Particularities of adolescence – Physical Features
By adolescence include the period between childhood and adulthood (usually between 10 and 20 years), when there is a rapid biological and mental development. Start and duration of this period is largely dependent on external factors. In the next decade the number of adolescents will grow, and representatives of ethnic and racial minorities among them will be greater than in the general population. Thus, adolescents become poorer, and medical assistance will be available to them at least. Today, the US teenage worst provided with health insurance.
The doctor needs to understand is, biologically and mental characteristics of a teenager, his social problems, to know the intricacies of the legal and deontological adolescent health care.
Puberty – a chain of biological processes that lead to the formation of the reproductive function. Its onset and duration depend on the gender, social and individual characteristics. Under the influence of changes in the system of hormonal regulation (hypothalamic-pituitary-gonadal axis) vary skeletal development and structure of the body, there are secondary sexual characteristics. However, the mechanism of activation of the system is unclear.
When puberty as a result of the activation of the adrenal glands and gonads are formed secondary sexual characteristics. To evaluate the use of this process step Tanner puberty that correlate with bone age rather than a passport.
In girls, puberty stage is determined by the development of breasts and pubic hair distribution; boys – on the development of the external genitalia and pubic hair distribution.
Puberty in girls starts with the growth of the mammary glands in 11.2 plus or minus 1.6 years, menarche occurs at 13.3 plus or minus 1.3 years, the total duration of puberty – 4 years (1.5-8 years) . Puberty in boys starts with the increase in testicular 11.6 plus or minus 1.1 years, the first pollution occurs at 13.5-14.5, the total duration of puberty – 3 years (2-5 years).
During puberty (in spite of the possible deviation in time of its beginning and duration) a teenager going through a very definite successive stages of growth and development. Knowledge of these stages helps to identify the disease, which manifest them in adolescence.
Musculoskeletal system: features of development in adolescents
Approximately 25% of its final height a person acquires during the pubertal growth acceleration. Usually girls acceleration begins at age 12 (I-2-3 Tanner stage), and the boys – in 14y.o. (3-4-th stage according to Tanner). At the same time the girls are growing at an average rate of 9.0 plus or minus 1.03 cm per year and reach a final average height 163 cm in 16 years; boys grow by 10.3 plus or minus 1.54 cm per year, reaching a final average height of 177 cm in 18 years.
In adolescents, the growth estimate for the growth rate curves with regard to the stage of sexual development. Bone age is determined by the hand and wrist radiographs.
Body composition: characteristics of adolescents
During the pubertal growth acceleration is typed about 40% of the ideal weight.
In boys, during this period is increased fat-free body mass from 80 to 90%. Subsequently the body growth slows down, and the proportion of fat increases again so after puberty fat-free body mass of more than 80%.
Girls for the entire period of puberty lean body mass decreases gradually from 80 to 75%.
Muscle mass reaches a maximum shortly after the completion of pubertal growth acceleration; for boys it is more than that of girls.
Cardiovascular and respiratory systems in adolescents
In puberty stroke volume, cardiac output and blood pressure increase and your heart rate drops. Increasing light. Boys under the influence of androgens thyroid cartilage forms a protrusion on the front surface of the larynx, resulting in lengthening the vocal folds (men are three times longer than in women), and the voice becomes lower.