I invest in my larynx and lungs and this voice I project
My project is like what pros inject
from Wale (Ft. J. Cole & Melanie Fiona) – Beautiful Bliss Lyrics on Rap Genius
Meaning
Similar to how a professional athlete takes care of their body (because their job demands it), Wale invests time and effort into honing his craft and protecting the thing that makes him money (his vocal chords).

And he’s saying that the strength of his music projects resemble that of an athlete on steroids.

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