‘an investigation into the body fatness size and shape using healy and tanner’s method (nhanes...
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Results
Healy and Tanner method example with 3 boys with visually similar body sizes but different body shapes
A B C A B C
A B C A B C
A B C
Example dataset
Arm
Waist
Thigh
Calf
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20
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15
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Arm
Waist
Thigh
Calf
20
20
10
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20
10
15
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15
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- -
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+ +
- -
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- -
+ +
+ +5
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-5
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-5
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Step 1: measure all the body parts using same tool and standard Step 2: to get size, calculate averages of each individual’s measurements
Step 3: to get shape, calculate the differences between the average (size) and each measurement
A’sSize
B’sSize
C’sSize
Name (ID) Size Shape 1 Shape 2 Shape 3 Shape 4
A 15 0 0 0 0
B 15 -5 5 5 -5
C 15 5 -5 -5 5
Arm
Waist
Thigh
Calf
A B C20
20
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15
Background & Purpose
Previous studies have shown that both size and shape of fatness independently associated with various non-communicable diseases such as type-2 diabetes and stroke. This means that not only bigger fatness but also more centralised fatness (e.g., abdominal obesity) increase the risk of diseases. Due to the reason, some researchers combined traditional fatness estimators such as body mass index (BMI) and waist to hip ratio (WHR) to increase the statistical relationship. However, it was pointed that the combination of the traditional fatness estimators is not recommended due to high correlation between the estimators. Thus, more direct fatness measurement and statistical method that divides size and shape is employed in this study.
Purpose of the study: the objective of this paper is to identify the trends of body fatness size and shape among the U.S population using the National Health and Nutrition Survey (NHANES) III dataset.
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2119 201816 171513 141210 1197 8
7573 747270 716967 686664 656361 626058 595755 565452 535149 504846 474543 444240 413937 383634 353331 323028 292725 262422 232119 201816 171513 141210 1197 864 53
7573 747270 716967 686664 656361 626058 595755 565452 535149 504846 474543 444240 413937 383634 353331 323028 292725 262422 232119 201816 171513 141210 1197 864 53
Non-Hispanic White Non-Hispanic Black Mexican-American
Non-Hispanic White Non-Hispanic Black Mexican-American
Natural Log*
Age
BMI
Age
Age
Graph 1. Fatness size and shape of males and females
Graph 2. Fatness size and shape of Non-Hispanic White, Non-Hispanic Black, and Mexican-American males
Graph 3. Fatness size and shape of Non-Hispanic White, Non-Hispanic Black, and Mexican-American females
Reference: Healy, M.J.R. & Tanner, J.M., 1981. Size and Shape in Relation to Growth and Form. Symp. Zool. Soc. Lond., 46, pp.19–35
(Size)
(Shape)
Size Triceps Subscapular Suprailiac Thigh
Size Triceps Subscapular Suprailiac Thigh
Male Female Size(Average)
Triceps shape(Residual)
Subscapular shape(Residual)
Suprailiac shape(Residual)
Thigh shape(Residual)
Male Female
Size(Average)
Triceps shape(Residual)
Subscapular shape(Residual)
Suprailiac shape(Residual)
Thigh shape(Residual)
Non-Hispanic White Non-Hispanic Black Mexican-American
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The fatness shape and size of the US population (3-75 years old) : NHANES III
Hankook Kim, Dr Emily Petherick, and Dr Ines Varela-Silva School of Sport, Exercise, and Health Department, Email: [email protected] Loughborough University, UK
Method
Dataset: NHANES IIIThe NHANES III dataset was thought to be ideal to investigate the fatness size and shape of different gender and ethnic background because: 1) the dataset is representative data of U.S population (33,994 individuals), 2) includes 4 most commonly used skinfolds (e.g., triceps, subscapular, suprailiac, and thigh skinfolds).
Statistical method: Healy and Tanner (1981)The method of Healy and Tanner was first published in 1981 and is a viable alternative way to evaluate overall fatness (size) and regional fat distribution (shape) together. The method was designed because physical outline develops not only its size but also the shape at the same time. The method statistically divides data of a single physical outline into uncorrelated size and shape data by means of principal component analysis and subsequent use of the residual values.
* Natural log: all the measurement values were transformed into natural log for stable normality of distribution and constancy of variance.
Natural Log*
Natural Log*
Discussion
1. The fatness size and shape trends of male and female were different. Graph 1 and 1 shows that the shape trends flips. Males younger than 12, the shape scores of extremity (triceps and subscapular) was higher than centre (suprailiac and thigh), but males older than 16 showed the opposite.2. BMI does correlate with fatness size and shape of older people aged over 20, but does not correlate with younger people’s (under 20 years old).3. Partial ethnic characteristics were found. Most consistent characteristics were: 1) Non-Hispanic Black males had smaller fatness size than the other two male ethnic groups. 2) Both non-Hispanic white males and females had more extremely shaped fatness, which also means that they had relatively less centralized fatness ( & ) . 4. Major limitation of the study is that this method only considers fatness, but not other body characteristics such as frame, fat free mass and etc. In addition, Healy and Tanner method does not allow any missing data. Thus, a vast amount of data was excluded (8,905 out of 34,995 persons).5. In the future, studies which adjust fatness size and shape by body frame and more detailed analysis on the shape differences of male and female are needed.