so you think 20" arm at 30% is impressive then? Thats like 15" at 10%. Your about 190 lbm under there.
No it's not Arnold Jr.
If you were carrying 25% BF EVENLY distributed, which it is not, and your arms were 20 inches, that would mean your arms would be 15 inches WITH NO BF AT ALL. No one has 0% BF.
If my BF were 15% on my arms, that would be 1.5 inches of fat, take off 33%, which would them make them 10% BF overall on the arms and they are still 19+ inches, which is about what they were when I was 215#-220.
But BF is NOT distributed evenly, and arms, at least mine, do not carry 25% BF, more like 15%. I have mch more BF arounbd my abs and back. So do the math Einstein-20+ arms will not go down to 15 inches.