Knowledge: Extreme sports are very intense as it uses all parts of muscle and takes a long time to recover compared to regular sports. On the other hand, bleaching hair consumes a lot of hours like 1 hour and more as it is a slow process.

Conversation:
I just dyed my hair light purple. I am really excited about it!
Neat, hair coloring can be done at home or by a hairdresser, which way did you go?
I went to a hairdresser to have it done.
Cool, the Celtic people was described by Diodorus Siculus, a Greek Historian, to have dyed their hair blonde.
That's really cool! How did they manage that?
They bleached it through washing it in lime. The bleaching too long time.
Oh wow. That sounds very intense. Do you know how long it takes to do that?

Response: Ah yes. Bleaching hair consumes a lot of hours like 1 hour and more as it is a slow process.