I work out a whole lot, maybe 7-8 hours a week and am pretty good sized and all that... 5'11" and 152 pounds. Arm measurement- 15 inches, chest- 40 inches and waist is around 30.5 inches. I got my body fat measured and it was like 4%. Is that Ok? I know the standards are a little different for athletes and all that but still it seems kinda low..