KidsHealth.org has said that puberty is when bodies begin to develop into adulthood. Between the ages of nine and 14 is when most boys begin to notice changes taking place in their bodies.
Palo Alto Medical Foundation cautioned that puberty starts at different times and lasts for different periods of time for everyone. The sequence of pubertal development usually ranges from two to five years. All of this is very normal.
Kaboose.com said that puberty starts when the brain sends a signal to the testicles to produce testosterone. Testosterone is the hormone that causes most of the bodily changes during puberty.
Children’s Hospital Boston said that the initial change is usually enlargement of the scrotum and testicles. Penis enlargement usually begins about a year later. AVERT.org warns sometimes one testicle grows faster than the other, and it’s natural for one to hang lower.
Pubic hair, said Palo Alto Medical Foundation, also starts to grow. As boys get older, this hair becomes coarser and thicker. Facial, body and underarm hair also begin to grow.
Another sign of puberty, according to Kaboose.com is a growth spurt. KidsHealth.org said when that growth spurt is at its peak, some kids grow four or more inches in a year. At the end of the growth spurt, boys have reached their adult height, or just about.
Palo Alto Medical Foundation wrote that the head, hands and feet are the first to grow; followed by the arms and legs, and finally the torso and shoulders. KidsHealth.org said that boys may notice a bit of breast growth. This is normal and disappears for most by the end of puberty.
Boys will start to notice erections -- which are perfectly normal, according to KidsHealth.org -- occurring more often when they reach puberty.
AVERT.org said that erections usually happen when a boy has romantic or sexual thoughts, or as a result of physical stimulation. However, during puberty, erections sometimes occur without any physical stimulation.
Children’s Hospital Boston went on to say that puberty is when males begin producing sperm. Semen, which is sperm and other bodily fluids, may be ejaculated during an erection.