Training Marathon
Nutrients
Carbohydrates
The most important energy nutrient for endurance athletes is carbohydrates. Carbohydrates become the predominant food source from which ATP is made when you exercise at moderate to high intensities. Compared to fat, carbohydrates takes less time to make ATP, and more of it can be made over any given time period. The faster you exercise, the more fuel (ATP) is needed therefore the faster is the pace, the greater the need to have carbohydrates available to the muscle. Another reason carbohydrates is the preferred fuel by the body when exercising at higher intensities is that carbohydrates can be used to make ATP both aerobically and anaerobically, when the oxygen supply is not completely adequate.
It is recommended that carbohydrates should make up to around 65-70% of total calories consumed. For example, if you need 2000 kilocalories per day to maintain body weight, you should eat 1400 kilocalories (Which are 350 Grams) of carbohydrates per day.
By the time any type of carbohydrates are completely digested and made available to the muscle, they are all converted to glucose. Glucose is the common starting point for carbohydrate metabolism. Whatever you eat wind up as glucose and it is what active muscles primarily use to make ATP. Glucose is called a simple sugar meaning that it is not broken down into anything simpler before the body can use it.
Although all carbohydrates wind up as glucose, not all carbohydrates are nutritionally equal for they are digested and becomes available to the body at different rates. In general, simple sugars are digested more quickly and are made available to the muscles rapidly compared to most complex carbohydrates. However, because complex carbohydrates are digested less rapidly their energy availability is spread out longer which can be an advantage for long distance training and racing.
In addition, complex carbohydrates (Vegetables, cereal, rice, paste and grain products) usually provide a much higher level of vitamins and minerals than simple carbohydrates (candies, pastries, Jam, etc) so it is recommended you get most of your carbohydrates from complex sources. Reduce the amount of simple sugars you consume and increase the amount of complex carbohydrates to benefit your running and health. 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: Pasta, Rice, Potato, Noodles, Bread, Pancakes, Cereal, Jam, Honey, Bananas
- Poor Sources of Carbohydrates: :Pizza, Cakes, Lasagne, Fries, Donuts, Croissants, Beer, Ice cream
Most of the glucose are stored as glycogen which is the way the body stores carbohydrates for future use. when you do exercise, the glycogen in the muscle converts back to glucose to produce ATP.
Compared to the ability to store fat, one of the major problems with carbohydrates is that the body cannot store it in huge amounts. If all the carbohydrate depots in the body were maximally filled with glycogen, it would have about 2000 kilocalories available where only around 75% of is available to the athlete to provide ATP (Rest is located in muscles not used in the actual activity). This amount allows an average athlete to run half Marathon (up to 2 hours) before carbohydrates are 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) for normal function. Low blood sugar occurs when the liver runs out of glycogen due to not eating carbohydrates which cause number symptoms such being tired and light-headed.
Both points emphasize the importance of restocking your carbohydrate stores on regular basis & while training more than 1 1/2 hours.
Fats
Fats are the other primary source to make ATP but they are not as efficient as carbohydrates which produce more ATP over a given time period. While it is important to reduce fat intake to avoid health issues, we should include some fat in our diet. fats are essential for normal function of our body, They balance blood sugar levels and help to maintain body temperature for example.
During rest and light exercise when oxygen is readily available, the body produce more ATP from fat than carbohydrate, However when we increase the intensity of exercise and oxygen intake, the body switches to carbohydrates.
It is recommended that fats should make up to around 20% of total calories consumed. For example, if you need 2000 kilocalories per day to maintain body weight, you should eat only 400 kilocalories (Which are 45 Grams) of fats per day.
It is also important to consume the right type of Fat. Unsaturated fat, found mostly in grain products and vegetables, is better than Saturated fats which are found primarily in animal products such as beef and also in the dairy products such as of cream, cheese and butter.
Protein
Protein primary purpose is to repair tissues and help the muscles to recover from damage done while exercising. Unlike Carbohydrates and Fats, its primary purpose is not to produce ATP for muscular contraction.
It is recommended that protein should make up to around 10-15% of total calories consumed. For example, if you need 2000 kilocalories per day to maintain body weight, you should eat only 300 kilocalories (Which are 75 Grams) of protein per day.
Complete protein which comes predominantly from animal sources, eggs and dairy products contains most of the essential amino acids that the body requires. Other types such as vegetable sources usually lack some of the essential amino acids. In addition, always prefer sources of protein which have low fat percentage.
Vitamins and Minerals
For the best possible functioning of the body, vitamins and
minerals, provided from consumption of a extensive variety of foods,
complete the nutritional cycle.
• Vitamins are a dense organic composites that participate in various metabolic functions. Most vitamins should be taken through food.
Taking large doses of vitamins can be harmful as your body only
needs vitamins in small amounts.
• Minerals are naturally occurring inorganic elements which play a part in physiological processes necessary for good health. They are as important as vitamins to function properly.
Raw and unprocessed foods offer additional vitamins and
minerals. In general, the
more processed a food is, the less vitamin and minerals will be
present, unless it is prepared with vitamins and minerals, such as
breakfast cereals. .High-quality sources of vitamins and minerals are normally
established in complicated carbohydrate sources as opposed to simple
carbohydrates (Such as Jam, Sugar, etc).
The majority of us do not obtain
sufficient vitamins and minerals in our diets. If that is your case,
you should consider taking supplements such as Multivitamin that
offers the recommended daily amount (RDA) for a number of the
vitamins and minerals.
Antioxidants - Nutritional antioxidants include a vast range of essential a nutrients that can assist in the detoxification of potentially harmful free radicals. Athletes, who exercise on daily basis need more of these antioxidants than usual, especially vitamins E, C, and A as free radical production is amplified.
Calcium - Calcium is needed for bone formation and bone strength so its critical you have adequate levels, otherwise your increase the chance of injuries concerning bone, like stress fracture. Runners (& particularly female athletes) have a tendency to be at a higher risk for insufficient calcium intake due to the shock of pounding. Therefore, if dairy products are not included in your diet, make sure you use supplements. Specialists believe these RDA’s are too low and that adult’s need between 1200 to 4500 mg of calcium daily.
Iron - Iron is a mineral essential for oxygen transportation, it helps your blood cells carry oxygen needed for energy, Something endurance athletes need more of. Endurance athletes, especially females, are more likely to decrease their caloric consumption in order to uphold a lower body weight. As a result, they do not consume an adequate amount of meat which is where most of us get our iron. Meat (Especially lever) Bread, cereal (Some types) ,Spinach and other whole carbohydrates are high-quality sources of iron. The recommended iron intake for men and post-menopausal women is 10 mg
