Since 1980, researchers have been exploring various capture technologies and tracking methods to reconstruct the 3D segmental motion of the submerged body (Gourgoulis et al., 2008, Monnet et al., 2014, de Jesus et al., 2015, Veiga et al., 2022). However, accurately estimating such kinematics remains a challenge, mainly because swimming is a complex, dynamic activity that involves simultaneous air and underwater motion. To track the motion of swimmers, researchers have leveraged the experience gained from motion capture analysis, using body reflective markers with optoelectronic systems (Gourgoulis et al., 2008). However, despite traditional laboratory camera setups, surveying the swimmer’s motion requires additional water-proof submerged equipment to protect the cameras (Silvatti et al., 2012) and to perform the camera calibration (de Jesus et al., 2015). In order to track the full swimmer movement, the two different working volumes must be joined into a unique calibration volume (Shortis, 2015). Qualisys has one system, (Sweden, Oqus3＋ underwater), specifically designed for underwater swimming analysis. Nonetheless, it is very expensive, making it inaccessible to many researchers and swim teams. More affordable and scalable techniques, such as lower-cost motion capture systems, have been investigated, especially demonstrating the potential of action sports cameras (ASC). Since 2012, our group has been testing video-based systems and developing custom methodologies for enabling 3D kinematics analysis of swimmers. Special focus was on calibration procedures to increase the accuracy in underwater acquisitions (Silvatti et al., 2012, Silvatti et al., 2013), motion tracking of underwater markers using ASC (Bernardina et al., 2017, Bernardina et al., 2019a), and acquisition of human kinematics in large working volumes using moving ASC framework (Bernardina et al., 2019b). Such studies were focused mainly on the feasibility of 3D kinematic analysis underwater. Actually, the swimmer stroke is a complex arm movement that develops in the air as well. Thus an extended acquisition setup is necessary and concurrent calibration of both in-air and underwater is required. As such, the present work aimed at verifying the reliability of an air-underwater acquisition setup and an innovative technique for calibrating the overall working volume. The approach was experimented with by verifying the feasibility of hand motion reconstruction of swimmers during the front crawl stroke cycle and testing the smoothness of the in-air/underwater transition. To the best of our knowledge, the current study is the first that analyzed these points and the full swimming stroke cycle.