http://www.drweil.com/drw/u/id/QAA53794

http://sportsmedicine.about.com/od/fitnessevalandassessment/a/Body_Fat_Comp.htm

http://jap.physiology.org/cgi/content/abstract/77/2/933

and…
http://bodybuilding.about.com/od/bodybuildingfaq/f/losefatgainmass.htm

Site 1 – …”For men, essential body fat makes up about three percent of total body weight. The healthy ranges in men are from 8-19 percent for those between the ages of 18-39, from 11-21 percent for those aged 40 to 59 and 13-24 percent for those over 60.”

Site 2 – …”Your ideal weight and fat-lean ratio varies considerably for men and women and by age, but the minimum percent of body fat considered safe for good health is 5 percent for males and 12 percent for females.”

Site 3 – (based on US Army research for the Journal of Applied Physiology) …”Our results suggest that 4-6% BF or approximately 2.5 kg fat represents the lower limit for healthy men, as assessed by DEXA or by underwater weighing.”

From what I can tell, the overwhelming consensus seems to indicate that anything less than about 5 – 6% is getting too low. Perhaps the most revealing site is … where they actually recommend that one get to 10% or just slightly lower if one wishes to gain muscle while losing fat at peak efficiency.

I eased back into this over three weeks ago so I doubt that loss fo water from restricted diet is at play. Plus, my pants are noticeable looser in the waist.

While it is true that one has to have the abs to show…everyone has abs. Not everyone has them developed well (of course), but everyone has them. You mentioned Poliquin’s latest article on t-nation. I checked there and while a part of his answer says that “…the upper row of the abdominals can show up at 15%”, he not only starts his answer to the question “How low does your body fat percentage generally need to be in order to start seeing abs?” with the answer of 9.8%…but goes on to state “If you can see the linea alba (which means the “white line” ) — the vertical line in the middle of the rectus abdominis — that’s at least 9.8%. In other words, you’d see all the rows.”

That seems to blend in with what I’ve been reading elsewhere…that about 10% body fat is where the abs start to pop for “most” people. There are always exceptions, but most of us fall into the “rule”…not the “exception”. I’m not trying to knock the concept of a strong, well-developed core (for any number of reasons)…my comments are focused just on when one might expect to see them.

If all one truly cares about is increasing one’s overall strength, then just attaining and maintaining a healthy level (13 – 18% for us guys) is all that is really necessary. However, if part of the reason someone is chasing a fitness goal is to get that “six-pack”, knowing where the line is can sure make attaining that goal less frustrating.

@Michael
If you drop your body fat, but have no abs to show, you still won’t see much. Building abs (strength) is as important. A lot of people think lowering your body fat is the solution, and while your abs won’t show if you carry 30% body fat, you can see them around 15% body fat. You’re familiar with t-nation, check Poliquin latest article, he says the same thing.

You can see boxers or other martial artists at weight ins with 5 or 6% BF, so that they fit in their weight class, but as soon as they step off the scale, they drink and eat huge amounts of food, to get their body the necessary energy to kick ass in the ring.

Then when you see them fighting, they still look all muscular and they are as fit as they can get. These guys continue to make great gains in strength while staying in their weight class.

Gaining and losing weight is simply a matter of the right nutrition.

http://www.t-nation.com/readArticle.do?id=1268956

With personal experience in gaining muscle while losing fat and not changing my scale weight at all, I can definitely say it is possible…but one has to care enough to monitor incoming calories, especially their composition. In the last month I moved from 14.1% body fat to 11% body, and my total body weight only changed by 0.05 lbs (it went down by that amount).

I too would like to see a reference to your comment about maintaining a body fat percentage below 10%…I’ve never heard or read that anywhere. Sure, most probably don’t…but that doesn’t mean it isn’t possible or even practical with the correct diet and exercise load.

It’s also a bit misleading to suggest that anyone’s abs will display at six-pack if they are muscular enough. this is a highly personal thing, and one person may well display the six-pack at 15%, where another would have trouble at 10%. A great six-pack is made primarily in the kitchen…not the gym.

Just my opinions though based on my own research…

I’ve also had many people tell me that they in fact feel a lot healthier when they’ve gone from too slim (10% or below), to being in the range of 15%+, especially their joints tended to feel better.

On the point of building muscle while losing fat: Yes it is indeed very possible. However, many find it more efficient (or easier) to build muscle along with a little extra fat, and then later work on losing fat. The two goals aren’t completely contradictory, but there is a small negative overlap.
It’s quite an individual thing as to the most efficient method of reaching their strength/health goals.

Well thats my two cents worth,
Cheers,
Patmanpato

@BRobert
Congraz on your achievement.

@Earl
That’s the kind of info that I don’t care about. I currently go for 1g/lbs protein, divide that by 5-6 meals, done.

@David
Nothing to add no.