# Anthropometric Values in Spanish Elite Soccer: Differences between Divisions and Playing Positions
## 2 Materials and Methods
### Anthropometric Measurements  
Kinanthropometric measurements were taken according to the ISO 7250-1:2017 [27] and the International Society for the Advancement of Kinanthropometry (ISAK) standard [18]. The measurements taken were as follows: four basic measurements (body mass, height, sitting height, and arm span), eight skinfolds (biceps, triceps, subscapular, iliac crest, supraspanale, abdominal, thigh, and calf), three diameters (humerus, bi-styloid, and femur) and six girths (arm relaxed, arm flexed and tensed, waist, hips, thigh, and calf). The anthropometric method used to measure body weight was a SECA 862 scale (SECA, Hamburg, Germany) with 100 g accuracy. A SECA 217 detachable portable stadiometer (SECA, Germany) with 1 mm accuracy was used to measure height and sitting height; an Avanuttri wingspan meter (Avanuttri, Tres Rios, Brazil) was used to measure arm span; a CESCORF inextensible metal tape (CESCORF, Porto Alegre, Brazil) was used to measure girths; and a Slimguide caliper (Creative Health Products, Ann Arbor, MI, USA) of 0.5 mm precision was also used. All kinanthropometric measurements were measured two or three times by an anthropometrist level 1 and 2 accredited by ISAK, depending on whether the technical error of measurement (TEM) between the first two measurements was greater than 5% in skinfolds and 1% for the rest of the measurements, taking the mean or median, respectively, for subsequent analysis. The intra-evaluator TEM was 0.03% for the basic measurements, 2.24% for the skinfolds, and 0.36% for the girths, and its correlation coefficient with an expert anthropometrist level 4 was 0.99 for the basic measurements, 0.91 for the skinfolds, and 0.99 for the girths. This ensures that the data collected are as accurate and consistent as possible, which in turn guarantees the validity of the research results and allows for accurate interpretation of the differences observed between measurements. The temperature of the room where the measurements were taken was standardized at 24 \({}^{\circ}\)C, and all measurements were taken from 09:00 to 11:00.  
Body composition was determined using the equations described in the consensus document of the Spanish Group of Kinanthropometry of the Spanish Federation of Sports Medicine [15], following the four-component model (MM, FM, BM and residual mass (RM)). The following equations were used: (1) [PERSON] [28], [PERSON] [29], and [PERSON] [30] equations to calculate FM expressed in percentage; (2) [PERSON]'s equation [31] to calculate MM expressed in kg; and (3) [PERSON]'s equation [32] to calculate BM expressed in kg. At the same time, the sum of 3, 6, and 8 skinfolds was used, and adipose tissue through [PERSON]'s equation [33] as well as two health indices were calculated: waist-to-height ratio and fat distribution index. The technical errors of measurement were 7.5% for skinfolds and 1.5% for the rest of the measurements.  
Somatotype was estimated following the Heath-Carter method, establishing the three Carter components (endomorph, mesomorph, and ectomorph, separately) and representing those results in a somatotype chart. The somatotype chart is the graphical representation of the somatotype where the rating of the three components of the somatotype is plotted in a two-dimensional chart [20].