In many applications, such as car seats and clothing, the softness of the human body affects how it interacts with the garment or seat, and thus comfort. Therefore, modelling this body softness is necessary and needs to be validated to demonstrate comparable effects to those observed in experiments, in order to determine its usability. 4D scanning is a technology that captures body deformations, making it a promising tool for validating body deformations and interactions. In this research, 4D scan data is used to improve the validation of models, particularly finite element (FE) models, by identifying comparable motion states and comparing body deformations. Deformable FE models of the human body are developed for static and dynamic analysis applications, such as individual bra fit analysis. 4D scan data is used to improve model validation by developing automatic analysis methods for 4D scan data to select comparable body states, which are then used to validate the models. Three methods for improving model validation are presented.