Introduction
Wen highly trained, motivated and talented athletes meet for competition there is a very small margin of defeat and victory. When everything else is on a level platform, nutrition becomes the determinant between losing and winning. Many athletes ignore key dietary issues and only focus on supplementing their diet with vitamins, minerals and proteins. Any professional athlete knows the value of nutritional support when it comes to performance(Perez-Schindler, Hamilton, Moore, Baar, & Philp, 2015). There is a lot that is involved including energy requirements, body mass, the type of foods, the sport involved and much more. All these factors work together to produce optimal results. This paper will focus on certain aspects of the nutritional support for athletes including the athlete’s physiology, their nutritional requirements and the factors that affect the nutrition of athletes.
Exercise Physiology
This subject is concerned on how the body’s adaptation to the demands brought about by physical activity. The body is always in constant adaptation. However, sports heightens the ability of the body to be more adaptive to competition, training, and other circumstances. Experts say that sports cause the most profound stress to the body a good example is when a running marathon is capable of increasing one's metabolic rate many times compared to when one is experiencing a fever.
Physiology brought about by exercises tends to affect every organ and process in the body, but it primarily centers upon significant physical systems that directly impacts the athlete’s performance (Armstrong & McManus, 2010). Such systems include the musculoskeletal system, body composition, the thermoregulatory system, the cardiorespiratory system and the cardiovascular system. It is these systems that tend to have the greatest impact on the athletes’ ability to improve or maintain their level of performance in sport.
In respect to the cardiovascular system, exercise reduces the amount of the body’s low-density lipoproteins hence reducing the risk of conditions such as atherosclerosis, which causes the narrowing of blood vessels. Exercise makes the blood vessels of the athletes more elastic hence allowing a greater blood flow throughout the entire body. Exercise also makes the heart muscles grow stronger with time since it gets adapted to working harder with every exercise. Consequently, the resting pulse reduces as the heart does not have to pump blood as fast so as to achieve similar effects when the body is at rest.
As for the cardiorespiratory system, exercise improves the body’s ability to take up oxygen from inhaled air to the lungs. It also loads and transports the oxygen more efficiently (Armstrong & McManus, 2010). As the efficiency of the movement of blood through the cardiovascular system is being improved through the cardiovascular system so does the amount of oxygen being transported from the respiratory system.
Exercises enhance the thermoregulatory system by enhancing the process of accimilisation. In the case where the athlete is not accustomed to warm weather, exercise allows for easy adaptation through a reduced heart rate (increase the efficiency of the heart), expanding the blood volume (corresponds to a greater blood capacity), faster conversion of sodium promoting more effective hydration (through the osmoregulatory system which optimally balances the proportions of water to sodium). Lastly, through increasing blood flow to the skin surface (creates a cooling effect as blood is directed towards the cooler skin surfaces).
Exercise also causes faster muscle development in conjunction with a reduction in body fat as a result of the differences in energy output and intake. Flexibility and stretching exercises increase the range of motions in all joints subjected to stresses. Consequently allowing for more stable, more powerful and faster movement (Armstrong & McManus, 2010). With an improved range of motion, the joint is less likely to become injured and overstressed. The bones also undergo structural changes to have more bone density as a result of resistance through weight training and running.
Athletes Nutritional Requirements
Proteins
Ingested protein is normally broken down into its constituent amino acids that which help in everything from repairing body tissues to digesting food. Compared to carbohydrates that provide the body’s fuel while still in action: proteins play a vital role in post-workout recovery. Proteins are needed in the repairmen of exercise-induced damage. It aids in the replenishment of depleted energy stores, in preparation for the next bout of activity (Tarnopolsky, Gibala, Jeukendrup, & Phillips, 2005). Proteins can be plant-based or animal-based, all of which can form part of a balanced diet. Some of the plant-based sources of protein include soy products, nuts, peas and beans. Foods rich in animal-based proteins include dairy products, eggs, seafood, poultry, and meat. For best results, the athlete needs to maintain a carbohydrate to protein ratio of about 4:1 or 3:1.
Fat
The hardworking muscles of athletes need the caloric energy that comes from fat. It is worth noting that fat contains nine calories per gram which are quite higher compared to the four calories per gram offered by proteins and carbohydrates). The calorie density of fat coupled with the body’s fat reserves makes it the largest reserve of energy. While the calories offered by fat are not readily accessible for athletes performing intense and quick efforts like weight lifting and sprinting they are essential for endurance and low-intensity exercise including long-distance running and cycling.
Carbohydrates
The athlete’s body requires a lot of oxygen for most of the endurance events. It is this reason that gets breathing quicker and shallowly during an exercise. Carbohydrates are considered the most efficient source of energy due to their minimal oxygen requirements. Less oxygen is used for every kilocalorie produced by carbohydrate when compared to proteins or fats. Therefore making it a significant food choice for most athletes. An example of meals rich in carbohydrates includes; potatoes, bananas, parsnips, carrots, brown rice, grilled chicken, dried fruits such as apricots and resins.
Vitamin D and Calcium
Reduced levels of these in the body increases the risk of stress fractures due to low bone mineral density. Calcium plays an important role in normal blood clotting, nerve conduction, regulation of muscle contraction, and growth, repair and maintenance of bone tissue. On the other hand, vitamin D is essential for the maintenance and development of the skeletal and nervous system (Perez-Schindler et al., 2015). It also plays a key role in bone health as the body needs it for the absorption of calcium. Foods rich in calcium include cheese, yogurt, and milk and to a much lesser extent dried beans and green leafy vegetables such as kales and spinach.
Factors that Affect Nutrition in Athletes
Every athlete is unique. They have different nutrient and energy requirements based on their body size, sporting activity, and training load. Also, they also have varying individual biochemical and physiological characteristics that determine their nutrient needs. It is, therefore, paramount for each athlete to determine key their personal nutritional goals, about energy requirements, fats, carbohydrates and vitamins and minerals that are vital for performance and health. Athletes also make different food choices depending on lifestyle and cultural issues, but mostly on personal preference and taste.
Any form of exercise including those carried out by the athletes increase the rate at which the body uses its energy. Unless one reduces the energy expenditure, they will have to compensate for the energy lost through increasing the energy intake accordingly. Energy demands of the athletes vary depending on a lot of factors such as the training load and the body mass. Taking part in hard physical exercises while on an energy-restricted diet can have debilitating effects on the athlete including an increase in the production of catecholamine and cortisol which compromises the immune system and also an increase in the rate of protein catabolism.
In athletics, it is advantageous to have a low body mass (low body fat content), the athletes usually cut down on the foods that they consume for prolonged periods of time (Armstrong & McManus, 2010). There is a very big difference between sports that require the performers to have a low body fat with a high energy turnover, for example, marathon running and those sports where the energy requirements are low including horse racing and gymnastics.
The type of sport affects to a very great extent the dietary intake of an athlete. Athletes engaging in sports that require quick and intense efforts like weight lifting and sprinting require more carbohydrates than fats. This type of sports requires a large amount of energy within a very short period. Carbohydrates provide a ready source of energy for such athletes. Those engaging low intensity and endurance sports for example long-distance running and cycling, need higher amounts of fat in their diet. Fat is readily stored in the muscle fibers which gets progressively broken down during endurance and lower intensity exercises providing the much-needed energy for such athletes.
The amount of training done by the athlete is also influential in determining his or her dietary intake. Athletes involved in tough training sessions like those in weightlifting require more a high amount of protein which is crucial in the repairment of tissues. During the training sessions, a lot of energy is lost, and a lot of physical strain is placed on the body tissues especially the muscles (Perez-Schindler et al., 2015). The strain involved during training may damage the muscle tissues, tendons, and ligaments. Dietary protein will help in the replacement and repairment of these tissues.
Conclusion and Recommendations
It is common knowledge that dehydration that might result from the inadequate fluid intake or due to losses such as sweating and urination can have debilitating effects on the performance of the athletes. However, most people are unaware that pre-existing fluid deficits are capable of reducing the athlete’s capacity when performing high-intensity exercises. Apart from the usual route of body water loss, there are other ways the athlete can lose water for example through lungs especially in air conditioned environments and in the case of infectious diarrhea. With this in mind, the athlete is required to maintain body water content at levels close to euhydration, through the constant intake of fluids with every meal. Preferably 16 ounces of water every two hours. Also by sipping water before, during and after the exercise. Experts suggest that it is better for the athlete to drink even when they are not thirsty so as to keep them constantly hydrated.
It is recommended that the athletes achieve the desired body weight for competitive purposes. This is done cautiously otherwise, it might cause more harm than good. Losing weight too quickly, keeping the body weight to low or barring weight gain in an unnatural way may end up having negative health consequences for the athlete. It is vital for the athlete to set realistic and achievable body weight gain goals Young athletes who are determined to lose weight should work in close contact with a registered dietician rather than experimenting with diets on their own. This may lead to poor eating habits with excessive and inadequate intake of certain nutrients. By taking to the dietician, they will be able to establish the right diet for their gender, age, sport and amount of training.
References
Armstrong, N., & McManus, A. M. (2010). Physiology of elite young male athletes. In The Elite Young Athlete (Vol. 56, pp. 1–22).
Perez-Schindler, J., Hamilton, D. L., Moore, D. R., Baar, K., & Philp, A. (2015). Nutritional strategies to support concurrent training. European Journal of Sport Science, 15(1), 41–52.
Tarnopolsky, M., Gibala, M., Jeukendrup, A., & Phillips, S. (2005). Nutritional needs of elite endurance athletes. Part I: Carbohydrate and fluid requirements. European Journal of Sport Science, 5(1), 3–14.
