And The Nutrition Of Athletes Essay, Research Paper
Currently, I believe that many of the (ENTER YOUR SCHOOL) athletes do not adjust their diets to enhance performance, which can come about with proper nutrition. The nutrition of athletes is extremely important affect on their performance. At some period in an athlete s career they will find a decrease in performance as a result of nutrition related difficulties. By choosing sound eating habits problems such as decreased endurance, reduced speed and impaired concentration may be prevented and will promote optimal performance. (Coleman & Steen 11) `Making the proper nutrition choices is as important as the choosing the right training program . (Coleman & Steen 1). For such a reason I carried out this research project to find what adjustments, if any, are made by the athletes of this college. Generally, I went about my research project by handing out 50 surveys to athletes from sports varying from Basketball, Tennis, Cross-Country, Rodeo, Golf, Baseball and Volleyball. Each of these surveys required the athletes to write down what they ate over a 5-day period and also asked various questions regarding their nutritional habits. Overall, the results tended to support my hypothesis (as there were many factors of the diet that were analyzed) that various improvements could be made to the diet of athletes to enhance their performance.
This research project is one that brought great interest to me, as I am a student athlete myself and I also hold a strong interest in the field of Nutrition. After I graduate I hope to complete further study and gain my masters in Nutrition. This topic also runs into strong correlation with Kinesiology. Kinesiology refers to the movement patterns of the human body and thus runs into a strong tie with energy demands of the body. It is important that these energy demands are met especially in exercise. The main reason is that what we eat and the energy that is metabolized from this food is responsible for our everyday activities. Especially, for those athletes that are involved in rigorous training on a regular basis.
First, I will discuss the research methods that I used in finding the relevant raw data. I will then go onto discuss how I collected, organized and analyzed the data and how I gained these results. The methods that I used included handing out surveys to 50 (ENTER YOUR SCHOOL) athletes. Each survey consisted of a daily nutrient intake form, which covered 5 days. This enabled me to analyze the average intake of various nutrients by the sample of the (ENTER YOUR SCHOOL) athletes. It also contained various questions regarding alcohol, skipping meals and their intake of fast food.
The sample that I chose was random, I did this by handing out the surveys to athletes from different sports and I also handed them out at different places. This enabled each student-athlete to hold an equal chance of being selected. After 6 weeks I chose to analyze the surveys that I had received back. There were 21 surveys returned which meant that sample chosen made up 14% of the total student athlete population.
The next step was analyzing the surveys, the 5 day nutrient intake from each athlete was analyzed by using a Nutrition program on one of the library s computers. This provided an analysis of the average intake over 5 days. Included in this was a wide variety of information ranging from total caloric intake to whether particular vitamins met the Recommended Daily Allowance (RDA). Out of the information provided I chose those nutritional areas that play an important role in athletic performance. From this I was able to gain a mean (average) from the 21 athletes for each area. The standard deviation was then calculated, which enabled me to determine the Level of Confidence for each statement that was made regarding the various areas of nutrition. The calculations for this involved the mean as well as the Standard Deviation. After this I referred to Table 6.1 (Vincent, P.81), to determine which level of confidence would be most appropriate for each nutritional area.
After analyzing the intake of nutrients over 5 days I also analyzed the replies to other questions included in the survey. This enabled me to calculate percentages regarding alcohol consumption, fast food intake and the skipping of meals.
I will now discuss exactly what makes up proper nutrition and what enhances athletic performance. The results from this study will also be tied in with this discussion. This will enable contrasts and comparisons to be made between ideal nutrition for enhancing athletic performance and that of the (ENTER YOUR SCHOOL) athletes.
The first class that I will discuss is Carbohydrates. This class of nutrients are the most readily available source of food energy. This is because all carbohydrates are gradually broken down to simple sugar glucose through digestion and metabolism, and are used as the body s primary energy source. Glucose in its stored form is called glycogen and is found in the liver and muscles. The main fuel for most sports is muscle glycogen and a diet high in Carbohydrates is necessary to maintain this. Complex Carbohydrates are the main emphasis of a high performance diet. These can be found in foods such as beans, pasta, rice, vegetables, bread and cereal. These food types also provide other essential nutrients such as vitamins, minerals and proteins, and hold four calories per gram.
Carbohydrates play a major role in performance and almost all athletes will come across problems in their performance as a result of inadequate carbohydrate intake. Their performance may be affected in a `reduction in speed, impaired endurance and difficulties concentrating. ( Coleman & Steen 6). `Depending upon the intensity and duration of the sport that the athlete is involved in there should be a consumption of 6-10 grams of carbohydrates per kilogram of body weight. ( Coleman & Steen 17). These can be gained through a high intake of fruits, grains and vegetables. These are all high in carbohydrates and low in fat. Athletes should consume around 60% of their total caloric intake from carbohydrates.
After carrying out this study on a random sample of the athlete population, it seems to be particularly clear that the carbohydrate intake does not meet the recommended percentage of total caloric intake that enhances performance. The mean of the percentage that carbohydrates make up of the total caloric intake was only 48.5%. There is a 95% Level of Confidence that the percentage of caloric intake that carbohydrates makes up lies between 45% and 52%. This is extremely low and proper carbohydrate consumption in the diet of an athlete is important. An example of this is an experiment that was carried out among three groups of runners. `A classic report compared fuel use during physical activity among three groups of runners, each on a different diet. For several days before testing, one of the groups ate a normal mixed diet (55 per cent of calories from Carbohydrate); a second group ate a high carbohydrate diet (83 per cent of calories from carbohydrate); and a third group ate a high fat diet (94 percent of calories from fat). The results of the test showed that the high carbohydrate diet increased the endurance of the athletes, the maximum endurance times was 167 minutes. The maximum endurance time for the normal mixed diet was 114 minutes and the high fat diet was very low at 57 minutes.(Sizer and Whitney 383) This study showed that a high carbohydrate diet enhances an athlete s endurance by ensuring ample glycogen stores and how there is a need for increased carbohydrate intake by (ENTER YOUR SCHOOL) student athletes.
The second class of nutrients is Fats and these are extremely high in energy. However, they are quite often labeled as empty calories. This is because they carry 9 calories per gram of fat and quite often hold very low amounts of vitamins and minerals. However, fats are important because they are responsible for insulation and protection of the body s major organs against trauma and exposure to cold. `Fats also provide the body with their only source of Linoleic acid which is essential for growth, healthy skin and hair .(Coleman & Steen 3). Fats also are important in the absorption and transportation of fat soluble vitamins.
Fats are divided into two categories; saturated and unsaturated. It is important that foods high in fats, saturated fats, cholesterol, sweets and alcohol are restricted especially for those athletes who are desiring a lower body weight. The amount of calories obtained from fat should be approximately 20-30 % of total caloric intake. Less than 10% of this should come from saturated fats as these types of fats increase the cholesterol levels. After analyzing the saturated fat intake, it appears that it is a little high for the athletes as the average was at 108% of the RDA, with the greatest intake being at 197% of the RDA. There is a 95% level of confidence that the RDA of saturated fat intake of LCSC athletes lies between 85% and 122%. The overall intake of fats by the athletes studied also seemed to be a little higher than the recommended percentage. The average of percentage of fat intake from the total calories consumed was 32%. Although this is not drastically over the recommended percentage it is a little high. The range of athletes fat intake lies between 28% and 35% of the total caloric intake and this is calculated with a 95% level of confidence.
A different result that was obtained from the surveys was that regarding fast food consumption. The results showed that 14% of the sample studied ate fast food 5 to 6 times a week, while 38% ate fast food 2 times a week. The remaining 48% ate fast food only on occasions. These results are of some concern as quite often many fast foods are high in fat. A diet high in fat is quite often restricting to the performance of an athlete. This is clear after the study that was mentioned earlier involving the marathon runners. Another fact that is also important is that fat is only broken for energy in one way and this is through aerobic metabolism. This means that `when the intensity of the activity becomes so great that energy demands surpass the ability to provide energy aerobically, the body cannot burn more fat. Instead, it burns more glucose. (Sizer and Whitney 387) In some cases it is believed that high fat diets promote performance in endurance athletes. The reason for this belief is because fat stores are more plentiful, whereas glycogen stores are more restricted. However, eating too much fat is more likely to decrease performance. Eating too much fat will cause a decrease in carbohydrate intake. This in turn will deplete glycogen stores found in the muscles because they cannot be maintained on a high fat diet. The preferred source of fuel in high intensity exercise is muscle glycogen over fat because fat breakdown can not supply energy fast enough. `Most athletes train at an intensity that requires carbohydrate for fuel. (Coleman and Nelson. 72)
Protein is a different class of nutrients that are essential in the diet of an athlete. An athlete should consume between 1 and 1.5 grams of protein per kilogram of body weight each day. This is quite a bit higher than the recommended 0.8 grams per kilogram of body weight for sedentary people. This is recommended by both, the American Dietetic Association and the Canadian Dietetic Association. ( Sizer and Whitney. 391). More specifically endurance athletes, such as those involved with Cross-Country, should have 1.2gm per kg daily and may also benefit from 1.4 gm per kg while carrying out prolonged endurance activity. This is to support increases in the aerobic enzymes (proteins) in the muscle, red blood cell formation and the formation of myoglobin. Strength athletes require 1.2 grams per kg and may gain increased results by a slight increase in the intake of protein during periods of muscle building. The growing athlete requires more protein than the adult athlete, this brings age in as a factor as well. Generally, a total of 12-15% of the total caloric intake should come from proteins. ( Sizer & Wagner 57-59). The calculations obtained from the surveys showed that the mean percentage of the protein intake of the total calories consumed fell closely with the recommendations for athletes, which is 16%. It was calculated at a 90% level of confidence that the percentage of Protein of the total calories lied between 15% and 17%.
These results are important as Protein is needed in the diet by the athlete to provide the needed amino acids that are essential for the synthesis of new muscle proteins. Protein in the diet is also needed as a fuel for energy. It contributes to about 10 per cent of the total fuel used. There is a smaller amount used by moderate exercisers. The amount used during exercise is also strongly related with what other nutrients constitute the rest of the diet. A diet that is high in Carbohydrates spares proteins being used as fuel for energy. A different factor that affects the use of protein for an athlete during exercise is , the better trained athlete the less protein that is used at a particular intensity.( Sizer and Wagner 391).
Although, the calculations earlier showed that the total percentage of protein intake fell within the proper range, it seems that there is a general increase over the recommended daily allowance for each of the athletes. The mean lied at 149% of the recommended daily allowance (RDA) for protein. This area was calculated at a 95% level of confidence that the protein intake of the (ENTER YOUR SCHOOL) athletes lies between 139% and 159% of the RDA. Although a slight increase over the RDA is beneficial to athletes as mentioned earlier, it is of some concern when protein intakes lie well above the RDA. Protein is an area that has recently been of great debate. This is because `many body builders and strength athletes believe that they require increased amounts of protein to perform at their best . (Coleman and Steen 57). Many of these athletes believe and are told that a high protein diet and the intake of protein supplements, will increase their muscle mass and thus improve their potential for strength development. This has been very popular among sports such as Basketball and Football, where increased muscle mass enhances performance. Although athletes do need an increase of protein over the adult recommended daily allowance; `There is no evidence that protein supplements enhance muscle development, strength, or endurance. Extra protein doesn t help and may hurt health and performance. (p.63, Coleman and Steen). These supplements quite often displace nutrients such as Iron, Niacin and Thiamin that are found in high protein foods such as fish. When too much protein is consumed the excess protein is either used as energy or is converted to fat. It also increases the body s water needs and this may lead to dehydration. The main reason for this is because the kidneys require more to eliminate the excessive nitrogen load that comes with an increased protein intake. This means that athletes on such a diet should drink extra fluids to prevent becoming dehydrated.( Coleman and Steen 63-64).
A high protein diet is usually accompanied with a high fat intake. By consuming such foods after heavy training it will cause an incomplete replacement of muscle glycogen and will thus impair performance. There are other side effects to a high protein diet. `Large intakes of some amino acids may interfere with the absorption of certain amino acids. (Coleman and Nelson 64). Other side effects such as stomach cramping and diarrhea may occur. A different problem with a high protein intake is that it can also prevent proper calcium absorption by the body. The higher amount of protein the diet the higher the calcium content in the urine. This can lead to diseases such as osteoporosis later in life.( Hoeger & Hoeger 64 ).
Another class of nutrients that was studied was water, which is essential, and plays a huge role in performance. Water has many functions and its `most critical function for athletes is the regulation of body temperature. ( Coleman & Steen 85). It is important that as exercise levels increase that water intake also increases. As the body temperature increases with exercise, sweat is released to try and cool the body. `Over time, and especially in hot weather, this excessive sweating can lead to dehyrdration. ( Williams300.) About 65% of water is stored inside the cells and the remainder is stored outside the cells. `Proper water and electrolyte balance within these areas is extremely important for athletes. Fluid shifts such as decreases in the blood volume and cellular dehydration can occur from sweat losses during exercise in the heat. Dehydration contributes to fatigue and increases the risk of developing heat illnesses. ( Coleman & Steen 86). `The loss of water in sweat harms athletic performance and hinders the body s ability to control body temperature. ( Coleman & Steen 86). Dehydration results in the athlete not being able to exercise for as long and or as hard. `The athlete who arrives at an event even slightly dehydrated starts out at a disadvantage. Even a mild water loss can play a huge part and `a water loss of even 1 to 2 per cent of body weight can reduce a person s capacity to do muscular work. A person with a water loss of about 7% is likely to collapse . ( Sizer & Whitney 404).
In order to prevent these negative effects upon performance, it is important that athletes exercise during the coolest part of the day (if possible), and also drink plenty of fluids leading up to and after the exercise. It is recommended that `at rest, athletes need between 2 and 3 quarts of fluid daily. ( Coleman &Steen 91). A smart way for athletes to prevent dehydration is to drink extra fluids 3-4 days before an event. Even though this fluid is not stored in the body, drinking this extra fluid ensures maximum hydration of the tissues for the beginning of the event. Drinking plenty of fluids afterwards is also essential to one s health. After an athlete exercises `it is wise to note the change in body weight and drink two cups of water for every pound lost. ( Hegarty 305.) In preparing to exercise in the heat athletes should drink 8 to 16 ounces of rapidly absorbed fluid 15 minutes before exercise. This is known as hyperhydration and it lowers the body temperature and thus reduces the stress that heat may place on the cardiovascular system. `Athletes will perform at their best when their fluid intake closely matches their fluid losses from sweating. ( Coleman and Steen 92.) This is important when water can makes up as much as 70% of the body weight in muscular athletes.
Clearly, water is an extremely important nutrient in the performance of all athletes. However, it appears after studying the surveys that there is a large intake of alcohol by many of the athletes. After analyzing the surveys an average of 18.76 grams of alcohol was consumed on a daily basis. Alcohol made up 5.9% of the total caloric intake. At a 90% level of confidence it appears that the percentage of alcohol of total calories consumed by (ENTER YOUR SCHOOL) athletes lied between 4% and 8%. Of the 21 athletes that participated in the survey, 7 did not consume any alcohol over the 5 day period. A total of 19% said that they never drink, while 38% said that they drink only on occasions. There was 14% that drank once a week, 19% that drank twice a week and 10% drank 3-4 times a week. From the percentage of those that drank, 59% consumed only beer, while 35% consumed beer and liquor, and 6% consumed only Liquor.
The intake of alcohol by these athletes plays a huge role in their performance. `Drinking too much alcohol before exercise (even the night before) can harm performance. (Coleman & Nelson 98). Alcohol greatly speeds up water losses because it acts as a diuretic and increases urine output. `The dehydrating effect of alcohol impairs performance and increases the risks of heat illnesses during exercise in warm weather . (Coleman & Steen 98.) If an athlete is to drink alcohol before exercise it greatly decreases the output of glucose by the liver, causing low blood glucose and early fatigue. Alcohol does not contribute to the formation of muscle glycogen which is the primary fuel for exercise. The nutrient qualities in alcohol are also very low and are high in calories, thus making them a high source of empty calories. It s consumption also affects the absorption of other vitamins. `Chronic or abusive use of alcohol can interfere with absorption and use of B-complex vitamins, especially Thiamin, and even destroy Folate (folic acid). (Williams 107). Alcohol also reduces motor skills that are important in performance such as coordination and balance.
A different substance that acts as a diuretic is the caffeine found in coffee, teas and also in some sodas. This is extremely relevant because the random sample of athletes studied consumed a daily average of 58.05 mg of caffeine. A range between 43mg and 73mg was calculated for the daily intake of caffeine by LCSC athletes at the 90% level of confidence. This intake came about through either pop or coffee. It is important that athletes who consume such beverages are aware of the need to increase their fluid intake so as to account for the dehydration that may occur. Although Caffeine acts as a diuretic it is believed that it can enhance performance by `consuming 5-9mg of caffeine per kg prior to endurance exercise, it may enhance performance by sparing muscle glycogen. ( Coleman & Steen 66). Studies have also shown that epinephrine levels are raised through caffeine consumption and this stimulates the release of free fatty acids from the adipose tissue. `This increases fat utilization and reduces muscle glycogen usage. ( Coleman & Steen 66). `However, the use of caffeine is considered a form of doping by the International Olympic Committee.’ (Coleman & Steen 66).
Other classes of nutrients include Vitamins and these also play an important role in performance. Thiamin, Riboflavin and Niacin all play `key roles in energy release .( Sizer & Whitney 39). However, extra amounts do not provide any advantage. In actual fact an excess of Niacin of the RDA may suppress the release of fatty acids, and force muscles to use extra glycogen during physical activity. This may shorten the time to Glycogen depletion and may increase the difficulty of the work. Vitamin B6 and B12 are also believed to be beneficial. `Vitamin B6 plays key roles in the release of energy from Nutrients, in the liberation of Glucose from Glycogen, and in the formation of Hemoglobin. ( Sizer and Whitney 396). After the 5 day analysis it seems clear that there is a slight deficiency of Vitamin B6 as the average was 89% of the RDA. It was calculated at the 90% level of confidence that the intake of Vitamin B6 lied in the range of at 78% and 99% of the RDA.
Vitamin B12 is also believed to play an important role with its involvement in the production of red blood cells. The intake of vitamin B12 seemed very high as an overall daily average of the athletes as 186% of the RDA was obtained. Although, it may seem that an increase in such a vitamin may enhance performance it actually does not affect performance. The only vitamin that this is applicable to is Vitamin E as an increase over it s RDA may enhance performance. Vitamin E is especially important with Endurance athletes. This is because `During endurance events, the cells use great quantities of oxygen to process fuels and Vitamin E rigorously defends the cell membranes against oxidative damage. ( Sizer & Whitney 395). After studying the surveys it appears that the (ENTER YOUR SCHOOL) athletes consume 110% of their RDA for Vitamin E. Although this may be a little high of the RDA it may actually improve performance.
There are some minerals that play a role in performance and an important one is Iron. `Endurance athletes especially women athletes are prone to iron deficiency . The effects that this has upon performance is that an `Iron deficiency impairs performance because Iron helps deliver the muscles oxygen. ( Sizer & Whitney 397). The aerobic work capacity is reduced with iron reduced oxygen delivery, so the individual fatigues quickly. Calcium is a different mineral that is essential for replacement by athletes. The main reason for this is in increasing bone density for the prevention of osteoporosis later in life. Light physical activity is beneficial to bone health yet `extremes in physical activity may be detrimental to bone health . (Sizer & Whitney 397). Many of the athletes involved in this study undergo rigorous physical activity and if calcium intakes are low they may become susceptible to stress fractures and osteoporosis. By obtaining adequate calcium intakes it will protect athletes against later bone loss. However, after analyzing the nutrient intake of athletes the mean of the daily average was only at 84% of the RDA. The range lies from 73% to 93% of the RDA by athletes and this lies at the 95% level of confidence.
Other minerals also play an important role and one is Potassium. Many athletes lose potassium through profusive sweating which comes about through rigorous activity. The nutritional analysis discovered that only 68.3% of the RDA was being met by the sample of the (ENTER YOUR SCHOOL) athletes. There is a 95% level of confidence that the intake of Potassium by athletes lies between 60% and 75% of the RDA. Another mineral that is also important is Sodium. Large amounts of Sodium are also lost through sweating, however increased Sodium intakes may be bad for health. This is because it may greatly increase the risk of suffering from hypertension at later periods in life. It appears that the average sodium intake by the athletes was a little high at 138% of the RDA being obtained. The range for Sodium intake lies between 118% and 157% of the RDA, this is determined at a 95% level of confidence. Although this may not be a problem now, it is important that proper habits are set for later in life so as to prevent the onset of any diseases such as hypertension.
Each of these classes of nutrients are responsible for energy production as the `body extracts the required energy from either dietary or body stores of carbohydrate, fat and protein to rebuild the energy rich ATP. (p.24). Adenosine triphosphate (ATP) is an energy rich chemical compound that is used for all processes that require energy within the cell. The energy that is released is used for all body functions and these include muscular contractions. Energy is also derived from Creatine phosphate and it provides a small reserve of quick energy. It is the breakdown of these two molecules that provide energy necessary in all-out exercise for about 6-8 seconds, such as the 100 meter dash.
A balanced energy supply is necessary throughout the day for athletes. This comes about through regular eating and the intake of all three meals. The most important of these three meals is breakfast. If an athlete does not consume breakfast a decrease in performance will result. This is because there will be a low blood glucose level as the `overnight fast lowers liver glycogen stores.’ (Coleman & Steen 35). With depleted liver Glycogen stores an athlete’s blood sugar drops and may feel fatigued and light headed. By an athlete eating a high carbohydrate breakfast `before morning exercise it will help to maintain blood glucose levels so that an athlete can perform at their best.’(Coleman & Steen 35). It appears that the regular intake of meals is another area where performance may be affected by the athletes at (ENTER YOUR SCHOOL). After analyzing the surveys it appears that 67% of the athletes skip meals sometimes and 71% of these skipped breakfast, while the remaining 29% skipped lunch. The results also showed that 19% of the athletes skipped breakfast three times a week and the remaining 14% never skipped meals.
The total caloric intake is also essential in the energy supply for athletes which in turn greatly reflects performance. Too little an intake may result in fatigue, poor performance, lowered body weight and lowered body fat composition. It appears that the (ENTER YOUR SCHOOL) athletes met 102% of their RDA, which falls into the ideal range. At a 95% level of confidence it appears that the total caloric intake of the RDA lies 95% and 100%. It is recommended that athletes consume between 3,000 and 5,000 calories a day. This number is a little lower for female athletes. There was a little variance between that of the (ENTER YOUR SCHOOL) male athlete s mean caloric intake which was 3,344, and the LCSC female athlete s mean caloric intake which was 2467. This is not unusual and in many cases males require a greater number of calories to account for their larger body mass.
Overall, I feel that my Research Project was fairly successful. There are some areas that were a little disappointing. One of these include the response to the surveys. I only received 42% back and I think that there are some reasons for this. One of these include the fact that many of the athletes were travelling, they had either been on the road or they were about to travel. A different reason is that for many of the athletes time is a big factor, especially while in season it may be very hectic for them. I also feel that some of the athletes felt that their coach may see the survey. This seemed to be of concern to some of the athletes. For such a reason some did not return them and some of those that did it made me a little unsure as to how accurate the nutritional information actually was. This seems to be particularly relevant in the area of alcohol consumption. A different reason may also have been because the survey was a little long. Other athletes may have felt that their daily intake was personal and may not feel comfortable having it as part of a Research Project. Some things that I would change if I was to repeat this project is that I would make the survey a little shorter. I would either reduce the number of days to 3 for the Nutritional analysis or I would not include that section at all. I would also make more certain that the athletes were aware that the surveys were strictly confidential.
There were some other difficulties that I came across while making calculations. These were in determining the level of confidence. For most of the areas of nutrition I was able to make statements at a 95% level of confidence. However, there were some areas that held a high variance if determined at this level. In such cases I lowered the level of confidence to decrease the variance. This was the case for RDA percentage for Vitamin B6. There was one negative aspect that accompanied this, which was it increased the probability of error from .05 to 0.1.
After carrying out a nutritional analysis on 14% of the student athlete population (ENTER YOUR SCHOOL), it is clear that there are areas of nutrition that can be improved. This is particularly clear in areas such as carbohydrates where its intake fell below the RDA. There was also a low intake of calcium, vitamin B6 and potassium. Other areas studied that may decrease performance included the intake of alcohol and caffeine. There was also a high percentage of athletes that skipped meals along with a regular intake of fast food. However, there were some areas that contradicted my hypothesis and this was in the percentage of protein which fell closely into the ideal range, yet there was an increased intake over the RDA for protein. This was similar with fat intake, although it also tied in closely with the ideal percentage there was an increase of saturated fat over the RDA. After carrying out this research project I feel that there are some changes that I would make if I was to repeat it, yet overall I feel that it ran fairly successfully. After studying this in great depth it seems to be particularly clear that many of the athletes that attend Lewis-Clark State College, do not adjust their diets in such a way that they can enhance their performance which can come about through proper nutrition.
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Hoeger, Sharon A. & Hoeger, Werner W.K. Principles and Labs for Physical Fitness. Englewood, Colorado: Morton Publishing Company, 1997.
Sizer, Frances & Whitney, Eleanor. Nutrition Concepts and Controversies. Canada: Wadsworth Publishing Company, 1997.
Vincent, William J. Statistics in Kinesiology. Champaign, IL: Human Kinetics, 1995.
Williams, Sue Rodwell. Basic Nutrition and Diet Therapy. St Louis, Missouri: Mosby – Year Book Inc, 1995.