Problem: Stress is a reaction of the body to external challenges, whether physical or psychological. In sports, there are stress factors that affect the athlete's performance, especially American football, because it is a team sport that involves short, high-intensity exercise cycles followed by a short recovery period. The lack of stress regulation mechanisms can be detrimental to the individual and collective performance of athletes. Biofeedback systems have shown promising clinical results in regulating stress for sports competitions. However, there is a lack of scientific evidence to support its efficacy, and technologies such as virtual reality games have not been extensively explored. In this thesis, we report a use case of the development and pilot testing of VANS, a virtual reality game using biofeedback that supports stress management training in athletes. VANS uses an optical heart rate sensor and aims at keeping the heart rate below a given threshold to control features within the game. We evaluated the usability and user experience of VANS through a 1-week deployment study with 10 footballers. Our quantitative results show that VANS outperforms a commercial videogame used for biofeedback training and considerably reduces stress in footballers. Also, VANS could provide stress management training to footballers for future matches and competitions.
Hypothesis: We hypothesize that a VR videogame can provide realistic scenarios and immersion, typically needed during training sessions for footballers.
Keywords: Biofeedback, athletes, stress, virtual reallity
VANS is a VR videogame using biofeedback developed to support stress management training in athletes. The footballer's goal when playing VANS is to win a football tournament by practicing breathing exercises and maintaining your stress. VANS has a narrative to keep the athlete engaged throughout the sessions. In the narrative, a trainer mentions to the athlete that a tournament called "All-champions" will be held in which the athlete has to participate by playing against different teams. Each biofeedback session mimics a game being played in a tournament. Each game has a duration of 15 minutes divided into 3 sets (5 minutes per set).
VANS interface inside the virtual reality system
Interaction measurements: We use the OH1 polar band to measure heart rate. It is a validated device for signal measurement and allows easy and continuous access to data. It is also less intrusive compared to the H10 polar band.
The process begins when VANS, through the polar band OH1 (heart rate, Figure \ref{fig:uml}.1), captures and sends the physiological signals to a processing device (cell phone, PC, tablet). The signals are then received by the mobile device and processed for analysis (Figure \ref{fig:uml}.2). Finally, VANS determines the stimuli and the breathing exercise to be displayed based on the analysis
Evaluation methods: 10 American footballers from a sports center in central Mexico volunteered to participate in the study. The footballers were between 22 and 24 years of age (mean age = 20.8 years; SD = 1.93 years). The participants did not have breathing or heart problems. In addition, none of the participants had attended biofeedback training sessions before. To avoid bias in answering the questionnaires during the evaluation, none of the participants were involved in the design process. All participants consented to the study. All participants played with both the VANS and the STONE videogames. Participants completed two stress management sessions of 20 minutes each, on different days. On the first day, half of the footballers played with VANS and half with STONE. On the second day, footballers who had played with STONE played with VANS and those who had played with VANS played with STONE. This was done to avoid the learning effect. Participants were randomly assigned to each group.
Athlete using STONE (Control group)
Athlete using VANS (Experimental group)
Outcomes and results: Our results suggest that athletes found VANS to be more suitable for the training of stress management in comparison to the STONE videogame. Furthermore, our results suggest that athletes found VANS to be more pleasant, user-friendly, engaging, and immersive for faster and more effective generalization compared to STONE. Although footballers perceived a positive gameplay experience when using both videogames, VANS outperformed STONE in learning of their breathing when using VANS compared to using STONE. In addition, our results suggest that by using the VANS video game, users achieve faster and thus longer relaxation.
Full demo showing how athletes use VANS in practice
We thank other collaborators involved in this project including collaborators and our sponsors: