Kinanthropometry application of depth camera based 3D scanning systems in cycling : repeatability and agreement with manual methods

Recent literature suggests that 2D and 3D anthropometric measures are better predictors of sports performance, than traditional 1D measures. The emergence of 3D scanning systems offers a cheap, easy and effective method of estimating these measures. Therefore the aim of this study was to investigate the repeatability of a depth camera based 3D scanning system, and its agreement with manual methods in the extraction of simple thigh measurements. Using 15 healthy, recreationally active male participants, five measurements of the thigh (upper thigh circumference, mid-thigh circumference, knee circumference, knee to mid-thigh length and mid-thigh to upper thigh length) were taken using an anthropometric tape measure and digital callipers, and scanned using a 4-camera Kinect based 3D scanning system (using custom analysis software). Agreement and repeatability was subsequently determined. This study demonstrated a low cost Kinect-based 3D scanning system is capable of extracting length and circumference measures within ~2% and ~3-4%, respectively, with high repeatability, technical error measurements (TEM) of ~1.80% and ~0.7% respectively. The 3D scanning system was able to measure the thigh in good agreement with manual measurement methods, with the presence of systematic bias in circumference. Whilst maintaining a very high degree of repeatability, suggesting it is a suitable method to extract simple thigh measurements.