BMI Question - Exercise & Fitness Message Board

dgconner154 · 12-12-2004, 03:31 PM

I am a 28 year-old male, 5'-10" and approx. 175 lbs. I have been working out for about 2 years and have seen good results, but recently (past 6 weeks or so) I have been traveling alot for work, holidays, etc, and have neglected my gym routine. In that time I have probably put on a couple pounds, and out of curiousity I checked my BMI with several on-line calculators. They all tell me I have a BMI of 25.1, which qualifies as overweight. I have some slight mid-section fat, but really not too much. What really freaked me out, though, is that "normal" is 18.5 - 24.9. In order for me to be at 18.5 I would need to weigh 129 lbs. How can this be normal? I can't imagine that a 28-year old guy who is 5'-10" and weighs 129 lbs is normal or even all that healthy? I know BMI is generalized and isn't necessarily a perfect indicator of fitness, but this seems odd. In order for me to fall right in the middle of "normal" (BMI = 21.7) I would need to weigh 151 lbs. This still seems awfully light.....Any thoughts?

never2L8 · 12-12-2004, 04:31 PM

BMI is a very general indicator and makes no allowance for a persons build - anyone with only a reasonable amount of muscle usually shows up as overweight. I am in the obese category at 5'10" and 220lb and while I agree I am overweight, I haven't been in the BMI healthy range since I was about 15.

A check on a few sites advises that the BMI is not accurate for muscular people or those with "large skeletal structure". I would use other factors to asses your health like cholesterol levels, aerobic capacity, body fat measurement, waist to hip ratio etc.

dgconner154 · 12-16-2004, 08:53 PM

Thanks for the info...I have used a Tanita scale at my gym and also used the method of measuring waist, hips, arms, etc. Both methods indicate 8.5% - 9.5% body fat, but I'm not sure how accurate either one is. I've heard Tanitas aren't very accurate...Either way I guess thats probably a better indication than BMI??

Tank53 · 12-17-2004, 07:54 AM

BMI as someone indicted is a good, overall, general use way of checking people's fat %. However, I've found its not very good at being accurate with athletes. Its used for kind of run-of-the-mill American.

So for me, its tells me I'm gonna die by tomorrow almost. 240 lbs at 5'10" I know that isn't all skin, bone, and muscle...I'm sure there's a good amount of insulation. But during school when we used calipers to measure fat, I was at about 12% bf. Now if I used the BMI for me currently, it would tell me something like 33% bf. I know I'm not small but I'm not Fat Albert either.

Sometimes you just gotta throw BMI out the window. Its a joke to me anymore. For most women though its a good tool.

I don't know what to suggest to check body fat. There's electro-static kind (I believe thats what its called). My gym uses it and I've always thought the one they had was junk. I think Naxis suggested several different types. Try calipers for the fat and maybe use measuring tape if you're watching what you're losing. I've always found the measuring tape around the stomach is a good way to see how fat I've gotten.

I'm sure you could do a search on these boards and find plenty of answers about it.

ChappyBoy · 12-20-2004, 08:35 AM

Bmi is least accurate -

Elctrostatics is also quite poor and has many influencing factors.

Calipers with a wel trained individual have a +-2% accuracy

Hydrostatic dunk tank is most accurate but not everyone has one of these lying around. I used one when I was working on my masters - quite fun