In the sudden growth of adolescence, the growth of height is very fast. The main reason for growing taller is the development of bones. The height of boys can increase by 7 ~ 9 cm every year, and the maximum height can reach 10 ~ 12 cm. Girls can increase by 5 ~ 7 cm per year, with a maximum of 8 ~ 10 cm. This mainly depends on the growth of lower limbs and spine. Generally, the height of women stops growing at the age of 19 ~ 23, while that of men stops growing at the age of 23 ~ 26. At this time, because the epiphysis is closed, it cannot be regenerated. Adult women are shorter than men because the epiphysis of women is generally closed earlier than that of men.
1, the method of predicting adult height with children's body length
Male height = length at birth (cm)÷0.2949；; Female height = length at birth (cm) ÷ 0.438+009. It should be noted that this formula is only applicable to normal full-term newborns; If the length data can be accurate to 0. 1 cm, the prediction of height will be more accurate.
Male height = height at 3 years old ×0.545+ average height of parents × 0.544+37.69 (cm); Female height = height at 3 years old ×0.545+ average height of parents ×0.544+25.63 (cm).
2. Prediction formula of human standard height
Male height = (father height+mother height) × 1.08÷2
Female height = (father height ×0.923+ mother height) ÷2
The above formula generally conforms to the genetic principle of "height increases to produce height, height increases to produce height, and height increases to produce height".
Second, the factors affecting the height of teenagers
1, sexual maturity sooner or later
Mature age will affect the rapid growth of height sooner or later. Generally, people who experience rapid growth earlier will reach the finish line faster; What happened later came to an end. When precocious girls no longer grow taller, late-maturing girls still grow taller. Therefore, girls with precocious puberty are taller. The fastest growing period of height is before puberty. In the year before menarche, the height of girls can increase by 7 ~ 8 cm; The peak of boy's height growth is in the first year of adolescence, about 13 ~ 14 years old, and the height growth can reach 10 ~ 12 cm. But relatively speaking, people with normal development are taller than those with early or late development; Especially men.
2. Nutrition intake
In a sense, height is "piled up" by nutrients (especially protein). There are 500 ~ 65438+ ten thousand substances that make up protein, and the eight essential amino acids that make up these protein depend on food supply. If food can provide enough 8 kinds of essential amino acids, it can accelerate the synthesis of protein, and contribute to the growth and development of various tissues and organs in the whole body, especially the growth and development of bones and iliac cartilage. Experiments on preschool children show that the height and weight of the experimental group with 0.5 g lysine added to each meal of bread are significantly higher than other children.
Step 3 sleep
When biologists study the secretion law of endocrine glands, they find that for children, sleep time is long and sleep time is long. The growth of height depends on the growth of epiphysis, which is controlled by endocrine glands. The endocrine hormones that control height mainly include auxin, luteinizing hormone and sex hormones secreted by pituitary gland, among which growth hormone plays the most significant role. The secretion of growth hormone has its obvious regularity, that is, it is secreted less during the day and more during sleep at night. The researchers found that when children sleep deeply 1 hour, the secretion of growth hormone is 5 ~ 7 times higher than that during the day, and the secretion of sex hormones and luteinizing hormone is also very strong during deep sleep. Obviously, this is very beneficial to the growth of children's height. Adolescence is the most exuberant period of growth hormone and androgen secretion. The main function of growth hormone is to make the bones of limbs grow; Androgen makes bones thicker and stronger. The secretion of these two hormones is particularly strong during sleep, so teenagers should ensure adequate sleep and sleep at least 8 hours every night.
4. heredity
According to research, 75% of the final height of human body depends on genetic factors. In other words, in general, parents are tall and children are tall; Parents are short and children are short. However, the height of parents is not the only factor that affects the height of children, and the external factors, that is, environmental conditions, can not be ignored. External factors mainly refer to nutrition, living habits, physical exercise and so on.
5. Sports
According to the survey, a year's physical exercise can make the height of boys longer than that of their peers who don't exercise 1 ~ 2 cm, while that of girls is 2 ~ 3 cm. Pupils who exercise regularly are about 5 cm taller than those who don't exercise. Physical exercise can promote physical growth. First, it can promote the secretion of growth hormone. Second, it can strengthen the blood supply of bone cells, which is beneficial to improve the proliferation of epiphyseal cartilage. Thirdly, it can stimulate the proliferation of epiphyseal cartilage. According to research, the secretion of growth hormone increases obviously after exercise, and at the same time, exercise will also exercise muscles and bones to make them stronger. Therefore, researchers at home and abroad unanimously affirm that sports contribute to height growth, such as touching height, climbing pole or rope ladder, pull-ups, cross stretching, skipping rope, jumping rubber bands, kicking shuttlecock, horizontal bar hanging, swimming and so on. These exercises will increase the flexibility of joints and ligaments and contribute to the development of height. Weight-lifting, barbell, shot put, discus and other weight-bearing training should not be used as a routine training program for teenagers before 18 years old. Even after puberty, it is not suitable to do such exercise, so as not to affect the development of height.
6. Mental factors
Studies have found that children with severe mental trauma are stunted or even stagnant. This is because bad emotions will affect the functions of the brain and endocrine system, from light to heavy, it will affect the physical development and lead to various diseases. Therefore, sadness and depression will not only make children and adolescents susceptible to various diseases, but also affect their growth and development, and even lead to "premature aging".
7. Child development
In recent 20 years, the average height of countries in the world has increased by 1 cm every 10 years. The human body tends to be taller from generation to generation. According to the data report, in the past 30 years, the average height of Japanese 14-year-olds increased by 8.2 cm, but in 20 10, Japanese 19-year-olds were 2 cm shorter than those in China. During the 80 years from 185 1 to 193 1 in Sweden, the height of soldiers increased from 166.6 cm to 174.5438+0 cm, an increase of 7.5 cm. The average height of Dutch conscripts is 1858. The former Soviet Union measured soldiers' bones in the18th century, and found that the average height of soldiers increased by 20 cm in the past 250 years, reaching 175 cm. In the nearly 20 years after the Cultural Revolution, the average height of China 18 ~ 25-year-old urban youth increased by 2.3 cm for men and 2. 15 cm for women.
Third, the scientific method for teenagers to grow taller.
1, supplement nutrition
Nutritional balance is the standard of a healthy diet. The good development of the body needs a healthy diet, and nothing can grow taller or increase in a short time after eating. From a scientific point of view, it is the best way to cross-ingest nutrition from various foods. Seven elements of nutrition: protein, fat, carbohydrates, vitamins, water, cellulose and minerals are indispensable. Only when the nutrition is fully balanced and the physical condition reaches a good cycle will the figure grow taller.
(1) protein is well supplied.
Because protein is the best "building material" for children's growth and development, adults need about 80 grams of protein every day, and children need more, not only to ensure the quantity of protein, but also to pay attention to the quality of protein.
Animal foods, such as fish, meat, eggs, milk, etc., contain relatively complete amino acids necessary for human body and have high nutritional value, so their supply and demand should be guaranteed. The combination of plant proteins, such as beans, peanuts, vegetables and animal foods, can further improve the nutritional value of protein, learn from each other's strong points, and enhance the absorption of vitamins and minerals. It is reported that lysine and nucleic acid are closely related to height. These foods are rich in lysine and nucleic acid and should be given to children regularly.
(2) abundant calcium supply
Preschool children need 600 mg of calcium every day, primary school students need 800 mg, and middle school students need 1200 mg. If the calcium supply in food is insufficient, rickets will occur in infants and children of school age will not grow tall. Therefore, attention should be paid to the supply of foods rich in calcium, such as milk, beans and their products, sesame sauce, kelp, shrimp skin, melon seeds, green leafy vegetables and so on. Supplementing infants and school-age children with appropriate calcium and cod liver oil is beneficial to the growth of height. Children should be encouraged to go outdoors to bask in the sun, because ultraviolet rays in the sun can convert dehydrocholesterol in the skin into vitamin D, which helps to absorb calcium.
(3) advocate eating less sugar
Eating too much sugar will easily affect children's appetite and reduce their food intake, which will inevitably affect the absorption of nutrients. Moreover, when there is too much sugar, the metabolic intermediates pyruvate and lactic acid will increase, which requires alkaline calcium to neutralize, and the consumption of calcium is bound to increase, thus affecting the growth of bones. In addition, foods containing more oxalic acid, such as water bamboo, bamboo shoots, green garlic, spinach, etc., can combine with calcium to form insoluble calcium oxalate, so that the calcium in food can not be absorbed and utilized by the human body, so pay attention to the method when eating.
Step 2 Exercise moderately
Exercise can increase the exercise of muscles and bones and promote the healthy development of bones and muscles. For example, teenagers who love playing basketball will be taller. Exercise itself can make people fall asleep and promote the secretion of growth hormone. After the body is fully exercised, the appetite increases and the nutrition is well absorbed, which provides a material basis for growth and height. Relevant surveys show that people who have exercised during the day secrete more growth hormone at night than those who have not exercised during the day. Adults are like this, and children will behave more obviously; However, it should be noted that strenuous exercise that consumes too much physical strength will also stop the body from growing.
3, a good attitude
The mentality of teenagers is also a point that parents need to pay attention to. A healthy and correct attitude and stable mood are conducive to the healthy growth of teenagers. Depression will affect health, resulting in height is also affected. Insufficient parental care and emotional instability will reduce the growth hormone secreted by the pituitary gland, thus affecting development. In addition, due to emotional instability, appetite will decline, sleep will become shallow, and growth will naturally be affected.