Nutrients

Carbohydrates

Endurance is fuelled by carbohydrates, primarily. Athletes rely on this to be the predominant source of ATP when it is needed for high intensity exercise. The cells can break down simple and complex carbohydrates much more quickly than fats. The need to create ATP and a very high rate drives the need for a ready supply of its most efficient building blocks. Even when the system is devoid of oxygen, carbohydrates can be used to construct anaerobic ATP, which also produces lactic acid.
Carbohydrates are recommended to make up to around 65 to70 percent of the total calories consumed. For example, if 2000 kilocalories are needed, per day, to maintain body weight, 1400 kilocalories (or 350 grams) of carbohydrates should be eaten per day.
Before any carbohydrates are completely digested and made available to the muscle, they are all converted to a simple sugar called glucose. Glucose is called a simple sugar because it is not broken down into anything simpler before the body can use it. This building block is the common starting point for carbohydrate metabolism and it is what active muscles primarily use to make ATP.
Even though glucose is the ending point for all carbohydrates that enter the body, they are not all nutritionally equal, since the body is only able to create glucose and therefore ATP at certain rates for each substance. Simple carbohydrates are made available to the muscles much more quickly than complex carbohydrates, but the production of glucose and ATP can be far too quick and end up unused by long distance runners, whose goal is to pace themselves.
Vegetables, cereal, rice, paste and grain products usually provide a much higher level of vitamins and minerals than simple carbohydrates (such as candies, pastries and jam). It is, recommended, therefore, by most nutrition experts that carbohydrates should be obtained from complex sources. The most effective nutritional benefit for runners is a diet based on complex carbohydrates. The exception to this is fruit. Most fruits contain fructose, which is a simple sugar, but also contain good amount of vitamins and minerals.
• Good sources of carbohydrates are pasta, rice, potato, noodles, bread, pancakes, cereal, jam, honey and bananas.
• Poor sources of carbohydrates are pizza, cakes, lasagne, fries, donuts, croissants, beer and ice cream
Most glucose is stored as glycogen which when it is not in use. Glycogen is can quickly be converted into ATP within the muscle whenever it is needed. Fat can be stored far more quickly than carbohydrates, and in much larger amounts. About 2000 kilocalories would be all that was available if all the carbohydrate depots in the body were filled with glycogen. However, only approximately 75 percent of it is available to the athlete for ATP production. This amount allows an average athlete to run half of a marathon (up) before all of the available energy has depleted and fats become major supplier. In addition, the brain and nervous system require certain level of glucose in the blood (commonly called blood sugar) in order to maintain normal function. Low blood sugar occurs can result in light-headed feelings and tiredness. The importance of restocking carbohydrate stores on a regular basis and while training is apparent when the effects of neglecting this principle are clear.

Fats

Fats are the other primary source that makes ATP but carbohydrates are much more efficient and produce more ATP over any given time period. Fats, however, should always be included in any diet, even though it is popularly accepted that fats are universally bad. Fat serve to stabilize body temperature and even balance the level of sugars within the blood. When oxygen is readily available, light exercise can stimulate the body to use more fats and fewer carbohydrates, but when the intensity of the workout increases, the body will switch to carbohydrates as a more efficient source of ATP fuel.
It is recommended that fats should make up around 20 percent of the total calories consumed. For example, if 2000 kilocalories per day are needed to maintain body weight, only 400 kilocalories (Which are 45 Grams) of fats should be eaten per day.
It is also important to consume the right type of fat. Vegetables and grain contain unsaturated fats, which are better than the saturated fats found primarily in animal products such as beef and in cream, cheese and butter.

Protein

The most important purpose of protein is to replenish tissues and help the muscles to recover from whatever damage is done by lactic acid build-up. Unlike Carbohydrates and Fats, protein is not very good at producing ATP for muscular activity.
Ten to Fifteen percent of the total caloric consumption should be protein-rich items. According to this recommendation, about 300 kilocalories , or 75 grams, of protein should be eaten each day on a 2000 kilocalorie diet.
Animal sources, such as eggs and dairy products, contain most of the essential amino acids that the body requires and are usually referred to as complete proteins. Vegetable sources can sometimes be devoid of some of the essential amino acids. Sources of protein should also be carefully examined to ensure that they do not have an excessively high fat content.

Vitamins and Minerals
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The nutritional cycle includes far more than energy-producing substances, and the best possible body function relies on the inclusion of vitamins and minerals.

• Vitamins are dense organic composites that catalyse and drive most metabolic functions. Most vitamins should be eaten rather than taken from pills or supplements. Large doses of vitamins can be harmful, as the reactions and chemistry in which they are involved could be driven out of balance by an overabundant presence.
•Other substances that are as important as vitamins are minerals. These naturally occurring inorganic elements also play a part in the physiological inner workings of the body.

The most vitamins and minerals can actually be found in raw or unprocessed foods. The content of these important components is dwindled away by each level of processing a food item endures, with the exception of foods that are prepared with vitamin supplements added. Complex carbohydrate foods are the very best source of vitamins and minerals, since they are usually not processed very much, and do not contain a great deal of fats or other substances that break down the energy production process in the body. Adults, generally, lack an acceptable level of vitamin and mineral intake. Multivitamin supplements that offer the recommended daily amount of the necessary vitamins can be a good substitute, but altering food habits to include more vitamin-rich dishes will produce better results at a lower cost.

Antioxidants – Some of the nutrients that are essential to detoxification systems in the body are found only in antioxidants. Potentially harmful free radicals ( or substances that do not belong in the body) are removed this way, and athletes who exercise daily need more of these antioxidants to prevent a build up of harmful substances in the muscles.
Calcium – Bones and their strength depend on calcium intake at adequate levels. The chances of injury can be drastically increased by a lack thereof, and stress fractures will seriously hamper any serious runner’s training schedule. Particularly female athletes have a very hard time maintaining a sufficient calcium level. Dairy products contain some of the most readily available recommended daily supplies of calcium and should be a part of any trainee’s diet at roughly 4500 milligrams of calcium each day.
Iron – The blood cells in the human body rely on iron to transport oxygen from place to place within the blood stream. This vital oxygen cycle cannot be left out of the athlete’s mind when involved in endurance sports like marathon running. When trying to decrease weight, many athletes tend to consume less meat and therefore lose their iron levels. Meat, bread, cereal and a vegetable called spinach can all be high-end sources of iron, and it is recommended that most athletes consume roughly ten milligrams per day.

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