Nowadays, stroke is one of the most common leading causes of death in many countries. As the number of stroke patients is increasing, even in younger age groups, there is an increasing need to improve their rehabilitation. In order for this process to start, it is inevitable to integrate the latest recommendations of health and sports science into rehabilitation, in addition to medicine, so that the treatment is as complex as possible. Parkinson's disease is one of the most common neurological diseases, in addition to stroke. The most significant damage can be experienced in motor functions, since one of the main symptoms of the disease is slowed movement, tremor and balance disorders. This postural change can lead to many other musculoskeletal changes, which is why Parkinson's disease is an extremely complex disease that also requires a complex treatment. The third disease examined in our research is multiple sclerosis (MS), which is also one of the most significant nervous system diseases, with nearly 1 million cases registered so far. The most common symptoms of MS patients are weakness, numbness, dizziness, coordination and balance disorders, as well as changes and uncertainty in the gait pattern. One of the essential foundations of rehabilitation after neurological diseases is neurorehabilitation, since the process will only be truly effective if cognitive and motor functions are developed in parallel. In the case of neurological diseases, as we can see above, one of the most significant symptoms is coordination and balance disorders. When the nervous system is affected, trunk control and the patient's posture will always change, depending on the given disease and the individual. One of the fundamental goals of rehabilitation should be to develop stability and postural control, because without these, we will not be able to effectively develop and restore the patients' significant motor functions. This is why it is important that neurological patients are assessed from this perspective as early as possible, so that their treatment plan can be adapted to their disease and themselves as much as possible.

Posturometry: The Tecnobody ProKin stabilometer and posturometer device is currently one of the most effective for objective measurement of static and dynamic balance. The device can be used for both neurological and orthopedic patients. It can effectively measure the trunk control and sense of balance of patients in several ways: on stable or unstable surfaces, and standing on one or two legs. With the help of various programs, the device determines the oscillations of the center of mass (CoP) of the given patient's body, and is able to accurately determine the patient's proprioceptive perception. Furthermore, ProKin can examine the joint movements of the trunk and lower limbs together or even separately. Thanks to these quantified data, we have the opportunity to map the postural instability and balance disorders caused by different patient groups, and thus we will be able to provide a more accurate treatment for our patients. The ProKin device is not only excellent for diagnosis, but also for training, as it contains numerous interactive programs with which we can improve these stability difficulties.

3D motion analysis: With the help of the 3D motion analysis system (Xsens 3D Motion Capture), we can track and record patients' gait patterns in real time. Sensors were used to measure stride length, stride width, and the number of steps taken over a distance of 10 meters.

Exercise program: Each of the selected participants will participate in a training program, which would essentially be a neurorehabilitation training combined with virtual therapy. A session for patients receiving virtual therapy would be structured as follows: 5 minutes of warm-up, 25 minutes of training, 25 minutes of VR, and 5 minutes of cool-down. The main focus of the warm-up is primarily on increasing circulation and introducing them to the workout. While walking or jogging, the patients perform various trunk and limb mobilization and strengthening exercises, first without equipment, and then with equipment (Pilates ball, ball stick, weight ball). The primary focus of the training is primarily on restoring motor functions, which we try to achieve with coordination and balance development exercises, posture correction tasks, and general muscle strengthening. During the exercises, we regularly modify the directions, surfaces, and height levels. These changes can improve both coordination and balance extremely effectively. We also modify the speed of completing the tasks within and between tasks (slow/fast movement execution, length of pause between tasks). The exercises are mostly performed with some kind of device (Dynair cushion, Bosu, Fitball, coordination ladder, barriers, TRX, ball stick, Pilates ball, weight ball). Patients exercise in various body positions, but most exercises are done while walking or standing. One of the most important parts of the training is the development of gait, for which we perform stabilizing exercises and tasks practicing different step patterns with the given modifications and devices. The difficulty of the tasks is adapted to the patient's daily workload and performance capacity each time. The majority of the tasks consist of complex and compound exercises. This neurorehabilitation training significantly improves the adaptability of the nervous system, as the constantly changing sensory stimuli strongly stimulate it, thus developing increasingly better and more precise movements. Another important aspect is the development of cognitive functions in conjunction with movements, since with this level of neuromuscular stimulation (e.g., repetition of complex exercises), these skills can also improve. To implement VR therapy (also known as exergaming), we use Microsoft Xbox 360 and Xbox Kinect devices. These devices are able to sense and record the individual's shape, then place it in a virtual space, and imitate the patient's specific movements. During the therapy, we select three different programs: Kinect Adventure - Reflex Ridge, Kinect Adventure - Space Pop, and Just Dance. The essence of the Reflex Ridge program is that the patient's avatar moves forward on a platform rolling on rails, while constantly having to avoid obstacles from different directions. The system gives more points if the patient manages to avoid as many obstacles as possible without error, and thus the patient's performance can be easily reviewed. The difficulty level can be adjusted according to the frequency of the obstacles appearing. The essence of the Kinect Adventure - Space Pop program is a little more complex, as the patient needs to be able to move better in space. In the game, the participant performs complex spatial coordination tasks by moving their arms up and down and stepping in all directions of the space, trying to collect as many objects as possible, after which they receive points. In this program, reaction time and the ability to quickly change direction will also be the essential task. The third program is Just Dance, where patients have to imitate the movements of the avatars seen on the screen to given music as accurately as possible. The combined use of acoustic and visual stimuli develops motor functions more effectively, so this program proves to be an excellent choice in the rehabilitation of neurological patients. The performance of patients can also be monitored in this program, as after each level the system ranks the precise execution of movements with points, as well as the connection of movements into a continuous one. The cool-down part includes light walking exercises combined with breathing exercises, as well as a stretch designed to relax larger muscle groups.

Data are expressed as mean (±SD). The normal distribution of variables is checked using the Kolmogorov-Smirnov and Shapiro-Wilk tests. Groups are compared at baseline using one-way parametric or Kruskal Wallis analysis of variance. The extent of changes within groups is checked using paired T-test or Wilcoxon test according to the result of the normality test. The results of the groups are interpreted as the difference between the post-intervention and baseline scores. Significant differences between groups are determined using one-way parametric or Kruskal Wallis analysis of variance in the results. Tukey's post hoc test is used to identify values less than p<0.05 between each group. To examine the effect size within groups, Cohen's d is used (very small, 0.01; small, 0.20; medium, 0.50; large, 0.80; very large, 1.20; huge, 2.00) to determine the size of the effects over time. The data are processed using Microsoft Excel and R software.

Exclusion criteria:

• multiple strokes in the medical history
• systolic blood pressure less than 120 or greater than 160 mmHg
• orthostatic hypotension
• carotid artery stenosis
• severe heart disease
• hemophilia
• traumatic brain injury
• seizure disorder
• untreated diabetes
• abnormal electroencephalography
• Mini Mental Test score < 22
• abnormal blood panel
• use of sedatives
• irregular medication
• severe aphasia (Western Aphasia Battery ≤ 25)
• severe vision or hearing impairment
• severe sensory dysfunction
• severe orthopedic problem
• other neurological condition affecting motor functions
• current acute or subacute phase of the disease
• alcoholism, drug use
• smoking after stroke diagnosis
• inability to understand verbal instructions or signals on a television screen
• current participation in an individual or group exercise program in addition to standard physiotherapy
• unable to walk at least 10 meters independently

Inclusion criteria:

• patients with a first-time stroke
• or Parkinson's disease
• or multiple sclerosis
• diagnosed by CT or MRI scan by a neurologist
• exclusively chronic patients
• mobility and postural difficulties as determined by a modified Rankin scale score (≥ 2).