I do not work with chakras.  IMO they are an ancient study that has lost some of its meaning in our hectic, fast paced world (just my thoughts on this).  I do use a flow visualization from the crown of the head and allowing light and colour to go down through the body, enlivening the cells, warming and calming as it removes our stresses.

The seven major chakra centres are located along the spine but at the site of all your major organs in the physical body called the Endocrine system.  How much would metaphysical energies affect the physical?  Just something to think about.

I think that I the endocrine/chakras although variants, run along 'almost' the same lines/with exception to beliefs....from what I have taken in.   The visualization is mentioned a lot - with the white light opening at the crown.
Which is something that I have just begun to work on.  

In regards to the metaphysical energies/physical being.....have to ponder some more.  Do not have an answer/thought process...

..thank you again.