Wednesday 110309

Workout

2000m Row or 1M Run
30-Box Jumps
30-Ring Push-ups
1000m Row or .5M Run

TitanFit Trainers WOD
PART 1 (for time):

50 Wallballs (20#/14#) plus
3 ROUNDS:
30 Double Unders;
15 Toes to Bar;
10 Front Squats (135#/95#)

PLUS (IMMEDIATELY FOLLOWING)

PART 2 (max weight):

1 Rep Max Clean (3 MINUTE TIME LIMIT)

My from obese to “normal”…OK it was not a journey, just a new measure of body adiposity recently developed.  Give the following a read and see where you fall.

New measure of obesity – body adiposity index (BAI)

Scientists have proposed a new method for determining body fat, called the Body Adiposity Index.

Background

Obesity affects 500 million people world-wide (which is crazy when one billion people are starving, but we’ll leave that issue for another time.)

There are several methods for measuring body fat (including hydrodensitometry, calipers, DEXA – Dual Energy X-ray Absorptiometry, infrared, MRI, and so on. See Body Fat Analyzing for more information.)

But is there an easy, low-tech way to measure whether somebody has a healthy amount of body fat, or is overweight?

For almost 200 years, the Body Mass Index (BMI) has been used to give a measure of body fat. The calculation for BMI is as follows.

$\text{BMI}=\frac{\text{height in m}}{\text{(weight in kg)}^2}$

BMI is useful in that you only need to know the person’s height and weight.

The problem with the BMI is that it often fails as a measure of how much unhealthy fat you are carrying. There are broad ranges in the BMI for “healthy” and “obese” to allow for athletes (who tend to be muscular, and muscles are more dense than fat) and women (who tend to have more body fat). The BMI overestimates body fat in lean people.

Also, you need a reliable set of scales to use the BMI.

In short, we need a new way to measure obesity.

Ressearcher Richard Bergman of the University of Southern California measured 1700 Mexican-Americans for their fat levels and has recently proposed a new index – Body Adiposity Index (BAI). The formula is as follows:

$\text{BAI}=\frac{\text{hip (in cm)}}{\text{height (in m)}\times\sqrt{\text{height (in m)}}}-18$

The “hip” measurement is actually around your belly button level (which is usually a maximum).

Applying some basic index laws (fractional exponents), we can express this as:

$\text{BAI}=\frac{\text{hip in cm}}{\text{(height in m)}^{1.5}}-18$

Bergmean’s team settled on this formula after cross-checking the subjects’ body weight using Dual Energy X-ray Absorptiometry, mentioned earlier.

One advantage of the BAI is it doesn’t depend on weight – just 2 simple length measurements.

More research needs to be done (it has not been extended to caucasians yet) before it will be considered a valid measure of body fat.

I developed a new online calculator where you can find your own BAI and compare it to your BMI.

Try it out and let me know what you think. Go to:

Comparison calculator: BMI – BAI

Final note – is it really complex?

The reporter from Reuters appears to have been a math phobe. At one point the article said:

BAI is a complex ratio of hip circumference to height that can be calculated by doctors or nurses with a computer or calculator.

Complex? Really? It’s rather sad when grade 8 index laws are considered “complex”. And I imagine most people would use a calculator (or an online tool, or a chart) to calculate their BMI. I don’t regard the BAI as all that more difficult in this respect.

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1. Anders says:

13:33 on the row-box jump-push-up-run WOD. Felt strong.

I’m not positive on my hip measurement, but apparently I am very normal in BMI but am quite underweight as far as the BAI goes. Not sure I trust anything that only takes into account two measurements of your body composition. How about this: my ideal weight is the amount I need to be to post the best times and the heaviest lifts I can. I’ll let the scale figure out whatever that number is.

18:53. I can’t rep out the box squats nor run as fast as Anders. I had to work hard to keep Sloan from beating me. Fun WOD

3. Sloan says:

18:57… almost got Herb!

4. Newge says:

18:10

5. Nail says:

13:59

6. Anders says:

Jess – 21:30 (ring push-ups on knees). Ring push-ups took about 4-5 minutes alone.