# Application of Artificial Neural Network to Somatotype Determination
## 2 Materials and Methods
### Study Design
#### 2.1.2 Measurement Techniques  
Ref. [39]. Height (H). Height was taken with the subject standing straight, against an upright stationmeter, touching the device with heels, buttocks and back. The head was oriented in the Frankfort plane (the upper border of the ear opening and the lower border of the eye socket on a horizontal line), and the heels together. The subject was instructed to stretch upward and to take and hold a full breath.  
Body weight (BW). The subject, wearing minimal clothing (underwear is recommended), stands in the center of the scale platform. A correction was made for clothing so that nude weight could be used in subsequent calculations.  
Skinfolds. A fold of skin and subcutaneous tissue was raised firmly between the thumb and forefinger of the left hand and away from the underlying muscle at the marked site. The edge of the plates on the caliper branches was applied 1 cm below the fingers of the left hand and they were allowed to exert their full pressure before reading at 2 s the thickness of the fold. All skinfolds were taken on the right side of the body. The skinfolds were taken from the subject standing relaxed, except for the calf skinfold, which was taken with the subject seated.  
Triceps skinfold (TS). With the subject's arm hanging loosely in the anatomical position, the fold at the back of the arm at a level halfway on a line connecting the acrom and the olecranon processes should be raised.  
Subscapular skinfold (SubS). The subscapular skinfold on a line from the inferior angle of the scapula in a direction that is obliquely downwards and laterally at 45 degrees should be raised.  
Supraspinale skinfold (SuprS). The fold 5-7 cm (depending on the size of the subject) above the anterior superior iliac spine on a line to the anterior axillary border and on a diagonal line going downwards and medially at 45 degrees was raised.  
Medial calf skinfold (CS). The vertical skinfold on the medial side of the leg, at the level of the maximum girth of the calf was raised.  
Biepicondyl breadth of the humerus, right (HB). The width between the medial and lateral epicondyles of the humerus with the shoulder and elbow flexed to 90 degrees was measured.  
Biepicondyl breadth of the femur, right (FB). The subject was seated with the knee bent at a right angle during the measurement. The greatest distance between the lateral and medial epicondyles of the femur was measured.  
Upper arm girth (AG). The right elbow was flexed and tensed. The subject flexed the shoulder to 90 degrees and the elbow to 45 degrees, clenched the hand, and maximally contracted the elbow flexors and extensors. The measurement was taken at the greatest girth of the arm.  
Calf girth (right calf) (CG). The subject stood with feet slightly apart. The tape was placed around the calf and measured the maximum circumference.  
The stature and girths to the nearest mm, biepicondyl diameters to the nearest 0.5 mm, and skinfolds to the nearest 0.1 mm (Harpenden caliper) were read. The measured sites were marked and the complete sequence repeated a second time. For further calculations, the duplicated measurements were averaged.  
The individual anthropometric somatotypes were calculated for components--endomorphy (Endo), mesomorphy (Meso), ectomorphy (Eto) by entering the data into equations, according to [PERSON] and [PERSON] [39]:  
\[\text{Eto}=\frac{\text{H}}{\text{BW}^{\frac{1}{3}}}, \tag{1}\]  
where H is the height [m], BW is the body weight [kg]  
\[\text{Endo}=-0.7182+0.1451\text{X}-0.00068\text{X}^{2}+0.0000014\text{X}^{3}, \tag{2}\]  
where:  
\[\text{X}= \tag{3}\]  
Meso \[=\] [0.858 HB + 0.601 FB + 0.188 AG (corrected) + 0.161 CG (corrected) ] - (0.131 H) + 4.50 (4)  
BMI was calculated as \(\text{BW}/\text{H}\) (kg/m\({}^{2}\)) [40]. BMI was categorized according to the World Health Organisation (WHO) [41]; 7% of women had normal body weight, whereas 13% were classified as underweight and 11% as overweight and obese (data not shown).