There are some quick facts that athletes needs to note regarding their nutrition. One is that they achieve their peak performance through eating a wide range of foods and training, Much is gained from the stored carbohydrate’s amount in the athlete’s body, Depending on the duration taken by the exercise or the athlete’s condition, there reaches a time when fat is needed for provision of fuel, the protein need of an athlete can be increased by the kind of exercises that are undertaken, and water is very essential for athletes based on the fact that dehydration can lead to fatigue and muscle cramps. As a result of the stated facts; it is clear that for an athlete to expel in athletics, one should have perfect genes, good body conditioning and training and a reasonable diet. To maintain a peak performance, it is therefore necessary that an athlete ensures that they have an optimal diet. Lack of correct information regarding nutrition can be harmful towards the course of achieving the goals of the athlete (Rusell, 2005).
During the early stages of an exercise that is temperate, about 50% of the energy taken by the body comes from carbohydrates. The energy produced by carbohydrates for every unit of oxygen that has been consumed is higher than that produced from fats. Based on the fact that the supply of oxygen during the long duration activities, it is advisable that the athlete consumes the diet with the least requirement of oxygen for every kilocalorie that has been produced. After being ingested, carbohydrates are partially digested in the mouth as a result of the action of amylase enzyme that is found in saliva. The digestion then continues in the stomach but is slowed down by the digestive acids that are released into the stomach. Pancreatic amylase furthers the breakdown in the duodenum breaking the carbohydrates further to sucrose, lactose and maltose. Sucrase, lactase and maltase acts further on the food as it is carried into the intestines breaking it into very small bits that are converted into glucose before being absorbed into the bloodstream. While the athlete is undertaking any activity the energy that is needed appears in the form of ATP and this is stored in small quantities that be utilized by the body in a few seconds and hence the need to replace it every other time. As mentioned earlier, the carbohydrates that have been consumed produces glucose to the body. The glucose is stored as glycogen for production of energy in later stages (Fink et al, 2008).
Sports people have different needs of energy but this dependent on the body size, composition and the kind of physical training they are undergoing. A person with a small body needs about 1500 calories for maintenance of the body weight. In this case, Zoe weighs 135 and a height of 5’8 and this means she has a large muscle mass and needs more calories, about 4000, to maintain her body weight. The fuel that is consumed by the body of an athlete during training is dependent on their sex, the duration or intensity of their exercise and the nutritional status of the athlete. The central part of the nutritional plan is based on the three major macronutrients for every athlete and these are proteins, carbohydrates and fats. The average intake of nutrients is 56-58 carbohydrate’s energy, 11-15% energy from proteins and 24-30 % energy from fat. However, these ranges from one athlete to the other depending on a number of varying factors from individual to the other as mentioned before (Rusell, 2005).
The utilization of carbohydrates increases as the work intensity increases. During the process of digestion of the carbohydrates, they are broken down into glucose and this is stored as glycogen in the body muscles. When the athlete is actively participating in the the sport or during the routine exercises, the energy is produced through conversion of the glycogen back into glucose (Collins, 2007). Only a limited quantity carbohydrate is stored by the body in the liver and the muscles. Provided the event does not take more than one and a half hours, the glycogen in the muscle is sufficient to supply the energy that is needed for the activity. For the activities that involve hard work and for more than one and a half hours, a diet with high concentration of carbohydrates that was eaten a few days before undertaking the activity permits the space storage of glycogen to get filled. This means that whenever Zoe is doing the running or during the soccer matches, she can benefit a lot from taking a diet prior to competition and the diet is supposed to contain about 70 percent carbohydrates’ calories (Collins, 2007). It has been proven that athletes or soccer players who are on a high-carbohydrate diet can be able to exercise for long hours as compared to those who have not taken such a meal. However, it is not advisable that Zoe gets used to the high-carbohydrate diet based on the fact that the body may get used to obtaining fuel from carbohydrates instead of incorporating the fatty acids that come from fats (Fink et al, 2008).
One thing that Zoe needs to know is that to be able to sustain her performance in relation to the feeding habits, there is an appropriate time that one needs to feed especially prior to a game or a training session. The absorption of food needs to have been accomplished and the glycogen stores replenished fully before one starts an active exercise. After the training session or a competition, Zoe needs to know that her glycogen stores gets depleted and she needs to put into consideration the time taken for the carbohydrates to be changed into blood glucose that is then stored in the muscles (Rusell, 2005). This is very important especially if she is to undertake some games in a series. This is where the Glysemic Index (GI) of food comes in. the foods whose GI is high take about 1 to 2 hours for absorption to take place while those with low GI take about 3 to 4 hours. As a result, consuming of carbohydrates whose GI is high in two hours time after undertaking an activity will assist Zoe in replenishing the glycogen stores and this will lead to a fast recovery time. These stores are known to take about half a day during rest or sleep and this means that she should consider taking breakfast always. Eating some snacks will play a part in maximizing the glycogen stores, minimizing storage of fat and stabilizing blood glucose as well as levels of insulin (Fink et al, 2008).
Fats and oils assist the body of the sports people with the provision of fuel for the body. Half of the energy that is spent on a moderate exercise is derived from the metabolism of fatty acids that are free (Fink et al, 2008). When the individual undertakes an activity that will take more than an hour, the body can mostly use fats for the provision of energy and based on the fact that she is a trained athlete, her fat utilization will be higher than that of a person that is not trained. Based on the fact that Zoe is heavy and may be considering loosing some weigh, she can be tempted to practice fat restriction and this can affect her performance based on the fact that the fat intake should never be below 15% of the total energy intake and if this is not checked, the performance of Zoe may be affected immensely (Rusell, 2005).
In addition to carbohydrates and fats, proteins are also responsible for the provision of energy for the athlete’s body. In case there is extra protein that has been consumed, it is stored in the body as fat. What Zoe needs to know is that, with the kind of kilograms that she weighs, she does not need to add weight any longer and if anything, she should be thinking of how to shed some of the weight that she has. As a result, she should ensure that she only takes enough proteins to avoid some fat storage in the body in form of the excess proteins. The protein intake of Zoe should range between 10% and 12% of the total calories to ensure that her intake fits what her body requires and that there is no excess to avoid harm. This translates to about 1.2-1.7 grams of protein for every kilogram of her body weight (Fink et al, 2008).
Based on the fact that Zoe exercises vigorous almost everyday except on Sundays, her feeding habits needs to incorporate carbs amounts that range from moderate to elevated amounts. In her feeding programmes, she needs to incorporate about 6gm of carbohydrates for every Kilogram of her body weight and considering that she is 135Kg, this means that she needs about 810grams of carbohydrates each day. In short the carbohydrates intake should be about 45% of her calories or carbs about 65% of the calories being used. This will assist her in avoiding chronic fatigue as well as overloading her liver and muscles with glycogen. The protein intake for Zoe is 1.1 to 1.4 grams protein for every kilogram of her body weight (Fink et al, 2008). For the protein to be used to maintain the tissues of the muscles and not as a fuel source there should be enough carbohydrates as mentioned earlier. In regard to the fats and oils intake, Zoe as an athlete who exercises regularly almost everyday can take up to 30% of what she consumes daily. However, having in mind that Zoe is a huge person with an excessive body weight; she needs to maintain the percentage of oils and fats at a mere minimum. It should be noted that the fats should have very little or no amounts of trans or saturated fats and rich in unsaturated fats (Collins, 2007).
Based on the fact that carbohydrates in its digestive forms undergoes a transformation into glucose, the glucose has to provide the body tissues and cells in form of ATP (adenosine triphosphate) and in this case the metabolism of glucose is carried out in three major stages; glycolysis, Krebs Cycle, and oxidative phosphorylation. During the athletic activity, the level of hormones shifts and this homeostasis disruption makes some alteration to the carbohydrate’s glucose metabolism as well as other molecules that bears some energy (Collins, 2007).
Glycolysis is the first step of glucose breakdown. When glucose enters the cell’s cytosol or the fluid of the cell, it is changed into pyruvate 2 or 3 carbon molecules through a number of reactions (ten) which are catalyzed by different enzymes. For every molecule of glucose, two ATP are generated and since ADP is changed to ATP throughout the breakdown carried out on the substrate glucose, a process that is referred to as phosphorylation of substrate-level (Haugen, 2010). During glycolysis, the most precious enzyme is the phosphofructokinase or PFK that is responsible for the catalysis of the 3rd reaction in the entire sequence. The reaction is favored by physiologic conditions and as a result, it is referred to as the ‘committed step’. This implies that PFK appears as the one responsible for controlling the metabolism of glucose and in actual sense, this is the reality. When the cell has much energy or ATP, PFK gets inhibited and the glucose breakdown for energy production reduces. This kind of regulation where the PFK controls the degradation of glucose to fit the energy requirements is a common issue in biochemistry (Fink et al, 2008).
The next stage is the krebs cycle that is said to begin pyruvate that is structured in the cell cytoplasm during glycolysis is moved to the mitochondria whose majority energy that is contained in the glucose gets extracted. The mitochondria facilitate the conversion of pyruvate to acetyl CoA through an enzyme pyruvate carboxlase. This process goes through a series of steps but the main purpose of Krebs Cycle is to ensure that there is provision of high-energy electrons that appear in form of NADH and FADH2 and these are carried forward to the transport chain of the electron (Fink et al, 2008).
During the last stage which is known as the oxidative phosphorylation. High energy electrons that are held by both FADH2 and NADH are carried on to an enzyme complex series in the membrane of the mitochondria. In an effort to reap the energy contained in both NADH and FADH2 and changes it to ATP: NADH-Q reductase, cytochrome oxidase and cytochrome reductase. Generally, two ATP molecules are generated from the Kreb Cylcle reactions and electron transport chain then produces around 26-30 ATP. In short, the glucose oxidation as a result of reduction of FADH and NAD+ is joint to the process of phosphorylation of ADP with the aim of producing ADP. This is the reason why this process is referred to as the oxidative phosphorylation (Fink et al, 2008).
The processes of anabolic lead to the production of polysaccharides, nucleic acids, lipids, peptides and proteins and this is a collection of different living things materials. The opposite of anabolism is catabolism and this produces molecules that are smaller and are utilized by the cell to form larger molecules. ATP that is rich in energy is the main supplier of energy behind the process of anabolism and this energy is released when the bond breaks and ATP changes to ADP. During the reactions of anabolic, the ATP phosphate bond is transformed into a substrate so as to energize it to prepare it for the subsequent molecule utilization as a raw material for the larger molecule production. Whenever the cell is in need of producing certain proteins, the production is carried only for the specific amino acids that are required for the synthesis of the proteins (Fink et al, 2008). Furthermore there are those amino acids that are applied by the cell to produce glucose that emerges in the blood or a carbohydrate that is kept in the liver and is known as glycogen. As a result, the catabolism products of amino acid do not have accumulations but instead are fed on the anabolic pathways of the synthesis of carbohydrates. The rate of anabolic reactions is regulated by the cell through allosteric enzymes means (Rusell, 2005).