# Predicting User's Measurements without Manual Measuring: A Case on Sports Garment Applications
## 2 Materials and Methods
### Procedure  
First, personal information in the form of four basic parameters was requested from the participants: age, gender, weight, and height.  
Second, the chest, waist, and hip circumferences of the participants were roughly measured in normal clothes, in order to select a cycling outfit (pants and shirt) based on the existing size charts from Bioracer (see Figure 1). A set was given to the participant in the supposedly ideal size. Each participant was allowed to try all other outfit sizes in order to determine their optimal fit according to personal preference. In addition, a validation was done on the stretch, using the grid pattern on the outfit. In order to analyze the optimum fitting outfit according to the design rules of Bioracer, it was necessary that as few wrinkles as possible occurred in the worn outfit. Thus, a minimal stretch over the entire outfit was aimed for, while keeping the outfit comfortable for the subject throughout the test. As a consequence, for the further course of the experiment, some participants received a smaller sized clothing to wear in comparison to their supposedly or preferred optimal size.  
Third, in addition to the offered outfit, the preferred sizes of the cycling pants and shirts that would have been handpicked by the participants were also noted.  
Figure 2: Custom made research garments in the standard confection sizes. The custom print consists of a 1 \(\times\) 1 cm grid of lines that aid in 3D scanning and measuring of stretch.  
Fourth, based on common measurements that can be found in the WEAR database as well as the shape model, eighteen manual measurements were conducted on the participant wearing the cycling outfits: arm length, shoulder breadth, chest circumference, circumference under bust, hip circumference, waist circumference minimum, waist front length, acromion shoulder breadth, armscye circumference, biceps circumference, chest girth, hip breadth sitting, mid lower arm circumference, neck base circumference, spine to shoulder, tight neck circumference, waist circumference 'at pants height', and wrist circumference. Measurements were done by one and the same trained researcher, to ensure accurate measurements [36]. Anatomical landmarks and measurement methods were followed as described in the CAESAR report [15]. These values were used as reference in this study to compare all predicted measurements with. All measurements were taken in order, twice in a row, and in case of a notable offset in both measurements, a third time to eliminate measuring or typing errors [36]. For the measurements used in the Bioracer sizing table, the closest corresponding Caesar equivalents are used, namely, the maximum hip circumference, the minimal waist circumference, and the chest circumference over bust.  
Fifth, wearing the outfit of the second step, two 3D scans with the Styku scanner were taken one after the other. Two scans were used to compare the outcome of both, and, in case of obvious variation in the data, a third scan was taken as validation (this could occur when subjects moved throughout the scanning process). By wearing the cycling jersey, a smooth (wrinkle-free) surface was achieved for the scan, and accurate measurements could be achieved. Based on these 3D scans, 28 measurements of the participant were recorded (for a complete list, see [28; 30]).