Surfing, like many water sports, offers a unique opportunity to experience natural environments, yet the design of interactive technologies for water activities– “WaterHCI” – so far prioritised athletic performance over experience. To explore this opportunity, we designed SurfSync, a novel wearable system in the form of an actuating vest and a hat that provides oceanic information through sound, vibration, and heat actuation, aimed at enriching the surfing experience as a playful encounter with the ocean. We studied SurfSync in an ocean-based field study with eight surfers. Through thematic analysis of interviews, we articulated the surfers’ experiences, indicating how they made sense of playful cues while in the ocean. By reflecting on our soma design process and the surfers’ experiences, we provide six design strategies to enrich the surfing experience. Our work contributes to the emerging field of WaterHCI by providing insights into how wearables can enrich human-water experiences outdoors.

Gastrointestinal sounds are a constant part of human physiology, offering potential insights into digestive functions and everyday bodily awareness. However, these sounds are rarely noticed and often socially stigmatised, remaining underexplored in HCI despite calls to recognise the gut as a site for embodied awareness. We extend HCI’s engagement with involuntary biosignals by positioning gut sounds as a uniquely generative context for interoceptive interaction design, where systems can scaffold awareness, reflection, and care. We conducted a week-long in-the-wild qualitative study with ten participants, which showed how making gut sounds audible reshaped bodily awareness, provoked affective responses, and prompted acts of reflection and tinkering. From these insights, we contribute four bodily perspectives – Registering, Reacting, Reflecting, and Responding- that capture the oscillatory nature of interoceptive engagement and offer design strategies that position biosignals as sites of curiosity, care, and awareness that are socially situated.

Abstract Immersive virtual reality (IVR) offers new opportunities in physics education by enabling experiential learning environments, and its integration into serious games facilitates conceptual reinforcement through active engagement and situated learning. This study presents the design, iterative refinement, and evaluation of an IVR serious game for teaching projectile motion, analyzing its impact on user experience and conceptual understanding through a user- centered design (UCD) approach. The serious game was developed through two playtesting sessions involving physics professors and undergraduate students, whose feedback guided improvements in content, mechanics, and usability. A pilot study was conducted with 17 students using the Meta Quest 2 headset, and the evaluation included the Virtual Reality Neuroscientific Questionnaire (VRNQ), a perceived motivation scale, and a conceptual pre- and post-test. The iterative UCD process enhanced gameplay, immersion, and instructional clarity. Students rated the experience positively in terms of usability and motivation, while learning gain analysis showed an average normalized gain of 0.68 (Hake), a large effect size ( d = 2 . 83), and an increase in students reaching the conceptual competency threshold from 12 to 100%. These results support the potential of Parabolic Basketball VR as an immersive and pedagogically grounded educational tool, demonstrating how user-centered, iterative development can contribute to. measurable learning gains and positive user engagement, and highlighting its value as a complementary strategy for enhancing conceptual understanding in physics education.

DIS ’25, Funchal, Portugal

The field of Sports Human-Computer Interaction (SportsHCI) investigates interaction design to support a physically active human being. Despite growing interest and dissemination of SportsHCI literature over the past years, many publications still focus on solving specific problems in a given sport. We believe in the benefit of generating fundamental knowledge for SportsHCI more broadly to advance the field as a whole. To achieve this, we aim to identify the grand challenges in SportsHCI, which can help researchers and practitioners in developing a future research agenda. Hence, this paper presents a set of grand challenges identified in a five-day workshop with 22 experts who have previously researched, designed, and deployed SportsHCI systems. Addressing these challenges will drive transformative advancements in SportsHCI, fostering better athlete performance, athlete-coach relationships, spectator engagement, but also immersive experiences for recreational sports or exercise motivation, and ultimately, improve human well-being.

People with a fear of being in water rarely engage in water activities and hence miss out on the associated health benefits. Prior research suggested virtual exposure to treat fears. However, when it comes to a fear of being in water, virtual water might not capture water’s immersive qualities, while real water can pose safety risks. We propose extended reality to combine both advantages: We conducted a study (N=12) where participants with a fear of being in water interacted with playful water-inspired virtual reality worlds while floating inside a floatation tank. Our findings, supported quantitatively by heart rate variability and qualitatively by interviews, suggest that playful extended reality could mitigate fear responses in an entertaining way. We also present insights for the design of future systems that aim to help people with a fear of being in water and other phobias by using the best of the virtual and physical worlds.

Recent combinations of interactive technology, humans, and water have resulted in “WaterHCI”. WaterHCI design seeks to complement the many benefits of engagement with the aquatic domain, by offering, for example, augmented reality systems for snorkelers, virtual reality in floatation tanks, underwater musical instruments for artists, robotic systems for divers, and wearables for swimmers. We conducted a workshop in which WaterHCI experts articulated the field's grand challenges, aiming to contribute towards a systematic WaterHCI research agenda and ultimately advance the field.

Water's pleasant nature and associated health benefits have captivated the interest of HCI researchers. Prior WaterHCI work mainly focused on advancing instrumental applications, such as improving swimming performance, and less on designing systems that support interacting with technology in water in more playful contexts. In this regard, we propose floatation tanks as research vehicles to investigate the design of playful interactive water experiences. Employing somaesthetic design, we developed a playful extended reality floatation tank experience: "Fluito". We conducted a 13-participant study to understand how specific design features amplified participants' water experiences. We used a postphenomenological lens to articulate eight strategies useful for designers aiming to develop digital playful experiences in water, such as designing to call attention to the water and designing to encourage breathing and body awareness in water experiences. Ultimately, we hope that our work supports people to be playful and benefit from the many advantages of being in water.

Spectating digital games can be exciting. However, due to its vicarious nature, spectators often wish to engage in the gameplay beyond just watching and cheering. To blur the boundaries between spectators and players, we propose a novel approach called "Fused Spectatorship", where spectators watch their hands play games by loaning bodily control to a computational Electrical Muscle Stimulation (EMS) system. To showcase this concept, we designed three games where spectators loan control over both their hands to the EMS system and watch them play these competitive and collaborative games. A study with 12 participants suggested that participants could not distinguish if they were watching their hands play, or if they were playing the games themselves. We used our results to articulate four spectator experience themes and four fused spectator types, the behaviours they elicited and offer one design consideration to support each of these behaviours. We also discuss the ethical design considerations of our approach to help game designers create future fused spectatorship experiences.

Aquatic recreation encompasses a variety of water-based activities from which participants gain physical, mental, and social benefits. Although interactive technologies for supporting aquatic recreation activities have increased in recent years, the HCI community does not yet have a structured understanding of approaches to interaction design for aquatic recreation. To contribute towards such an understanding, we present the results of a systematic review of 48 papers on the design of interactive technology for aquatic recreation, drawn from the ACM, IEEE, and SPORTDiscus libraries. This review presents an aquatic recreation user experience framework that details problems and opportunities concerning water and HCI. Our framework brings us closer to understanding how technology can interact with users and the aquatic environment to enhance the existing recreational experiences that connect us to aquatic environments. We found that designers can elicit delight, enablement, challenge, and synergy in aquatic recreation experiences.