients (B12). These are not complete food sources. Supplements cannot make up for deficient eating patterns. So an athlete who takes a lot of supplements but does not eat well has a well-supplemented, dreadful diet! Sport dietitians field many questions about supplements from parents of athletes. It is imperative to point out some of the hidden dangers of supplements, including allergy/food sensitivities, supplement-medication interactions, supplement-supplement interactions, and supplement-exercise interactions.
WHAT CAN THEY TAKE?
All supplements do not need to be dismissed, but rather, we need to educate our athletes about products that may have an ergogenic effect and that are safe. This includes the following items: sports drinks, sports gels, sports bars that contain carbohydrate, protein, and fat, some sports shakes, multivitamin-mineral supplements, and micronutrients, if needed.
Not all athletes are going to need to use sports drinks, gels, or bars. Sports shakes may be a convenient option post-exercise, but may be too calorie-laden for some athletes, and they are not inexpensive. Low-fat chocolate milk may be a great option, as a sports shake, in terms of taste and cost.
A multivitamin-mineral supplement is preferred over individual micronutrients. The exception to this is for athletes who may require additional iron, calcium, Vitamin D, or B12. Athletes need to be reminded that a vitamin is not a replacement for breakfast, and that vitamin supplements will not make up for a poor diet. When educating athletes about choosing a product, remind them that the vitamins in a product should not exceed 500% of the Daily Value (DV), and minerals should not exceed 100% of the DV.
There is no need for mega-dose supplements. Natural supplements are often more expensive but are not better for the body. In many cases, a store brand is as good as a name brand.
WHERE DO ATHLETES GET SUPPLEMENT INFORMATION?
As health care providers, we are the last on the list when athletes are asked where they get their supplement information. They find out about supplements primarily from magazines, their peers, trainers, coaches, and family members. You need to read what your athletes are reading. They don't do a literature review when choosing supplements. They read magazines like Muscle and Fitness, go to stores like GNC, or "surf the net." Although there is always the new product coming to the marketplace, some supplements remain more popular than others. They include creatine, protein powders, nitric oxide stimulators, fat burners, and anabolic agents. This article contains a review of some of the more popular supplements.
Creatine is produced in the kidneys, liver, and pancreas and ingested through the consumption of animal protein sources such as pork, beef, and fish. Creatine is a cell volumizer, increasing muscle fiber hypertrophy and cell volume (23). From a performance perspective, creatine may allow athletes to train harder and recover more quickly. However, some athletes are hyper-responders to creatine, while others are hypo-responders. This can be very frustrating for the athlete who sees teammates getting bigger and lifting more when his body doesn't seem to change at all.
Many athletes have been told that creatine is unsafe. There have been thousands of studies conducted on creatine's safety and effectiveness. The biggest issue isn't the safety of creatine, but that it doesn't work for everyone.
Creatine protocols range from 3-6 g·d−1 over 30 d to 20 g·d−1 for 5 d as a loading dose, and may improve work capacity (23). Doses of 3-6 g·d−1 for 28 d may result in an increase in fat-free mass and strength for the individual who is creatine-responsive (4). It takes about 6 wk for creatine levels to return to baseline after supplementation, so there is no need to take creatine continuously.
So does creatine offer an advantage? Yes and no. The athlete may be bigger, but since some of the weight gain is water, an athlete may complain of feeling "puffy." Increased weight may affect balance and agility adversely, which is not always an ergogenic advantage, especially for field athletes who need to be strong and fast.
Your athletes also need to know that they will get creatine in protein foods such as meat, poultry and fish - 16 oz of protein a day as beef, pork, or fish will provide 2 g of creatine. Although your athletes may not eat 1 lb of meat (16 oz) at one sitting, many of the athletes who choose to take creatine are already consuming significant amounts in their daily diet and probably do not need to be taking the supplement. In addition, if the goal is weight gain, then a protein-containing food will provide more calories than a creatine supplement. Although there are several forms of creatine, one is not more effective, just more expensive.
Many of my younger athletes ask about protein powders to help them gain mass. Athletes need to understand that there is an upper limit for protein, or the maximum usable amount of protein, which is 1 g·lb body weight−1·d−1.
There are several protein powders on the market, with enticing labels and photographs as well as Web sites. Athletes need to understand that the goal is to ingest adequate protein at the right time. The form is not as critical, that is, food derived or supplement derived. In this author's opinion, there is merit in adding a protein supplement to the diet of an athlete who is finding it difficult to meet protein needs through food alone, but that does not mean protein in place of food. The preferred type of protein supplement is a protein isolate instead of a protein powder. Whey protein isolate is an excellent source of the amino acid leucine, which may be more effective than other protein sources in muscle maintenance and growth. Whey protein isolate is very low in lactose and can be used by those with lactose intolerance; however, it cannot be used by those with a milk allergy.
Athletes also need to understand that the timing matters if they are considering a protein supplement. Muscle hypertrophy may be enhanced through consumption of 6-10 g of essential amino acids (12-15 g protein) with 35 g of carbohydrate before resistance training. The same protocol postlifts may stimulate net muscle protein synthesis (19) (Table 3).
AMINO ACID SUPPLEMENTS
Athletes ask about the use of individual amino acids, which they think will be more effective since the marketing implies quicker digestion and absorption. The fact is that it takes longer for the body to synthesize protein from amino acid supplements compared with protein-containing foods. In addition, they are very costly and may cause digestive distress (4).
Lack of energy is a problem that plagues athletes and nonathletes. There are countless products on the shelves promising to give the user more energy. They include energy drinks, pills, and blends. Athletes need to understand that the only way to energize the body is to consume calories. Although caffeine is thought to "energize" the body, it is a central nervous stimulant and does not contain calories. Ginseng is an herb that functions as an adaptogen to aid in immune system function, but it has no effect upon energy levels. The 5-h energy pills contain B vitamins, not calories, so they cannot "energize" the body. The body is energized by food calories.
Are there ergogenic advantages to caffeine? There can be depending upon the dosage and tolerance. Caffeine may improve reaction time and can allow athletes to train at increased speed and/or power output. The effects of caffeine are the same in males and females. Caffeine consumption may be advantageous for endurance athletes as it can expedite the use of free fatty acids as a fuel source earlier in exercise, therefore delaying fatigue by sparing muscle glycogen (5,18).
However, a little caffeine goes a long way. The ergogenic dose may be 1-3 mg·kg body weight−1 before and during exercise (8). There is no improvement in performance with higher doses. Too much caffeine can result in a myriad of side effects (Table 4).
ANABOLIC ERGOGENIC AIDS
Many athletes express interest in increasing muscle mass. Although eating enough calories is the main strategy for increasing mass, they may think that one cannot increase muscle size or strength through food alone. There are several products on the marketplace that are advertised to increase mass, with names such as Heavy Weight Gainer, Muscle Milk, and Muscle Tech among others. Many of these supplements contain ingredients that are banned in the NCAA, USOC, and professional sports. Minerals such as boron, chromium, zinc monomethionine aspartate (ZMA), and vanadium also are touted as being anabolic, but they do not increase muscle size or strength. Beta-HMB (beta-hydroxy-beta-methyl-butyrate) may increase muscle mass in combination with a strength training program, but it is very costly. If athletes want to increase mass, there is no substitute for strength training. Consuming more protein and eating pre- and post-lifts may do a better job at increasing mass and will be a lot safer as well (19).
NITRIC OXIDE STIMULATORS
These are some of the most popular products used by adolescent and college athletes with product names like NO Explode and Black Power. These products contain the nonessential amino acid arginine, which is combined with alpha keto-glutarate. The manufacturers claim that consumption of this product will increase muscle mass and strength. It has been hypothesized that arginine stimulates nitric oxide synthase release to catalyze arginine oxidation, resulting in nitric oxide release. Nitric oxide results in subsequent vasodilation and the "muscle pump" (14). Although there are minimal adverse side effects, there is no effect upon performance, and supplementation does not influence nitric oxide level concentration in the muscle. In addition, only one study has observed an increase in muscle strength with arginine-alphaketoglutarte supplementation, although there was no increase in muscle mass (6). Your athletes also need to know that these supplements are quite costly.
THERMOGENIC PRODUCTS (FAT BURNERS)
Athletes who need to lose weight may want to use fat burners to expedite the weight loss. The majority of these products are useless; however, some may be harmful, such as ephedra, which is a central nervous system stimulant. Although it is harder to find ephedra on the shelves, it can be purchased at some health food stores, distributors, and via the Internet. Your athletes may not know that the word ephedra or ephedrine may appear on a label as Ma Huang, ephedra, spitonin, or sida cordifolia. Products that are labeled as ephedra-free may contain the substance synephrine, also known as Zhi shi or citrus aurantium, bitter orange. Both of these products are banned by the NCAA, USOC, and professional sporting organizations. In addition, synephrine has a similar effect as grapefruit juice and therefore cannot be used with certain medications. Caffeine is not a thermogenic agent, even though it may be advertised as a fat burner. Green tea extract contains phytonutrients in the form of catechins and in particular epigallocatechingallate (EGCG) in addition to caffeine. Claims for the thermogenic effect of this product are based upon the interaction of the EGCG and caffeine to burn fat. Some studies demonstrate a metabolic boost associated with green tea extract, although it may be transient and not result in significant long-term weight loss (3,2,9,15). There also is some concern about hepatotoxicity with green tea extract supplements, and therefore use should be discouraged. (17). The FDA issued a warning to consumers on the danger of Hydroxycut products as there have been 23 reports of adverse events: liver damage, elevated liver enzymes, one case requiring a liver transplant, and one death in 2007 (20). Other reported adverse events include cardiovascular problems, seizures, and rhabdomyolysis (20). Although it is hard to know whether Hydroxycut causes health problems, it is a prudent recommendation to discourage athletes from using these products (20). Two other harmful products include Dieter's tea, which contains senna and cascara, two potent laxatives, and Star Caps, which contains furosemide. Other products with claims to burn fat (but don't) are Chitosan (13), L-carnitine (21), and Chromium (22).
SUPPLEMENTS FOR BONE AND JOINT HEALTH
There are several over-the-counter supplements touted to decrease inflammation and support healthy joints and bones. Certainly a diet with adequate protein and phytonutrients is essential, but there may be some supplements of benefit. Antiinflammatory agents include:
- Ginger: either as the root or in a 500-mg capsule form; gingerroot is an anticoagulant and may cause nausea if consumed on an empty stomach
- Omega-3 supplements: 1-3 g·d−1 with EPA, DHA, and ALA, to decrease synthesis of pro-inflammatory cytokines, inhibit COX-1 and Cox-2 enzymes, suppress synthesis of prostaglandins; E2 and arachidonic acid
- Pycnogenol (pine bark extract): 100 mg·d−1, which may decrease the amount of other antiinflammatory agents required
- Glucosamine/chondroitin: 500 mg glucosamine + 400 mg chondrotin sulfate TID or 750 mg glucosamine + 600 mg chondroitin BID
- Turmeric (curcumin): 400 mg TID + boswellia 300-500 mg·d−1
- Tart cherry juice: 8 oz·d−1; thought to inhibit COX-1 and COX-2 enzymes
- Digestive enzymes: bromelain, papaoin, trypsin, chymotrypsin; more effective for acute injury rather than chronic inflammation, but absorption can be a problem
In addition to calcium, optimal bone nutriture demands adequate protein intake, vitamins D and K in addition to vitamin C fluoride, iron, magnesium, manganese, and boron. This does not mean taking these micronutrients individually, but a multivitamin mineral supplement may be a prudent recommendation (Table 5).
HOW TO APPROACH YOUR ATHLETES
You need to know what your athletes take. Ask them to fill out a supplement form to obtain information on product, dose, frequency of use, and observations (Appendix). Remind your athletes that supplements are used to augment, not replace, the diet. Your athletes need to know that products that are banned by an athletic organization can still be sold, and the products that are natural are not always safe. Do talk about the cost and also potential contamination of supplements, in other words, that what the label cites is not always what's inside the bottle.
To keep your athletes safe, you need to educate them, their parents, and yourself about supplements. Do make use of resources, particularly sports dietitians, in addition to programs such as Drug Free Sport (www.drugfreesport.com) or NSF International (www.NSF.org). Do stress the importance of optimal fueling and hydration as the best ergogenic aid. Athletes need to understand the good and the bad when it comes to supplements, and they need to know that if they experience an adverse event, they should discontinue the supplement immediately and inform you as well. Helping our athletes navigate through the supplement maze is a part of our responsibility as a health care provider for athletes. When you have a dialogue about supplements with your athletes, think SHOP: safeguard health, optimize performance. In some cases, supplements may not be an option, and for other athletes, making room for the well-balanced nutritional diet is really the prescription they need to play well and be well.
Natural medicines comprehensive database: www.naturaldatabase.com
Consumer Lab: www.consumerlab.com
Drug Free Sport: www.drugfreesport.com
National Sanitation Foundation: www.nsf.org- testing program for supplements
www.ncaa.org: for list of banned supplements
www.wada-ama.org: for IOC banned substances
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