I have heard a lot about the story (or maybe even legend) about the fact that the actor Kevin Costner was very short when he was in High School but would eventually shoot up in height during those high school years.
I was watching the Youtube video entitled “Inside The Actor’s Studio – Kevin Costner” and James Lipton in his interview of Kevin Costner around the 4:33 minute mark asks Costner point blank “How tall were you when you went into high school?” and Costner would answer with “I was 5′ 2”. He would recount the story of him going to his mother and asking her “Am I going to grow?” and she would reply with “I swear you are going to grow honey” that he would indeed grow taller so he felt better.
Lipton would go on to ask Costner about which college/university he went to and Costner would reply with “Cal State Fullerton” where the tuition was just $99 and majored in Marketing & Finance. I guess the college fees back then was much cheaper.
So how tall is Kevin Costner today? From the well known website CelebHeights.com profile for Kevin Costner they list him at 6′ 1″ (1.85 m) with other people saying he might be closer to 6′ 0″.
Whatever he is listed at now we can see that to go from 5′ 2″ to over 6 feet is a major transformation.
Let’s see the growth progression and see whether it was abnormal. Most people in the US start High School around 14-15. Most boys end puberty around 19-20. So Costner had on average 5 years for growth left. If he did reach 6′ 1″ then he got 11 inches, which is very big. Only the story of Dennis Rodman’s transformation would be more dramatic.
I have found from my research that there is usually 1 year in a person’s life, around the first year of the onset of puberty where a person would gain 4-5 inches in just say 3-4 months, usually during one’s sleep in the summer time.
A 10-11 inch transformation is around 2-3 times greater than average. If the growth was linear and constant, that would be around 2 inches of increase a year, which is at the rate which can only be seen in children before puberty.
So what could be the biological mechanism to cause Costner to gain such a big growth spurt?
I would guess that what happened to his body was that it was experiencing a phenomena known as catch-up growth, where the growth plates sensecense was slowed down for some reason for a longer time than most people. If the senesence slows down, that also slows down the rate of long bone longitudinal growth in the years before the onset of puberty. However this also means that the chondrocytes in the reserve zone of the growth plates are not used up. Something causes the trigger to get the chondrocytes to finally start to stack and hypertrophize at the rate they were supposed to. He still have cartilage and chondrocytes left and in a shorter time frame his body pushed him to the level ie height which he was always supposed to reach. In my best guess, Coster was always supposed to reach 6′ 1″ in height, it was just that his chondrocytes maybe never got the right amount of stimulation to start the proliferation and hypertrophy stages. Eventually the resting zone would run out of chondrocytes and the creeping of the vascularization would cause the lower to reach the top with the process of calcification. So my educated guess is that Costner’s body was experiencing the phenomena of catch-up growth. This might also explain some of the growth we see in other people, but most males which have a freakish rate of growth later in their development years.
The lingering question we should be asking ourselves are, “Could More Stories About Rapid Dramatic Growth Spurts In One’s Late Teen Years Be True?”