Study B2 is a single-centre observational, non-significant risk, training data collection study that aims to collect lower limb activity data using commercial inertial measurement units (IMUs) from healthy volunteers while performing physiotherapy exercises. In parallel cameras will be used to record the activity of the lower limbs. The collected data will be used to inform an extended reality environment (XR) and a serious game for the empowerment and guidance of post-operative patients in the clinical ward to perform their prescribed physiotherapy exercises for the prevention of DVT. Activity data will be recorded with commercially available sensors placed at specific positions of the lower limbs and commercially video cameras placed in still positions in the room. Recorded data will be anonymized and videos will only record views from below the pelvis. This document describes in detail the steps to be followed for recording the activity data from healthy volunteers while performing the physiotherapy exercises.