Nonsense. "Essential" body fat is ~5% for men, the lowest I've ever, ever been was 8-9% (and that only lasted a season), but that was measured via BIA, so the error bar was pretty big no matter how carefully done. But I felt fucking invulnerable. I'm sitting at around 17% right now and was even dipping into the dreaded 20% range ~6 mo ago and it feels like garbage.
I don't think <10% is sustainable with the amount of time I can actually devote to training these days, but I'd be pretty happy with a solid 10-12%.
Edited by Jason L, 12 August 2015 - 2157 PM.