Pain standing upside-down? No, no, it is a spiritual practice (4)
I believe the answer is:
yoga
'spiritual practice' is the definition.
'Yoga' can be an answer for 'practice' (I have seen 'Hindu practice ' mean 'yoga' so perhaps 'practice' could also mean 'yoga'). I am unsure of the 'spiritual' bit.
'pain standing upside-down? no no it is a' is the wordplay.
'pain standing' becomes 'goy' (I can't explain this - if you can you should give a lot more credence to this answer).
'upside down?' is a reversal indicator (I've seen 'upside down' mean this).
'no' indicates named letters should be taken away.
'no' becomes 'n' (common abbreviation).
'it is a' becomes 'an'.
'goy' written backwards gives 'yog'.
'an' with 'n' taken out is 'a'.
'yog'+'a'='YOGA'
Can you help me to learn more?
(Other definitions for yoga that I've seen before include "Hindu philosophy of tranquility through physical exercise" , "Hindu course of exercises and postures" , "System of physical and mental exercise" , "Eastern discipline" , "Philosophy with exercises" .)