1, and the proportion of carbohydrate (sugar) in human body is 1%-2%. The food source that constitutes the classification function lacks excessive adult intake, and the human body needs 7.5g per kilogram of body weight every day.

2. The most important monosaccharide in human body is glucose. Classification of sugar: monosaccharide, disaccharide and polysaccharide.

Monosaccharide (glucose, fructose, galactose): sweet and easy to be absorbed by human body;

Disaccharides (sucrose, maltose and lactose) are decomposed into monosaccharides by digestive enzymes;

Polysaccharides (starch, cellulose) that are not sweet in taste are decomposed into glucose by amylase.

3. Carbohydrate (sugar) The main source of human heat energy: 4 kilocalories per kilogram of carbohydrate. It accounts for 40-50% of the total energy source of human body.

4. Carbohydrate (sugar) constitutes human tissue cells, regulates fat metabolism, glycogen helps the liver to detoxify, and glycoprotein can enhance human immunity.

5, carbohydrate (sugar) intake is too small: people will be afraid of cold, easy to fatigue, functional decline, weight loss, hypoglycemia.

6, excessive intake of carbohydrates (sugar): it will produce hyperglycemia and easily lead to diabetes.

7. Sources of carbohydrates (sugar): pure sugar (brown sugar, white sugar, honey and maltose), cereals (rice, millet, flour and corn), dried beans (soybeans and broad beans), rhizomes (potatoes and taro) and hard fruits (chestnuts and peanuts). ).

8. Carbohydrate (sugar) and exercise: Modern people like to eat monosaccharides, which are easier to absorb. In order to maintain muscle endurance, the intake of sugar can be appropriately increased. But eating too much sugar is easy to be obese, and obese people should control it properly, but it is wrong to completely refuse to eat sugary substances or starch. The absorption process of polysaccharide is complicated and it is not easy to cause obesity.

(2) Fat

1, and the proportion of fat in human body is 10%- 15%. The fat in general food accounts for 20-25% (not more than 30%) of the total energy source of human body, and it needs 1- 1.5g per kilogram of body weight every day.

2. Triglyceride is the main component of fat. Classification: saturated fat and unsaturated fat.

3, saturated fat: too much animal fat (milk, lard, butter, chicken oil), easy to cause arteriosclerosis or heart disease.

4. Unsaturated fats: For example, plant fats (soybeans, peanuts, rapeseed, sesame seeds, corn) contain acid, and excessive intake can also cause sequelae such as obesity.

5. The energy supply of fat unit is the largest, and 9 kilocalories can be generated per kilogram of fat.

6. The function of fat: protect skin and internal organs, keep body temperature, form human tissue cells, promote the dissolution, absorption and utilization of fat-soluble vitamins, and affect tissue function.

7. Insufficient fat intake: it is not conducive to the cell composition in human organs and tissues, and is not conducive to the absorption of fat-soluble vitamins.

8. Excessive fat intake can easily cause diseases such as arteriosclerosis. Hyperlipidemia is closely related to cholesterol. Too much fat can affect endurance and the absorption of protein and iron.

9. Food sources of fat: pure oil (such as soybean oil, peanut oil, lard, tallow, fish oil, vegetable oil, sesame oil and corn oil), meat, egg yolk, hard fruit (such as walnut, peanut and melon seeds) cream, cream oil, etc.

(3) protein

1, the proportion in human body is 15%- 18%. Daily weight requirement per kilogram: 0.8- 1.2g, athletes, etc. : about 2.5g/kg.

2. Amino acid is the basic unit of protein. Classification: complete protein and incomplete protein.

3. Complete protein contains all essential amino acids needed by human body (such as animal meat, 98% of which can be absorbed by human body). Incomplete protein: such as plant protein (80% absorbable).

4. There are 8 kinds of essential amino acids, which cannot be synthesized by human body and need to be obtained from food (12 kinds of non-essential amino acids).

5. protein can supply energy: every kilogram of protein can produce 4 kilocalories of energy.

6. protein constitutes tissue cells, participates in tissue repair, regulates human physiological functions, growth and development, and affects the activities of nerve centers. Control heredity and enhance human resistance.

7. Too little intake of protein: It will cause endocrine disorders, indigestion, weight loss, decreased resistance, fatigue and anemia.

8. Excessive intake of protein: protein cannot be fully absorbed, and the metabolic burden is heavy.

9. Food sources in protein: pure oil (such as soybean oil, peanut oil, lard, tallow, fish oil, vegetable oil, sesame oil and corn oil), meat, egg yolk, hard fruit (such as walnut, peanut and melon seeds) cream, cream oil, etc.

0. protein and exercise: When exercising for a long time, we should pay attention to prevent protein from losing a lot, and the effective method is to increase the supply of carbohydrates appropriately. People who take part in fitness exercises, especially strength exercises, have a high demand for protein, especially in the early stage of practice, to supply enough protein.

(4) minerals

Characteristics of minerals: Minerals account for about 5-6% of human body weight (carbon, hydrogen, oxygen and nitrogen account for 96% of the total). Minerals cannot be synthesized by themselves in the human body and must be provided by food. Although 99% of calcium, 80% of phosphorus and 70% of magnesium in human body are concentrated in bones, bones and teeth, minerals can maintain the acid balance in the body, maintain the osmotic pressure of intercellular fluid, participate in the metabolism of fat, protein and carbohydrates, and maintain the normal function of muscles, nerves and heart.

Minerals and Exercise: Because of the high level of thermal energy metabolism during exercise, the body sweats a lot, which increases the discharge and consumption of calcium, phosphorus, potassium and iron in the body, so practitioners should supplement it in time and in moderation after exercise to maintain the normal metabolic function and physiological needs of the human body.

(5), vitamins

Characteristics of Vitamins: Vitamins, also known as vitamins, contain very little in human body, as long as they are very small, they can maintain the normal growth, reproduction and health of animals. Vitamins must also be metabolized normally through a living organic diet, instead of ordinary carbohydrates, fats, protein or minerals, and absorbed in small amounts to maintain health.

Vitamins have the following characteristics: most vitamins cannot be synthesized by themselves in the human body and must be taken from food. It is not a structural part of the body and does not provide energy. Some vitamins are unstable in nature and are easily destroyed during food processing and cooking. The intake should be appropriate. Without it, the metabolism of substances in the body will be hindered and vitamin deficiency and its diseases will easily occur. Excessive, can cause metabolic disorder in the body, cause vitamin poisoning.

Classification of vitamins:

1, fat-soluble vitamins (soluble in fat): vitamin A, vitamin D, vitamin E and vitamin K.

2. Water-soluble vitamins (soluble in water): vitamin C, vitamin B group, PP, folic acid and biotin.

Vitamin functions: 1) promote growth and reproduction, 2) enhance resistance, 3) improve tissue function, 4) stimulate appetite, 5) keep healthy, prolong life and be full of energy.

Vitamin A: Helps the development of bones and teeth, protects eyesight and skin, enhances human resistance and immunity, and prevents cancer.

Vitamin B 1: constitutes a coenzyme, participates in carbohydrate metabolism, protects the heart, maintains energy metabolism, improves exercise ability, prevents fatigue, maintains the nervous system and increases appetite.

Vitamin B2: Maintain the normal metabolism of substances in the body, contribute to muscle development, and protect eyesight, skin and mouth.

Vitamin B3: It can make people optimistic, treat mental illness, promote nervous system and digestive system, form coenzyme, participate in protein, sugar and fat metabolism, and prevent cardiovascular diseases.

Vitamin B6: Participate in the metabolism, transformation and biosynthesis of amino acids, maintain the normal function of the brain, maintain the normal levels of magnesium and cholesterol in the blood, and prevent anemia, tooth decay and kidney calculi.

Vitamin B 12: Hematopoietic function, preventing fatty liver, and maintaining normal functions of gastrointestinal tract, nervous system and bones.

Vitamin C: Maintain metabolism, enhance immune resistance, prevent allergies, prevent cancer, detoxify, help teeth, develop bones, treat anemia, heal wounds and protect eyesight, beauty beauty (mm must know).

Vitamin D: Promote the absorption and utilization of calcium and phosphorus, help the development of bones and teeth, relax nerves, relieve pain, help the absorption of vitamin A, and prevent osteoporosis and conjunctivitis.

Vitamin E: It has the functions of delaying aging, preventing arteriosclerosis, preventing cardiovascular diseases, improving resistance, preventing and treating cancer, promoting metabolism, increasing endurance, improving physical strength, relieving pain and detoxifying the liver.

Vitamin K: Promote blood coagulation, stop bleeding, increase bone density and promote ossification.

Vitamins and exercise: Aerobic exercise is characterized by high consumption of heat energy and various nutrients, and aerobic oxidation is the main energy metabolism. Therefore, in order to keep the athletes' hemoglobin and respiratory enzymes at a high level, have sufficient sugar reserves in the body, and improve the body's exercise ability, the human body needs to supplement more vitamins such as C, B 1, B2, E and so on.

(6) water

Characteristics of water: Water is the source of life. It is the most abundant in human tissues, accounting for about 60%-70% of human body weight. It plays a very important role in human body and is an important nutrient to maintain normal physiological activities of human body.

Water is widely distributed in human body: 65-75% of muscle weight is water and 25% of fat weight is water. Water is mainly stored in intracellular fluid (about 62% of which is water) and extracellular fluid (for example, more than 90% of blood is water, and there are also body fluids secreted by lymph, saliva, skin and kidney. Water participates in the process of substance metabolism, which contributes to the digestion, absorption, biological oxidation and excretion of substances. Regulate body temperature and keep normal temperature of human body. It is a lubricant for organs, joints and muscles. Maintain gland secretion and enrich body fluids.

Water demand and source: People's demand for water is directly proportional to people's weight and heat energy consumption. The energy consumption per calorie requires 1 ml of water, and 30-40 ml of water per kilogram of body weight. If a 70kg person needs 2 100-2800ml of water. Under normal circumstances, the amount of water in the human body is balanced. A healthy adult needs about 2000-2700 ml of water every day (including drinking water, water in food and water produced by metabolism). If you drink too little water, the blood will be concentrated and the viscosity will be high, which is not conducive to blood circulation and nutrient absorption. If the human body loses 20% water, it will be life-threatening. In the case of heat, high temperature, fever and heavy physical labor, the amount of drinking water should be increased accordingly. Drinking water is the direct source of water needed by human body, such as drinking boiled water or tea. However, water can also be produced in the process of oxidation in human body, and the water needed by human body can also be obtained from diet, such as rice with water content of 15% and meat with water content of 50%.

The relationship between water and exercise: during and before exercise. When the weight is reduced by 2-3% due to sweating, the blood volume will be reduced, which will obviously affect the exercise ability of the human body, so drink water in time and take a small amount as the principle. At the same time, drink light salt water or drinks close to plasma osmotic pressure to keep the balance of water and salt in the body (but in order to lose weight, try to give priority to water).