It might be that Mr. Loggins is alluding to a frame of mind; loosely translated as: a secondary, or lower level of outlook on life, or more literally: secondary life force.
I hear that he wanted to actually use “secondary life force”, but couldn’t fit it to the beat.
Well, now the zombie re-resurrects, but with much less life force …
That wasn’t The Zombies 
.
I love when people screw around with the language. My favorite: Then the Grinch did the same to the other Whos’ houses, leaving crumbs much too small for the other Whos’ mouses. I plotz every time.
Beta means son in Hindi and chi is like the Chinese word meaning life force/energy, etc. The song was written for the birth of his brother’s son.