I find it mildly amusing that almost everyone that gets a BMI of over 25 starts claiming they are all muscle, and have 3-4% body fat.
In general the BMI is an excellent descriptor for the vast majority of us.
It certainly has it's disadvantages, no one disputes that. But it's likely that for the majority of AT it would be quite accurate IMHO.
Body Mass Index (BMI)
BMI is a reliable indicator of total body fat, which is related to the risk of disease and death. The score is valid for both men and women but it does have some limits. The limits are:
It may overestimate body fat in athletes and others who have a muscular build.
It may underestimate body fat in older persons and others who have lost muscle mass.
FWIW, my BMI is 18.2, which puts me in the underweight category just below the bottom of the normal category.
Personally, I'm not terribly muscular for the most part and am quite possibly have less muscle mass then most men my height/weight/age. What muscle I do have is most likely predominantly in my lower body, in my upper body I'm well aware then I am likely relatively 'weak'
Most everyone I know considers me under-weight, though on a personal level I'd still like to lose about 14-19lbs.
I tend not to eat very much though on the rare occasion I'll splurge.
I consider my self reasonably fit and generally quite active.
I run 6-8 miles every other day, and avidly play soccer relatively often.
I have an unfortunate tendency to gain weight pretty quickly, in the past when I've cut down my running I've generally quickly jumped up to 150-160lbs.
I've been trying almost constantly for years to break through 130lbs, but I've been quite unsuccessful. I've pretty much come to the conclusion that 130lbs is the low point I'm capable of.
Presntly I weight 134lbs, and am 6'0 tall.