The two general types of physical development associated with puberty include

Sexual Maturation (Puberty)

Sexual maturation or puberty begins at different ages depending on genetic and environmental factors. Sexual maturity begins earlier today than a century ago, probably because of improvements in nutrition, general health, and living conditions. For example, the average age that girls begin menstruating has decreased by about 3 years over the past 100 years. However, whenever sexual maturation begins, it typically occurs in the same order.

In boys, sexual changes begin with enlargement of the scrotum and testes, typically followed by lengthening of the penis (see Puberty in Boys Puberty in Boys Puberty is the stage during which people reach full reproductive ability and develop the adult features of their sex. In boys, puberty usually occurs between the ages of 10 and 14 years. However... read more ). Next, pubic hair appears. Armpit and facial hair appears about 2 years after pubic hair. The growth spurt usually begins a year after the testes start enlarging. Boys in the United States typically have their first ejaculation between 12½ years and 14 years of age, about 1 year after penis growth accelerates. Young adolescent boys often have slight enlargement of the breasts ( ) that usually resolves within several years.

In girls, breast budding is the first sign of sexual maturation, followed closely by the start of the growth spurt (see Puberty in Girls Puberty in Girls Puberty is a sequence of events in which physical changes occur, resulting in adult physical characteristics and capacity to reproduce. These physical changes are regulated by changes in the... read more ). Shortly after that, pubic and armpit hair appears. Menstruation typically begins about 2 years after breast development starts and when growth in height slows after reaching its peak velocity. In the United States, most girls start their period at 12 or 13 years of age, but there is a wide range.

In both boys and girls, pubic and/or axillary hair may appear first. This appearance may be a normal variation but should be discussed with a doctor.

Milestones in Sexual Development

If sexual maturation begins too early (see Early Puberty Early Puberty Early (precocious) puberty is sexual maturation that begins before the average age. The cause of early puberty is often unknown, but it may be caused by structural abnormalities or tumors in... read more ) or is very delayed (see Delayed Puberty Delayed Puberty Delayed puberty is defined as absence of the start of sexual maturation at the expected time. Most often, children simply develop later than their peers but ultimately develop normally. Sometimes... read more ), doctors typically evaluate children for possible hormonal disorders.

More Information

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

• Growth charts from the Centers for Disease Control and Prevention (CDC) for children age 2 years and older in the United States

  Your Child’s CheckupsPrenatalBabyToddlerPreschoolGradeschoolFitnessNutritionPubertySchoolTeenYoung Adult

  
  In This Section

  Healthy Children > Ages & Stages > Gradeschool > Puberty > Physical Changes During Puberty

  Ages & Stages

  Listen

  Español

  Text Size

  Physical Changes During Puberty

  

  Page Content

  Article Body

   

  Puberty is made up of a clear sequence of stages, affecting the skeletal, muscular, reproductive, and nearly all other bodily sys­tems. Physical changes during puberty tend to be more gradual and steady. This is comforting to many parents who feel childhood passes much too quickly.

  Changes in Body Composition & Height

  Most children have a slimmer appearance during middle child­hood than they did during the preschool years. This is due to shifts in the accumulation and location of body fat. As a child's entire body size increases, the amount of body fat stays relatively stable, giving her a thinner look. Also during this stage of life, a child's legs are longer in pro­portion to the body than they were before. On average, the steady growth of middle childhood results in an increase in height of a little over 2 inches a year in both boys and girls. Weight gain aver­ages about 6.5 pounds a year.

  A number of fac­tors, including how close the child is to puberty, will determine when and how much a child grows. In general, there tends to be a period of a slightly increased growth rate between ages 6 and 8. This may be accompanied with the appearance of a small amount of pubic hair, armpit hair, mild acne, and/or body odor.

  The Influence of Heredity

  Perhaps more than any other factor, your child's growth and ultimate height will be influenced by heredity. While there are exceptions, tall parents usually have tall children, and short parents usually have short children. Those are the realities of genetics.

  Concerns About Growth

  If your child seems unusually short or tall relative to his friends the same age, talk with your pediatrician. A true growth disorder can sometimes be treated by administering growth hormones; however, this therapy is re­served for young children whose own glands cannot produce this hormone. Doctors do not recommend this treatment for healthy boys and girls who may want (or whose parents may want them) to grow to be 6 feet tall instead of 5 feet 8. See When a Child is Unusually Short or Tall.

  Growth Spurts

  Just as height can vary from child to child, so can the timing of a child's growth. Despite the averages mentioned above, children have a tendency to grow in spurts.  Thus, they may grow faster at times and slower at others.  Some children grow as much as three times faster during a particular season of the year, compared with their "slow" seasons. These individual variations in timing—along with hereditary factors—are largely responsible for the wide variations in size among children the same age. Height differences among children in a typical elementary school classroom can range from 4 to 5 inches.

  Although boys and girls are generally of similar height during middle child­hood, that changes with the beginning of puberty. Particularly in junior high school, girls are often taller than their male classmates, but within a year or two, boys catch up and usually surpass their female classmates. About 25 per­cent of human growth in height occurs during puberty.

  Nutrition's Influence on Physical Development

  A number of other factors—so-called environmental influences—can affect physical development as well. Nutrition is important to normal growth processes. Parents should make an effort to ensure their child con­sumes a well-balanced diet. A child's need for calories rises during times of rapid growth, gradually increasing as she moves through middle childhood into puberty. However, if the calories consumed exceed those expended, a child may develop a weight problem. See Energy In: Recommended Food & Drink Amounts for Children.

  A Word about Picky Eaters

  Some parents worry that their child is not eating enough. Even with what seems to be relatively low food intake, however, children can grow at normal rates.

  If your school-age child is a picky eater, do not worry that this frustrating behavior is impairing her growth. These fluctuating eating habits may be due to normal, slow-growth periods or simply uniquely personal, unpredictable preferences or distastes for certain foods.

  In general, children outgrow these food preferences without any harm to their physi­cal well-being. As long as a child is gaining weight appropriately (4 to 7 pounds per year) and is eating a healthy variety of foods, his nutritional needs are being met.

  The Importance of Regular Exercise  

  Children also need to exercise regularly to ensure normal physical devel­opment. Those who spend their free time watching TV, playing video games, or engaging in other stationary activities rather than playing outdoors may have impaired bone growth. When physical activity is in­creased, bones are denser and stronger. However, there is no evidence that a very strenuous exercise program will help your child grow faster or bigger. Running marathons, for example, will not stimulate physical growth. See Energy Out: Daily Physical Activity Recommendations .

  Pre-Puberty Changes

  A number of other changes occur during middle childhood:

  • Children become stronger as their muscle mass increases.
  • Motor skills—in both strength and coordination—improve.
  • A school-age child's hair may become a little darker.
  • The texture and ap­pearance of a child's skin gradually changes, becoming more like that of an adult.

  First Signs of Puberty

  Puberty often begins earlier than parents think:

  Girls

  • Breast budding in girls starts around age ten, with some girls starting as early as eight and others not starting until thirteen.
  • Girls should be checked by their pediatrician if they begin puberty before age eight.
  • The peak growth pe­riod (in height, weight, muscle mass, and the like) in girls occurs about one year after puberty has begun.
  • Menstruation usually starts about 18 months to two years af­ter the onset of puberty. On average, the first menses occur just before girls turn thirteen.
  • If a girl shows no signs of puberty by age 13, consult with your pediatrician.
  • See Physical Development in Girls: What to Expect.

  Boys

  • Boys enter puberty about one year later than girls. The first sign is enlarge­ment of the testes and a thinning and reddening of the scrotum, which hap­pens at an average age of eleven but may occur anytime between nine to fourteen years.
  • Boys should be checked by their pediatrician if they begin puberty before age nine.  
  • For boys, the peak growth period occurs about two years after the beginning of puberty.
  • If a boy shows no signs of puberty by age 14, consult with your pediatrician.
  • See Physical Development in Boys: What to Expect.

  How to Discuss These Changes with Your Child

  Your child needs to understand the phys­ical changes that will occur in her body during puberty. There are many opportunities during this time of life for you to talk to your child about what she's experiencing. You should emphasize that these changes are part of the natural process of growing into adulthood, stimulated by hormones (chemicals that are produced within the body).

  Keep track of your child's bodily changes, while fully respecting privacy. As the age ranges above indicate, there are wide variations of "normal" in the time when puberty begins. Remind your child that while her friends will grow at different rates, they will eventually catch up with one another.

  Additional Information:

  • Physical Development in Boys: What to Expect
  • Physical Development in Girls: What to Expect
  • Physical Development: What's Normal? What's Not?
  • When a Child is Unusually Short or Tall
  • When Puberty Starts Early
  Last Updated12/19/2014SourceSection on Endocrinology (Copyright © 2014 American Academy of Pediatrics)

  The information contained on this Web site should not be used as a substitute for the medical care and advice of your pediatrician. There may be variations in treatment that your pediatrician may recommend based on individual facts and circumstances.

  Which development changes are associated with puberty?

  In puberty, children get taller, heavier and stronger. There are also changes in children's sexual organs, brains, skin, hair, teeth and sweatiness.

  What factors cause the physical changes associated with puberty?

  Genes. A person's genetic makeup can affect the timing of puberty and what the changes look like. Diet/nutrition and exercise before and during adolescence. Overweight females, for example, are more likely to have their first period and experience breast development at younger ages than their peers.

  What are 3 physical development characteristics of an adolescent?

  Physical changes of puberty mark the onset of adolescence. These changes include a growth spurt in height, growth of pubic and underarm hair, and skin changes (e.g., pimples). Males experience growth in facial hair and a deepening of their voice. Females experience breast development and begin menstruating.

  What are the characteristics of physical development of adolescence stage?

  In early adolescence, the dominant physical development characteristics include growth spurts, puberty, and neural change (Patton et al., 2016). These noticeable physical changes lead to increased self-awareness among young adolescents (Harrison et al., 2019).