View Full Version : Elasticity affecting Length?

February 7th, 2015, 06:50 AM
We all know about shrinkage on curly hair as it dries is a sn of healthy hair with a good moisture and protein balance.
Now im wondering, is it possible for straigther hair types to shrink as well as the condition of the hair inproves. Kind of like a rubber band that snaps back properly, when before it was a little bit overstretched. if theres hygral fatigue and swelling of the shaft it would be possible for the same to work lengthwise, no.

The thing is, the better i take care of my hair, it sometimes seems to get shorter by itself when measuring. i think i have a normal growth rate but its often up and down. recently n the winter my hair did not seem to grow alot and i was thinking, as it still kept improving condition, maybe im not to stupid to use the measuring tape, but the har is tightening up and thats why i can sometimes loose a centimeter, which isnt that much around classic length? its definitely the healthiest it has ever been and not breaking off or anything like that. my routine is quite protein heavy, but by the look and feel of it my hair loves that.

i hope im not being confusing right now. what do you guys think, does that make sense or is it rubbish?

February 7th, 2015, 08:23 AM
Awesome question, MINAKO! :D

I think all hair has some elasticity and shrinks when dry, stretches when wet, but the more damaged it is, the more water (and other stuff, e.g. oils, dye molecules, different conditioning ingredients) it can absorb and later lose, so more swelling and more shrinking, which we want to avoid ideally, like we want to avoid a stretched out rubber band effect.
Sure shrinkage of curls is much bigger compared to this effect, but even straight hair has this.
Check this interesting webpage (http://www.hair-science.com/_int/_en/topic/topic_sousrub.aspx?tc=ROOT-HAIR-SCIENCE^SO-STURDY-SO-FRAGILE^PROPERTIES-OF-HAIR&cur=PROPERTIES-OF-HAIR)out: it explains how they use an extensiometer to measure hair elasticity.
"Despite the close fitting scales of its cuticle and the sebum which naturally coats it, a hair in good condition can absorb more than 30% of its own weight of water. If the hair is already damaged by other factors, this percentage can reach 45%. Its length can thus increase by 2% and its diameter by 15% to 20%! These properties vary greatly depending on the shape of the hair."
The text later mentions how much stretching it takes before hair breaks, which might help understand hair's elasticity:
"Breaking under a strain of 60 grams after an elongation of 40%, African hair seems to be the most fragile. At the other end of the scale, Asian hair is the strongest, withstanding a weight of 100 grams and an elongation of 55%. For either of these features Caucasian hair occupies an intermediate position."

February 11th, 2015, 09:12 AM
thank you meteor!
that article explains it amazingly well. i think my hair did suffer from hygral fatigue in the past, because even after i started CO washing, i would often do that daily until i learned not to and just mist my hair lightly, use oils religously etc. so i guess half of my hair still remebers that.
however, i alsodo keratin treatment and i guess these are somewhat encouraging the shrinkage of hair, so especially right after a treatment it seems not to grow as fast. the elasticity is still good tho, it does not snap easily wheter wet or dry.
usually i measure my hair after washing it, so without the treatment affecting my hair it did have a good chance to swell up also in length i guess. now im at a solid 44" and did not expirience alot of growth during the past 12weeks. at the same time i have to say that the treatment i did before that was the most potent i ever did. i only measure about every few moths, so maybe i didnt notice the dramatic shrinkage right after.