Last updated on October 15, 2022
Question:
Hey,
I have a question: Why is it that at early 15 males are thin and long and at the end of 15 males are bigger and look like adults?
Answer:
![](https://i0.wp.com/growingupboys.info/wp-content/uploads/2020/07/Tanner-Stage-3-Example-179x300.jpg?resize=179%2C300&ssl=1)
![](https://i0.wp.com/growingupboys.info/wp-content/uploads/2020/07/Tanner-Stage-4-Example-300x225.jpg?resize=300%2C225&ssl=1)
It is not a factor of age but that stage of development a boy is in. Typically at the beginning of age 15, a boy is just finishing off his growth spurt. That rapid growth used up a lot of his body fat and his long bones make him look stretched or thin. By the middle of stage 4 (a year later), he is starting to develop muscles, which fill out his frame and gives him a more adult look.