Physical Development During Adolescence


Adolescence marks a time of great change in a child’s life; it bridges the gap between childhood and adulthood. Adolescents go through emotional and physical changes, and develop at their own pace based on genetics and environmental factors. The changes themselves, however, are the same for all adolescents.


Adolescents go through puberty to develop their reproductive systems. The body releases the gonadotropin-releasing hormone, which signals the pituitary gland to release follicle-stimulating and luteinizing hormones. These gonadotropins signal gonads to produce other hormones that eventually stimulate changes in the brain, bones, muscle, fat composition and reproductive organs.

Secondary Sex Characteristics

The hormonal changes during puberty stimulate the development of secondary sex characteristics, features that set apart the sexes without being directly related to the reproductive system. While secondary sex characteristics in girls include breast enlargement, additional subcutaneous fat and widening of the hips, boys will experience penis growth, facial hair growth and a deepening of the voice. Both genders will experience pubic hair growth, underarm hair growth and increased oil production and sweat gland activity.

Brain Development

The brain isn’t fully developed until a person reaches his 20s, according to Barbara Strauch, author of Primal Teen and the medical science and health editor of The New York Times. Connections between the neurons that control emotional, mental and physical capabilities are incomplete in a teenager’s brain. As a result, teens may have wildly fluctuating emotions and can be more impulsive.

Time Frame

The majority of girls begin to develop sexually between the ages of 8 and 13 years, according to KidsHealth. Most girls experience a growth spurt (or phase of extreme growth) between ages 10 and 14. Boys develop a little later, typically between ages 10 and 13, and continue through age 16.

Height and Weight Changes

An adolescent’s ultimate height is mostly determined by genetics. Girls tend to gain height more rapidly between ages 12 and 15, according to KidsHealth. Boys tend to hit their growth spurt about two years later. An adolescent can grow up to four inches in one year. Adolescent bodies also gain weight to take on a more adult shape. For boys, this means becoming more muscular. For girls, this means developing additional body fat in the hips and breasts.

About this Author

Christa Miller has been writing since the day she was able to pick up a pen. She attended San Francisco State University to earn her Bachelor’s degree in creative writing with a minor in journalism. Her web articles can be found on such sites as eHow, Travels and LIVESTRONG. When she’s not writing, Miller works as a therapeutic massage therapist in Phoenix, Ariz.