Naturally, the physical condition and development of up to 12 years – the first of the classic signs of human health. On behalf of the physical health originate all the other parameters and characteristics. In principle, physical development child – is the unity of a large number of indicators, but mostly for its determination only take only the most essential properties – weight, length and circumference of the chest. Basics. Normal weight is born time a child – 3350 – 3450 g, height 52 cm. and chest measurement – 35 cm Normal weight infants increases the bulk of the 10 – 11 day after birth, a doubling of the baby's weight naturally expect to 4,5 – 5 months ., increase by 3 times – To year.

Growth (length) adds a year to 25cm. But to have 3 years of measurements of the baby's head is under 50cm. Volume of the chest of the child in the first days of life, much less the volume of baby's head and compared it to 4 – 6 months. But preterm infants during the first year after birth gorge mainly up to six kilograms, as usual, but tripling and doubling their weight in preterm infants is happening much faster. At the end of the first year, adds weight to the 5 – 8 times. Increase speed of development on average occurs in girls at age 11, while the boys – 12 – 13 years with natural variations in 2 years. By the third year after birth significantly reduced the protective fatty layer, and the child must lose normal the first year of swelling.

But his stomach can last up to 3 years. At the beginning of puberty in women increases the fat layer and may be about 10-25% of the total mass. Do the boys in the first place appears muscular system. Physical development of the child – the process is very complicated, tense and often quite contradictory. Any kid can be characterized by more and some states, often looks like a real disease, but quite strongly differ from them. These "diseases" many are called 'special period of development. " Basically it is certain states, sometimes able to pass without special measures, but, somehow, representing serious risk for the emergence of real illnesses. Examples of these periods include the critical periods of growth, symptoms of teething, puberty. According to the time period can be called dangerous Newborn 3rd to 6 th month. life, 12-15-th years 3 – 4 th years, 6 – 7-years, these periods occur changes in the development of the nervous system, growth and functioning of the immune system.