Wallace Mac is a phrase used to describe a weak man, both mentally and physically. This phrase is reference to a weak mindset and a "bad back".
The phrase can be used to describe pain or used as sarcasm.
There's a RFTS coming up. Waste of time. Might just Wallace-Back it.
Feeling a bit stiff from sleeping funny last night, my mattress has given me real bad Wallace-Back.
I nutted in my misses and felt a horrible twitch as I did the full unload. I tried to stand up but my Wallace Back had went.