Diet+and+Athletic+Performance

=Athletic Performance Summary =

Diet is a factor in an athlete’s performance outcome. The foods an athlete eats are what fuel the burst of speed or endurance needed to push them ahead of an opponent. Diet provides the energy needed to exercise, train, and compete at peak performance. If an athlete is not consuming the proper amount and types of foods for their body and activity, they will perceive a marked difference in how their body functions in its execution of their sport. There is a mass of new information being researched on everything from macronutrients and micronutrients, to individual food products and what the best possible diet must include for optimal athletic performance. In the following summaries we will discuss some diet factors in recent nutrition headlines advertised to improve or enhance athletic performance. We will discuss the outcomes of research found opposing or supporting their inferences.

= = = = = = = = = = = = = = =Definitions =
 * **Amenorrea**- the absence of menstration in a woman of reproductive age
 * **Athletic Performance**- Carrying out of specific physical routines or procedures by one who is trained or skilled in physical activity. Performance is influenced by a combination of physiological, psychological, and socio-cultural factors.
 * **Exerices-associated muscle cramps**- painful, spasmodic, involuntary contractions of skeletal muscle during or immediately after physical exercise
 * **Electrolyte**- ions that are electrically charged and can be found in many sports drinks.
 * **Vasodilation**- widening of blood vessels

=**Nutrition Headline Critiques**=

===[|Peterson; Folic acid may boost vascular function for female runners; Nutraingredients.com] === The news article Folic Acid May Boost Vascular Function for Female Runners summarizes findings from a research done on female college or recreational runners. It studied the differences in brachial artery dilation between amenorrheic and normal menstruating runners. Researchers have found that amenorrheic athletic women have reduced blood vessel dilation similar to older postmenopausal women with established cardiovascular disease. Hoch says “the earliest sign of heart disease can be measured by reduced dilation in the brachial artery of the arm in response to blood flow. Reduced vascular dilation can limit oxygen uptake and affect performance.” The article is based from a study conducted to determine if folic acid supplementation increased dilation and endothelial vascular function in the amenorrheic runners (Lynch, 2010). Given 10 mg of folic acid a day for 4 weeks, this study showed that this supplementation improved the flow-mediated dilation of the brachial artery in amenorrheic runners by 4.7% +/- 2.2%, thus increasing circulation to the heart. The control group (normal menstruating runners) also was supplemented with 10 mg a day of folic acid but had virtually no change in their brachial artery dilation. Authors of this study failed to incorporate race diversity, as genetics are different and could have altered reactions to this study from ethnicity to ethnicity. This study had all white volunteers from the same community. The minimal amount of folic acid necessary for optimal results is uncertain and even though participants were supplemented with the same amount of folic acid daily, dietary folate consumption was not controlled. In addition, hydration status of these participants could have affected the absorption of folate since it is a water-soluble vitamin. Even though for the vast majority the health benefits of exercise outweigh detrimental effects, excessive exercise to the point of amenorrhea may hinder benefits and accelerate cardiovascular disease in women because of the decreased endothelial vasodilation in these women. The small dilation of vessels causes decreased blood flow, restricting the flow needed for critical muscles involved in exercise, including the heart (Dempsey, 2003). Several mechanisms exist to explain the effectiveness of why folate is used in this therapy: The endothelium of blood vessels uses nitric oxide to signal the surrounding smooth muscle to relax, thus resulting in vasodilation and increasing blood flow (Stryer, 1995). Folate participates in the production of nitric oxide by helping stimulate the endogenous regeneration of tetrahydrobiopterin, an essential cofactor of endothelial nitric oxide synthase. Folate also may have a direct antioxidant effect in the circulatory system, thus increasing nitric oxide bioavailability and improving vasodilation (Pajewski, 2009). This article titled Folic Acid May Boost Vascular Function for Female Runners is in my opinion more “noise” than "news" because it is merely displaying an exciting new study. It accurately states findings and accurately reports the information drawn from the original research. The title of this article is a little misleading because it does not specify that studies show it only benefits the amenorrheic runner. Also, another thing misleading in this article is how it states that “folic acid may not only boost heart health, but may also improve athletic performance for these women” without any reference showing studies done on actual athletic performances of these amenorrheic runners. This article is revealing a newer study and will need many more studies completed on this subject with altered methods, larger participants, more diverse race participants, etc. to more accurately pin-point optimal dose of folic acid needed for vasodilation benefits and WHO folic acid supplementation may benefit.

===﻿[|Bailey; Milk does a body good, especially athletes: research finds that milk may be better than sports drinks for serious athletes recovering from exercise, usnews.com] === The news article “Milk Does a Body Good, Especially Athletes” summarizes the findings of different research articles regarding milk as a recovery drink after exercise. The article also uses testimonials from individuals who work out often and drink milk instead of sports drinks after exercise. These athletes claim to feel a significant difference and improvement when drinking milk after exercise compared to sports drinks. The article proposes that milk is an ideal drink to promote muscle growth and regeneration after exercise. According to the article, milk also enhances athletes endurance to perform better during their next session of exercise after recovery. Milk is also claimed to help shed fat while building muscle, whereas sports drinks will help build muscle without promoting the body to loose fat ([|Josse 2010]). The article proposes that milk is superior to sports drinks in replacing fluid for the body. When compared to sports drinks milk has many more essential nutrients. Sports drinks are designed mainly to replace fluid, carbohydrates and a few electrolytes to the body. Milk however also includes many vitamins, minerals, lipids and proteins necessary to rebuild muscle after exercise. Drinking milk instead of sports drinks enhances cellular uptake of amino acids and in turn helps to stimulate muscle recovery ([|Elliot 2006]). Milk also helps the body retain liquids helping place the body in a positive fluid balance after exercise ([|Shirreffs 2007]). Whereas sports drinks or water may be excreted hours after ingesting returning the body to a negative fluid balance (Shirreffs 2007). The news article “Milk Does a Body Good, Especially Athletes” is accurate in its information and contents. Though some of its claims are over emphasized the information and claims are backed by sound scientific research. It is in my opinion that, due to the consensus of several independent experimental trials, milk is superior to carbohydrate replacement drinks after exercise. However due to the prevalence of milk/lactose allergies and intolerances it is not to be recommended to all populations. In my experience there is a significant number of athletes who become nauseas drinking milk after exercise or get stomach pains/discomfort. Therefore, it is important for athletes to decide for themselves what works best for them. Research trials do suggest that milk indeed does a body good, especially for athletes.

<span style="font-family: Arial,Helvetica,sans-serif;">[|Hattaway: The Truth About Protein: Menshealth.com]
<span style="font-family: Arial,Helvetica,sans-serif;">The news article The Truth about Protein summarizes some of the basic truths about protein and how much an athlete needs. The article talks about how muscle needs protein after a workout, and without protein, the workout is counterproductive. The main points covered in the article were how much and when to consume protein. The article begins by saying that one needs to consume more protein. The body will synthesize protein according to how active a person is, however, the max amount that can be consumed and synthesized in one sitting is 20g ([|Moore 2009]). Either young or old, the recommended dosage for athletes is the same amount ([|Sheffield-Moore 2004]). It also states that taking protein before and after a workout can enhance muscle growth and performance. <span style="font-family: Arial,Helvetica,sans-serif;">Most every athlete knows that when building muscle, or working out, it is essential for their bodies to consume protein. Tests show that young males reached a plateau of only 20 g of ingested protein ([|Moore 2009]). Additional amounts over 20 g did not delay or effect the ingestion of other nutrients in a 4 hour period ([|Moore 2009]). The tests are shown to be accurate for young males, however, further research showed that aging, per se, does not diminish the amount of protein synthesis in males ([|Sheffield-Moore 2004]). Studies also showed that ingestion of protein before (2 hours) and after a workout (immediately) did not enhance acute muscular performance over a short-term high intensity workout ([|Volek 2004]). <span style="font-family: Arial,Helvetica,sans-serif;">The article titled The Truth about Protein in my opinion is a mix of both “news” and “noise”. Though it gives factual information, the article still implies that taking the protein before and after a workout will increase performance and the studies do state that there was no difference between the two. It states clearly, that the body will only synthesize 20 g in one sitting but fails to mention that the duration of that time is four hours ([|Moore 2009]). In relation to an athlete and his performance the article is suggesting more protein than the body will synthesize. Protein may help with muscle growth, but more protein does not equal more muscle growth. Important to note, is that each study came from experimental human trials, which were all done with male subjects and in lab settings. The article was found in a men's magazine, so it is quite relevant for the intended audience and more news than noise.

<span style="font-family: Arial,Helvetica,sans-serif;">[|Inman;Vitamin B Deficiency and Poor Athletic Performance Linked; Medical News Today]
<span style="font-family: Arial,Helvetica,sans-serif;">The news article Vitamin B Deficiency and Poor Athletic Performance Linked examines the findings from a review written by Melinda Manore (who was cited in the news article) and Katherine Woolf on the effects of exercise on B vitamin requirements (Woolf, 2006). The article examines how B vitamins are used in metabolic processes such as energy-producing pathways as well as synthesis of new cells and repairs of damaged cells and assesses whether athletes, or specifically physical exercise, increases B vitamin needs (Woolf, 2006). One study cited by this review found that individuals with high deficiencies of vitamin B will find a significant decrease in athletic performance within only a few weeks (vander Beek, 1988). The authors use data from a double-blind, experimental human trial conducted with 23 healthy males to assess the effect of deficiencies in thiamin, riboflavin, and vitamins B-6 and C on exercise performance. They find a significant decrease (difference of 9.8 VO2 max) in aerobic power and physical performance within a few weeks of deficiency.

<span style="font-family: Arial,Helvetica,sans-serif;">B vitamins are involved in numerous metabolic processes. Niacin is essential for formation of the coenzymes NAD and NADP which are involved in over 200 reactions in the body. Riboflavin is important in glucose, fatty acids, and glycerol metabolism as well as energy formation. Thiamin is a key factor in the citric acid cycle and hexose monophosphate shunt, and is also needed for metabolism of carbohydrates, fats, and proteins (Driskell, 2009). These processes are extremely important in exercise, as well as everything that we do. Because of this, it would not be surprising that exercise increased B vitamin needs.

<span style="font-family: Arial,Helvetica,sans-serif;">The article titled Vitamin B Deficiency and Poor Athletic Performance Linked is in my opinion more "news" than "noise" due to the simple, yet relatively concise, way that the author reviews research on B vitamins in relation to exercise and energy pathways. It accurately reports information found in Melinda Manore's review on B vitamins and exercise, and includes information that consumers can use in order to find more information on the subject without making the article too confusing for them. Although research on the subject of B vitamin needs in relation to exercise is still being explored, this article does a good job at keeping consumers posted on new information without misleading them.

<span style="font-family: Arial,Helvetica,sans-serif;">[|Miller; Muscle Cramps: Don't Let Them Cramp Your Workout]
<span style="font-family: Arial,Helvetica,sans-serif;">The news article Muscle Cramps: Don’t Let Them Cramp Your Workout summarizes what exercise-associated muscle cramps are and what they may be caused from. Dr. Maquirrian states that “calves and feet, hamstrings, quadriceps, and triceps are the muscles more commonly affected by exercise-associated muscle cramps and that these muscles are often contracted during sports activities making them occur more during competition rather than in training.” He also said that delayed or nighttime cramps in fatigued athletes can also be associated with exercise. The article states that to help prevent muscle cramping, athletes should: be well conditioned for the activity, avoid dehydration, do routine and periodic stretching (particularly of affected muscle groups), maintain a well balanced diet to avoid fatigue during the exercise, and reduce the intensity and the duration of exercise if necessary. While this article states that doing these things will prevent muscle cramping there has been other research that explains why doing these things will not prevent but only delay the onset of exercise-associated muscle cramps (Schwellnus, 1997). <span style="font-family: Arial,Helvetica,sans-serif;">EAMCs are defined as “painful, spasmodic, involuntary contractions of skeletal muscle during or immediately after physical exercise” (Schwellnus, 1997). There have been many hypotheses about the onset and cause of EAMCs. Some of these hypotheses, as stated by Schwellnus, are (1) inherited abnormalities of substrate metabolism (metabolic theory), (2) abnormalities of fluid balance (dehydration theory), (3) abnormalities of serum electrolyte concentrations (electrolyte theory), and (4) extreme environmental conditions of heat or cold (environmental theory).The onset of exercise-associated muscle cramps (EAMCs) is associated with many factors. Research has shown that keeping hydrated before, during and after exercise may help delay the onset of EAMCs but that dehydration is not a sole cause of EAMCs (Jung, 2005). There are other factors such as diet and genetics that can play a role in these EAMCs (Jung, 2005). Other research has shown through electromyography (EMG) recordings of the cramping muscle groups that increased EMG amplitudes in these worked muscles appear to support that EAMCs may be accompanied by heightened neuromuscular activity possibly associated with muscle fatigue and is not related to hydration status (Sulzer, 2005). Another article that supports these results reviewed a study done on 1300 marathon runners and concluded that EAMCs are caused by muscle fatigue that alters motor neuron control at the spinal level through abnormal reflex activity (Schnellnus, 1997). <span style="font-family: Arial,Helvetica,sans-serif;">The article Muscle Cramps: Don’t Let Them Cramp Your Workout is in my opinion more “news” than “noise” due to their accuracy in defining what exercise-associated cramps are, what they may be caused from and what things can help prevent or delay them. Though they did use the word “prevent” in their article[,] I do still feel that in doing those things such as stretching, keeping hydrated, and maintaining a healthy diet would help towards at least delaying the onset of the EAMCs. More research is needed in understanding the precise mechanism involved in altered reflex activity that may be causing EAMCs.

=**Conclusion**=

<span style="font-family: Arial,Helvetica,sans-serif;">Results from our discussion conclude that, in reference to athletes, there are many diet factors professed to amplify and boost athletic performance outcomes. Although they might have started out from scientific evidence, they have often been distorted to fit a particular company or individual’s interest for marketing and selling of their products. While there is scientific evidence showing milk to be a superior exercise recovery drink compared to water or sports drinks, claims/benefits are often exaggerated in the media and results are not applicable to all populations. Protein also has shown to have scientific evidence in relation to athletic performance and positive effects of supplementation, however there is a cap and excess protein has little to no effect. After reviewing original research, folate supplementation only benefits amenorrheic female runners specifically but has been able to draw conclusions that it results in an increase of blood flow to vital organs during exercise, resulting in enhanced performance. We have also shown that B-vitamins have also been shown that supplementation may help improve athletic performance when there is a deficiency present. There are many hypotheses pertaining to the cause of exercise-associated muscle cramps but research suggests that they are mainly due to muscle fatigue. Much research is still needed to fully understand the cause of these cramps. Research does show though that stretching, keeping hydrated, and maintaining a healthy diet would help towards at least delaying the onset of the EAMCs. We have shown that athlete consumers must pay close attention to actual evidenced research before purchasing products or listening to nutrition advice from news articles and headlines.

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