Yog means union i.e Oneness
Viyog means Separate
Aviyog means "a = opposite" & "viyog = Separate" so opposite of separate is again Yog i.e Oneness
Born Child (Yogi) Yog i.e Oneness (No differentiation)
Growing Child (Viyogi) Viyog i.e Separate (differentiation e.g Right & Wrong, This or That etc)
Adult(Bhogi) Needs to do Yoga i.e Aviyog i.e Oneness so no problems. Problems arises only when more than one, think....
Sita : I have back pain, Can you help me in this ?
Ram : Yes, When you get pain in forward bending or backward bending ?
Sita : Backward bending
Ram : Oh . . means you moved more in backward than you usually able.
Then simply avoid backward bending for care & Start balancing by moving forward to avoid pain.
"If body resist to balance then first relief it by moving body parts other than back (Spine) e.g. Hand rotation, Legs movement etc."