Terminal length question

[Latin Tea]

My son and I were discussing long hair and he asked if it ever stops growing. I told him that many people have a terminal length where the hair just won't grow any longer. Well, he asked me an interesting question. Here it is:

If you grow your hair to knee length and it stops growing (indicating terminal length) AND then you cut it to waist length and it starts growing again, how did your hair know that it was cut?

Anybody want to tackle that? :confused:

[Dars]

Because hair does keep growing at terminal length. Hair sheds all the time throughout life, so hairs are constantly being replaced at terminal.

[teela1978]

Its been mentioned before (by I think spidermom) that calling it 'terminal time' might be an easier way to explain it. Each hair follicle goes through a cycle of growing, resting, and shedding that can last for several years. The longer the growing cycle is, the longer your terminal length will be because the hairs have more time to grow out of your head.

did that make any sense?

[spidermom]

A hair does not start growing again once it has stopped. However, there are always newer, shorter hairs coming along to replace the old hairs when they shed out.

If a hair reaches the end of its growth cycle, it will shed out no matter how short or how long it is.

[Latin Tea]

I guess I didn't understand 'terminal length' very well. Your explanations have helped. Should make for interesting dinner conversation tonight. Thanks!

[VenusHalley]

Its been mentioned before (by I think spidermom) that calling it 'terminal time' might be an easier way to explain it. Each hair follicle goes through a cycle of growing, resting, and shedding that can last for several years. The longer the growing cycle is, the longer your terminal length will be because the hairs have more time to grow out of your head.

did that make any sense?



So does that mean it would be easier to reach the terminal lenght for the first time and it would take a longer time when it is cut (because the "old" hair that has been cut would not grow anymore and you would have to wait for the newer - short - hairs to reach the lenght)?

I hope my question makes sense.

[Isa-belle]

So does that mean it would be easier to reach the terminal lenght for the first time and it would take a longer time when it is cut (because the "old" hair that has been cut would not grow anymore and you would have to wait for the newer - short - hairs to reach the lenght)?

I hope my question makes sense.
Yes, that's what I understood :)

[teela1978]

So does that mean it would be easier to reach the terminal lenght for the first time and it would take a longer time when it is cut (because the "old" hair that has been cut would not grow anymore and you would have to wait for the newer - short - hairs to reach the lenght)?

I hope my question makes sense.

I don't think so. My understanding is that most of your hairs are growing, the hairs that have stopped growing should be in the minority. There should be newer hairs at all lengths, so wherever you cut it to there should be fresh hairs just above that, and they can keep right on growing to terminal.

[aprilmay]

Interesting discussion. I always cut my hair when it reaches a certain length because it starts to snarl easily and look ragged at the ends. I have my own terminal length when I feel my hair needs a good trim.