Although immersive technologies hold enormous potential for enhancing sports training, existing systems encounter notable limitations. While fully immersive virtual reality (VR) systems can address constraints of physical training setups such as limited space or equipment, full VR environments often lack rich, realistic, and multisensory feedback often required for effective sports training. To address this gap, this work investigates skill-based sport training, particularly, golf putting, across the reality-virtuality continuum. We implemented a mixed reality (MR) putting simulator that combines real equipment (putter and golf ball) with a virtual training environment. Three training conditions were realized: (i) real-world putting, constrained by limited physical space; (ii) a VR putting, in which a real putter and ball are used but represented virtually within the virtual environment (VE); (iii) an augmented virtuality (AV) putting, which reveals the real putter, ball, and users' limbs through a localized video-passthrough window, aiming to preserve users' sense of embodiment and presence while enabling simulation of an unlimited putting area. We conducted a pilot within-subjects experiment with 36 participants and found that the AV condition improved immediate putting performance, reduced task load, reduced perceived motion sickness, and increased user preference compared to the VR condition, while user's sense of presence remained comparable to VR training. These findings indicate that AV offers a pragmatic "sweet spot" on the virtuality continuum, balancing the tradeoff between sensory fidelity and training flexibility, offering valuable design insights for immersive sports training systems.

While consumer-grade virtual reality (VR) hardware can deliver immersive audiovisual experiences, these systems often lack the ability to display realistic haptic feedback, or incorporate cost-efficient vibrotactile actuators with very limited abilities to provide tactile feedback. To overcome these limitations, we introduce an approach based on audio-based vibrotactile actuators. Due to their wide frequency response and multiple resonant frequencies, they can provide more tactile details. In our implementation, every VR interaction uses standard audio clips to provide simultaneous auditory and tactile feedback, as well as coupled realistic physics simulations for the visual feedback. We evaluate our approach to assess the benefits on the user’s experience regarding various interaction scenarios in VR, comparing our approach to a simulated fixed-frequency actuator as a baseline. The results confirmed the benefits of our approach in terms of user preference, perceived realism, comfort, sense of agency, and texture perception. Furthermore, multimodal feedback resulted in the best user experience.