## 2 Materials and Methods
### Study Protocol
#### 2.4.1 Description  
Before the actual sessions, specific equipment and configurations were required:  
* A virtual reality headset (Meta Quest 2) including a pre-installed AdapRehabVR application (current software system presented) with hand tracking and (optionally) controllers;
* Guardian scanning (the space where the activity is carried out in the virtual environment)--it can be stationary (a circle with a diameter of approx. 1 m around the chair on which the patient is seated) or room-scale (a play area of minimum 2 m \(\times\) 2 m, allowing the user more freedom of movement);
* Pulse oximeter O2 ring, monitoring the user's heart rate and oxygen level on the ViHealth app installed on the therapist's mobile phone;
* (optional) Laptop/mobile phone for real-time tracking of exercises performed by the patient using the Meta Horizon application and casting capabilities.  
During the actual experiment, the following steps were carried out, in the place established by mutual agreement with the medical staff (clinic, hospital, the patient's home). All the steps are performed by the patient in a sitting position and using a stationary boundary requiring a space of a circle with 1 m diameter, in order to minimize the risks of motion sickness and avoid restrictions related to limited space:  
1. Listening to the indications and details about the project and how the experiment will be conducted;2. Completing and signing the informed consent and GDPR agreement; the informed consent describes the project in detail and the implications and rights of the user, as well as possible risks and side effects, while the GDPR agreement mentions how the users' data will be used;
3. Completing the demographic questionnaire (demographic questions, state of health questions, and self-evaluation of technological experience);
4. Completing the initial self-efficacy and affective distress questionnaires;
5. Accommodation with the virtual reality headset and the environment, including explanations of the games;
6. Carrying out the tasks corresponding to the test protocol in virtual reality, as follows: \(\bullet\) Physical recovery exercise \"Whack-a-mole\"--1 min;
7. Deep breathing exercise--1 min;
8. Relaxation (relaxing music)--30 s;
9. Physical recovery exercise \"Boxing\" or \"Fruit picking\"--1 min;
10. Progressive muscle relaxation exercise--1 min.
11. Completing the general feedback questionnaire;
12. Completing the final self-efficacy and affective distress questionnaires.  
As an observation, steps 1-5 were performed only during the first session, and step 6 was repeated daily, while steps 7-8 were performed only on the last day of the clinical trial. The suitable exercise to perform with each patient between boxing and collecting fruits was chosen based on the strict indications of the physiotherapists supervising the clinical tests, according to the affections of each patient, and was kept until the end of the clinical trial. Boxing was preferred for shoulder affections, while collecting fruits was suitable for improving fine motor capacities of the wrist or various neuropathies. Constant improvements were brought to the exercises based on the users' feedback, including the addition of more difficulty options, real-time feedback, and audio cues.  
This section presents the entire study protocol, as it was discussed with medical professionals and agreed upon by the ethics committee of the medical institution involved in the clinical study. All procedures and tests comply with the ethical standards in the Helsinki Declaration of 1975, as revised in 2008(5).