## 4 Discussion
The ease of use was appreciated by all users, scoring an average of 4.26 across all games. This shows once more the appropriateness of the design and the fact that the flexibility of exercises (different levels of difficulty, different backgrounds, skins, etc.) made them suitable for a wide range of people, avoiding both boredom (when games are too easy) and frustration (when games are too difficult). It is interesting to further investigate our research results to analyze if motivation or enjoyment is correlated with game difficulty. Studies show that enjoyment increases if the difficulty matches their gaming experience [32]. Average heart rate levels (76.32 beats/min average across all users), as well as relaxation scores (with an average of 4.57 across all games), show that the levels of stress experienced by patients during the tests were low. This confirms results presented in previous studies, such as the one of [PERSON] et al. [33], which highlighted that VR natural environments can show improvements in distress, depression, and anxiety. Further investigations are necessary to correlate our results from the psychological tests in order to see a clear evolution of the patients' emotions over the VR experience. Considering the results of our study, the recommendations for the practical use of this type of intervention deserve special mention. Home-based technologies are progressively used as an adjunct method in neuromotor rehabilitation plans [34]. The most important benefit of this type of approach is the increased autonomy and perceived control the patient is experiencing. A recent study has outlined the effectiveness of the home-based, self-administered VR intervention plan to reduce low back pain at a three-month distance after the completion of an eight-week treatment program, revealing a meaningful and enduring impact [35]. In our clinical study, the ease of use and the significant level of relaxation the patients have reported are encouraging results in the direction of using these types of technologies at home or in a less-guided rehabilitation setting. Our proposed exercises can be personalized and offer a high level of flexibility (different levels of difficulty or various backgrounds or skins), encouraging the patient's involvement and increasing the familiarity and therefore the comfort and the motivation to pursue a demanding and resource-consuming set of exercises. Whether they are used in the hospital or at home, the correct use of this equipment requires minimum guidance from the medical personnel. In the first several sessions, the patient is encouraged to become familiar with the technical requirements and to let the self-management aspect of the equipment grow on them. Whether used at home with no supervision or in the hospital with minimum guidance, the results for every exercise could be stored for every patient in a personal database, offering an objective measure of the progress in the rehabilitation process. Not only can the progress be monitored, but so can the implementation of the therapist's feedback regarding the number of repetitions or the accuracy of the execution for every exercise. Benefitting from a high level of immersion in a familiar (home-based) and comfortable environment (personalized settings in games) could improve the patient's motivation and engagement and prevent incomplete exercises or even abandonment of the treatment plan. Patientadherence influences the completion of long-term rehabilitation plans and can be increased by the satisfaction gained in a gaming context [36]. There are some limitations of the study that could have influenced the results and discussions presented in the current paper. These research limitations are especially related to the sample size, demographics of the patients, and absence of long-term follow-up on the effectiveness of VR therapy. Therefore, as the clinical study was performed on 25 patients, the results regarding both objective and subjective tools could have been influenced by various demographic biases.