# ExRx.net

Exercise Prescription on the Net
 It is currently Fri Jan 19, 2018 8:36 pm

 All times are UTC - 6 hours [ DST ]

 Page 1 of 5 [ 66 posts ] Go to page 1, 2, 3, 4, 5  Next
 Print view Previous topic | Next topic
Author Message
 Post subject: %BF by Waist CircumferencePosted: Fri Mar 20, 2009 2:44 pm
 former lurker

Joined: Fri Mar 20, 2009 2:31 pm
Posts: 1
I noticed the following formula on the website:

LBW= 44.636 + 1.0817(wt) &SHY; 0.7396(c)

wt = Body weight (Kg)
c = Circumferences of Umbilicus Abdomen (cm)

I am not getting correct answers when I plug in numbers. Is there a part of the formula I am missing? What is the relationship between the two parts of the formula?

Thanks.
Jonathan

Top

 Post subject: Posted: Fri Mar 20, 2009 5:12 pm
 Site Admin

Joined: Tue Jun 06, 2006 11:40 am
Posts: 3991
You subtract the result of the second from the result of the first.

So the formula is this.
(44.636 + 1.0817W) - (0.7396C)=L

So you follow the order of operations. You first multiply 1.0817 by your weights in kilos. Then you add 44.636 to it. You then move over to the other set of () and you multiply your weight in centimeters by 0.7396. You should not have a number in each (). You subtract the second number form the first one. That is an rough ballpark estimate of your lean body mass.

Top

 Post subject: Posted: Mon Jun 28, 2010 3:43 am
 banned

Joined: Sun Jun 27, 2010 2:52 am
Posts: 16
Location: Banned for stupidity above and beyond the call of duty.
This body weight to waist ratio doesn't prove your fat percentage. I use accu measure calipers which you can buy online for chump change. My waist size is 35 and I weight 165 but my body percentage is 7%. I also verified this with a personal trainer.

Top

 Post subject: Posted: Mon Jun 28, 2010 6:48 am
 moderator

Joined: Sat Mar 10, 2007 5:44 pm
Posts: 6593
Location: Halifax, NS
As Ironman said, it's a rough measure. You should also keep in mind that calipers will underestimate body fat on a person with high visceral fat. I'm not saying that's your case, I expect you have a larger waist due to genetic reasons. There are a lot of variations between people that quick and easy estimating methods will, by necessity, ignore.

Top

 Post subject: Posted: Mon Jun 28, 2010 3:16 pm
 banned

Joined: Sun Jun 27, 2010 2:52 am
Posts: 16
Location: Banned for stupidity above and beyond the call of duty.
True, but isn't calipers more effective then body to waist fat percentage ratios?

Top

 Post subject: Posted: Mon Jun 28, 2010 4:03 pm
 Advanced Member

Joined: Sun Jun 24, 2007 3:46 pm
Posts: 1455
Probably depends on who's eye-balling the caliper.

Top

 Post subject: Posted: Mon Jun 28, 2010 4:20 pm
 moderator

Joined: Sat Mar 10, 2007 5:44 pm
Posts: 6593
Location: Halifax, NS
igquick wrote:
True, but isn't calipers more effective then body to waist fat percentage ratios?

I never said waist measurement was better, just that neither is perfect. Frogbyte is right, it depends on the user. Either way, it's a guideline and it's the changes that matter.

Top

 Post subject: Posted: Mon Jun 28, 2010 4:43 pm
 banned

Joined: Sun Jun 27, 2010 2:52 am
Posts: 16
Location: Banned for stupidity above and beyond the call of duty.
I never claimed that you said that waist measurement was better, I was just asking.

Top

 Post subject: Posted: Mon Jun 28, 2010 11:04 pm
 Advanced Member

Joined: Tue Nov 17, 2009 1:44 am
Posts: 1122
In general, calipers are a good method.

I have had them done on me a lot when I did competetive sports requiring weighins. Good trainers will be very repeatable and correlate well to each other. you have to know how to measure for the right spot and get a good pinch. 6 spot Yahazs (sp?) method is what I have done at the YMCA by the phys therapist wannabe. It's great. I don't even pay anything. Just chat him up. gonna help him with some chemistry tutoring if he needs it.

Leigh Peele has a good video on bf methods and fat patterning in men/women. Very illuminating.

Top

 Post subject: Posted: Tue Jun 29, 2010 12:58 am
 banned

Joined: Sun Jun 27, 2010 2:52 am
Posts: 16
Location: Banned for stupidity above and beyond the call of duty.
I use accu measure and sometimes a trainer with calipers for free but I have to pretend Im taking a PE class. Thats cool that you get it for free, because trainers that get your fat percentage costs money.

Top

 Post subject: Posted: Tue Jun 29, 2010 4:06 am
 Site Admin

Joined: Tue Jun 06, 2006 11:40 am
Posts: 3991
One caveat with calipers. If you have loose skin, it will measure you low.

Top

 Post subject: Posted: Tue Jun 29, 2010 10:34 am
 banned

Joined: Sun Jun 27, 2010 2:52 am
Posts: 16
Location: Banned for stupidity above and beyond the call of duty.
I don't have loose skin, unless I was fat when I was younger, then suddenly lost a significant amount of body weight.

Top

 Post subject: Posted: Tue Jun 29, 2010 1:31 pm
 Advanced Member

Joined: Tue Nov 17, 2009 1:44 am
Posts: 1122
Ironman wrote:
One caveat with calipers. If you have loose skin, it will measure you low.

Great insight. Relevant to me. I lost a lot of fat, very rapidly and have some of this. Hmm. Maybe I should get a Dexa.

This would imply that I could take my weight significantly lower. I'm at 165 and 10%. I've been suspecting this is shaded low, despite the (I think) skill of calipers (based on pervious eperience when younger and this fellow being pretty exacting). I didn't want to go much under 10% given my age and a desire to build muscle. But maybe I could safely go down to 160 or even 155 and still keep needed fat levels for hormones and all that.

Hmmm. Dexa is only 200 bucks.

Top

 Post subject: Posted: Wed Jun 30, 2010 2:15 am
 Site Admin

Joined: Tue Jun 06, 2006 11:40 am
Posts: 3991
ApolytonGP wrote:
Ironman wrote:
One caveat with calipers. If you have loose skin, it will measure you low.

Great insight. Relevant to me. I lost a lot of fat, very rapidly and have some of this. Hmm. Maybe I should get a Dexa.

This would imply that I could take my weight significantly lower. I'm at 165 and 10%. I've been suspecting this is shaded low, despite the (I think) skill of calipers (based on pervious eperience when younger and this fellow being pretty exacting). I didn't want to go much under 10% given my age and a desire to build muscle. But maybe I could safely go down to 160 or even 155 and still keep needed fat levels for hormones and all that.

Hmmm. Dexa is only 200 bucks.

In the picture I saw you looked like you had similar bodyfat % and amount of loose skin as I do. I was fatter than you, but I've gained more muscle too. That helps take up some of that skin. Calipers show me at about 10%, but I'm probably more like 15.

If you get an impedance machine with an "athlete" mode on it, it may be accurate for you. I've gotten far too big for it, so mine measures me high.

Top

 Post subject: Posted: Wed Jun 30, 2010 12:08 pm
 Advanced Member

Joined: Tue Nov 17, 2009 1:44 am
Posts: 1122
Impedance is crap. I'm going to get dexaed.

Top

 Display posts from previous: All posts1 day7 days2 weeks1 month3 months6 months1 year Sort by AuthorPost timeSubject AscendingDescending
 Page 1 of 5 [ 66 posts ] Go to page 1, 2, 3, 4, 5  Next

 All times are UTC - 6 hours [ DST ]

#### Who is online

Users browsing this forum: Yahoo [Bot] and 2 guests

 You cannot post new topics in this forumYou cannot reply to topics in this forumYou cannot edit your posts in this forumYou cannot delete your posts in this forumYou cannot post attachments in this forum

 Search for:
Powered by phpBB® Forum Software © phpBB Group