SUBJECT NAME: EMMAE THALEEN ARINJAMAL
A.
AGE: 20
GENDER: FEMALE
Height = 156 cm
B.
Weight = 50 kg
C.
BMI = height ( m 2 ) = =20.55 kgm-2 (1.56 m ) 2
D.
Determination of body fat
weight ( kg )
50 kg
1. Skin fold measurement i. ii.
Biceps = 5 mm Triceps = 22.2 mm
iii.
Subscapular = 14 mm
iv.
Suprailiac = 15.8 mm
v.
Thigh = 12.8 mm
a. Using Using genera generaliz lized ed body compos compositi ition on equatio equations ns Body Density = 1.1599 – 0.0717 x (log ε ) = 1.1599 – 0.0717 x (log 69.8) = 1.0277 Where
ε
= sum of the triceps, subscapular, suprailiac and biceps skinfolds
Brozek equation: Percent body fat = (457/body density) – 414 = (457/1.0277) – 414 = 30.6823 Siri equation
: Percent body fat = (495/body density) – 450 = (495/1.0277) – 450 = 31.6581
b. Using sum of four skin folds
Sum of four skin folds (Biceps, Triceps, Subscapular, Suprailiac) = 5 mm+ 22.2 mm+ 14 mm + 15.8 mm = 57 mm From nomogram, Percent Body Fat = 29.1 % 1
2. Omron Body Fat Analyzer Percent of body fat : 28.4 %
E.
Mass of body fat : 14.2 kg
Circumference Measurements Waist Circumference: 71 cm
Hip Circumference: 89 cm Waist – Hip Circumference Ratio: 0.7978 Healthy (< 0.8)
F.
Assessment Fat Free Mass Mid Upper Arm Circumference: 250 mm Mid Upper Arm Muscle Circumference (MUAMC) = Mid-upper-arm circ.(C1) – ( π x TSK) = 250 mm- ( π x 22.2 mm) = 180.26 mm Where TSK = triceps skinfold thickness Arm Muscle Area=
[C − (π ×TSK ) ] 2 4π
=
(180 .26 ) 2
= 25520.47 mm2
4π
where C = mid-upper-arm circumference Age/ sex percentile values for arm muscle area = 75th percentile
This subject has a normal BMI of 20.55 kgm -2 . In determination of body fat according to three different techniques: using generalized body composition equations, sum of four skinfolds and Omron body fat analyzer, this subject is categorized under the same category that is the upper end of acceptable range. There is a different percentage of body fat when using generalized body composition equations (Brozek and Siri equations) and sum of four skinfolds in which they are differ by 1-2%. This could be caused by some error while doing skinfolds measurements. Skinfolds measurements are easy, quick and inexpensive to determine body fat however this method is easily contribute to error. The site selection and technique in placing and reading the caliper must be handle carefully. Repeated measurements (reading) can reduce error. Even though this subject has normal BMI, but it has high percentage of body fat as categorized in the upper end of acceptable range (24-31%). This indicates that she has a high body fat composition for her height and weight. 2
From the observations above, this subject has normal BMI, with upper end of acceptable range for percentage body fat, circumference measurements in the healthy range, and average muscle content.
Do we need to change BMI cut off for Asian?
. Obesity is recognized worldwide as a serious health problem. Recent reports have shown that Asian countries are no exception. Therefore, BMI cutoff points are used to define overweight and obesity in any range. Body mass index (BMI; in kg/m2) is widely recognized as a weight-for-height index that has a high correlation with adiposity, but it does not quantify total body adiposity or convey information concerning regional fat distribution. BMI is useful in comparing data from different studies and countries. BMI cutoff points should be considered as a guide to allow for the comparisons among various populations and over time. Currently, the National Institutes of Health, Healthy People 2010 , the 2000 Dietary Guidelines for Americans , and the WHO all use similar cutoff points of BMI for defining overweight (BMI ≥ 25.0) and obesity (BMI ≥ 30.0). A report cosponsored by the WHO Western Pacific Region recently recommended different ranges for classifying overweight and obesity for populations within the Asia-Pacific region. Increases in health-related risk factors and co morbidities associated with obesity occur at a lower BMI in Asian populations than in other ethnic groups. By contrast, Pacific Islanders appear to be more muscular and have comparably lower levels of body fat at a given BMI. On the basis of the respective health-related risk factors and co morbidities in these populations, lower cutoff points for Asians were identified for overweight (BMI ≥ 23.0) and obesity (BMI ≥ 25.0) and higher cutoff points for both were suggested for Pacific Islanders (BMI ≥ 26 and BMI ≥ 32, respectively). An extension of the rationale used in developing this regional WHO report could be applied to subpopulations within other countries. In the United States, the health-related risks associated with obesity are commonly observed in Japanese Americans at lower BMIs than in whites, whereas, black Americans have been shown to have fewer health-related risk factors than do whites at a given BMI. The difference in health-related risk factors among various ethnic populations may be explained by data related to body fat distribution, including relative amounts of visceral adiposity or intraabdominal fat. The fact that BMI does not provide information concerning fat distribution re-emphasizes the concept that the BMI cutoff points should serve as guidelines and further assessment and characterization should be performed as needed. In conclusion, we need to change BMI cut-offs for Asians since such individuals have different associations between BMI, percentage of body fat, and health risks from other ethnic groups.
National Institutes of Health. Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults—the evidence report. Obes Res 1998; 6:51S–209S. World Health Organization. Report of a WHO Consultation on Obesity. Obesity: preventing and managing the global epidemic. Geneva: World Health Organization, 1998. 3
US Department of Health and Human Services. Nutrition and overweight. In: Healthy People 2010 (conference edition). Washington, DC: US Government Printing Office, 2000. US Department of Agriculture and US Department of Health and Human Services. Nutrition and your health: dietary guidelines for Americans. 5th ed. Washington, DC: US Government Printing Office, 2000. (Home and Garden Bulletin no. 232.) Health Communications Australia Pty Limited, 2000. The Asia-Pacific perspective: redefining obesity and its treatment. World Wide Web: http://www.idi.org.au/obesity_report.htm (accessed 21 August 2000). National Task Force on the Prevention and Treatment of Obesity. Overweight, obesity and health risk. Arch Intern Med 2000; 160: 898–904.
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