Nutrition is the reasonable food needed by humans to repair old tissues, proliferate new tissues, produce energy and maintain physiological activities. Substances in food that can be absorbed and utilized by the human body are called nutrients. Protein, fat, carbohydrates, vitamins, minerals and water are the six major nutrients needed by the human body. The first three produce energy after metabolism in the body, so they are also called energy-producing nutrients.
(1) Protein If the human body is regarded as a building, then protein is the building material that constitutes this building. Important components of the human body: blood, muscles, nerves, skin, hair, etc. are all made of protein; protein also participates in the renewal and repair of tissues; regulates the physiological activities of the human body and enhances resistance; protein also produces energy, supporting the growth and development of children. It provides energy, so it is one of the energy-producing nutrients
(2) Fat is an important component of human tissue cells. It supplies heat after being absorbed by the human body. It is the 2nd energy source of the same amount of protein or carbohydrates. times; fat is an important reserve form of energy supply in the human body; fat is also conducive to the absorption of fat-soluble vitamins; it maintains normal physiological functions of the human body; body surface fat can insulate and maintain heat, reduce body heat loss, and support and protect various Organs and joints are not damaged.
(3) Carbohydrates are the main source of calories for the human body, participate in many life activities, and are components of cell membranes and many tissues; maintain normal nerve function; promote the metabolism of fat and protein in the body .
(4) Vitamins are a class of compounds necessary to maintain normal physiological functions of the human body. They do not provide energy and are not structural components of the body, but they are absolutely indispensable in the diet. For example, if a certain vitamin is lacking or insufficient for a long time , which can cause metabolic disorders and pathological conditions leading to vitamin deficiency.
(5) Minerals are another type of nutrients that are indispensable to human beings. They include elements needed by the human body, such as calcium, phosphorus, iron, zinc, copper, etc. Minerals are important raw materials that make up human tissues and help regulate acid-base balance, muscle contraction, nerve responses, etc. in the body.
(6) Water is an important condition for the survival of humans and animals (including all living things). Water can transport various substances necessary for life and eliminate unnecessary metabolites in the body; promote all chemical reactions in the body; regulate body temperature by dissipating a large amount of heat through unconscious water evaporation and sweat secretion; synovial fluid in joints, respiratory tract and gastrointestinal tract Mucus in the tract has a good lubricating effect. Tears can prevent dry eyes, and saliva is helpful for moistening the pharynx and swallowing food.
The six major nutrients needed by the human body are: sugar, fat, protein, water, inorganic salts and vitamins. Among them, sugar, protein and fat are substances that supply energy to the human body. The six major nutrients mainly come from eight major food categories: cereals, eggs, milk, roots and tubers, meat, fish, shrimp and shellfish, beans and dried fruits, vegetables and fruits.
1. Protein is an essential substance for the growth and development of children and adolescents. Lean meat contains the most protein. The general intake is 1.5 to 2 grams per kilogram of body weight per day, but when children participate in physical exercise, protein requirements increase, and protein intake is generally required to reach 2 to 3 grams per kilogram of body weight per day. Because the thickening of muscle fibers and the increase in muscle strength must rely on the increase in protein content in the muscles, and it is best to use animal protein. But be aware that gains in muscle size and strength are primarily a result of training, not eating.
2. Sugar is a necessary substance to protect the liver and maintain a constant body temperature. Fatty sugars provide 70% of calories to the human body. Generally, 250 to 750 grams of staple food per day can meet the body's caloric needs. There are certain sugar reserves in various tissues of the body. Therefore, generally children do not need to supplement sugar when participating in general sports activities. Only when children participate in heavy exercise activities or long-term endurance activities, the amount of staple food should be appropriately increased. Ingestion. Because exercise consumes a lot of calories, if the energy supply is insufficient for a long time, it will lead to body weight loss and weakened body resistance.
3. Fat is the substance with the highest calorie content in the human body. Fat has four main functions: maintaining normal weight, protecting internal organs and joints, moisturizing the skin and providing energy. Generally, the human body's daily requirement of fat accounts for 15% to 30% of the total calories in food. Generally, people with normal activities can meet their physiological needs by consuming about 25 grams of fat per day. If they participate in activities for a long time, this can be increased to 30 to 36 grams per day. But be aware that if the amount of activity is insufficient, the extra calories consumed will be converted into body fat, making the child gain weight instead of growing strong muscles.
4. Vitamins are essential organic compounds for children’s growth, development and physiological functions. Lack of vitamins can lead to metabolic process disorders, physiological dysfunction, weakened immunity, and various diseases. Generally, natural foods contain various nutrients we need in appropriate proportions. Therefore, children can get sufficient vitamins from a reasonable diet. Only when caloric nutrition cannot meet the needs of sustained, high-intensity, large-volume exercise, or when the supply of vegetables and fruits is insufficient, additional vitamin supplements are needed. It should be noted that excessive intake of vitamins can lead to adverse consequences just like vitamin deficiency.
5. Inorganic salts are also called minerals and trace elements, and they are also necessary substances in human metabolism. Children and teenagers have a high demand for calcium, phosphorus, and iron. During exercise, due to a large amount of perspiration, salt is lost with sweat. It must be replenished in time to prevent muscle spasms and help relieve physical fatigue. Inorganic salts can be supplemented through sports drinks.
6. Water is the "source of life". Children who participate in sports should be proactive about hydrating. For example, 15 to 20 minutes before exercise, add 400 to 700 ml of water, which can be divided into several drinks. During exercise, add 100 to 300 ml of water every 15 to 30 minutes, preferably a sports drink. After exercise, you should also replenish water, but it is not advisable to concentrate on "binge drinking". You should replenish water in small amounts and multiple times. Children who participate in sports can only have good physical fitness and health by maintaining good water nutrition.