ATG = Ass To Grass (often with reference to way below parallel squats)
Rip,
Maybe this'll help the newbie's...it ain't comprehensive!
GOMAD - gallon o milk a day
TUBOW - terribly useful block o wood
RM - repetition maximum
PR - personal record
Metcon - metabolic conditioning
CF - crossfit
DL - deadlift
PC - powerclean
PP - Practical Programming by our own "Uncle Rip" now aka "dad"
SS - Starting Strength by the same aformentioned
ATG = Ass To Grass (often with reference to way below parallel squats)
TFH - too fucking heavy
BW = Bodyweight
OH = Overhead
AxB = A sets of B reps (ie: 3x5)