The effect of eight weeks of virtual reality-based physical training on kinematic indicators of gait, muscle strength, and balance in women with Multiple Sclerosis

Multiple sclerosis is an autoimmune disease and one of the most common myelin-destroying diseases in the central nervous system. Approximately 2.5 million people are globally affected by this disease, and the number of infected people is increasing daily. Although no known method is available for treating MS, several strategies have been proposed to improve the function of the locomotor system and prevent disease progression. Temporarily, it has been well established that traditional exercise programs, including aerobic and resistance training programs, play an essential role in increasing muscle strength, improving balance, mental health, social relationships, and self-reliance in patients with MS. On the other hand, in recent years, researchers have considered virtual technologies and have achieved beneficial results in other patients. However, few studies have been done until a decade ago to examine the effect of virtual reality-based physical exercise on the physical health of patients with MS. Therefore, the current aimed to investigate the effect of a virtual reality-based physical training course on kinematic parameters of gait, muscle strength, and balance in patients with MS.

The present study is applied in terms of purpose and quasi-experimental in terms of method. The statistical population consisted of all women with MS referred to the MS Association, Tehran, Iran, in 1400. The sampling method was purposeful and available, and eventually, 20 participants were selected based on the inclusion criteria with an age range of 20 to 40 years and divided into two groups of ten equal by simple random sampling. Then, the researcher measured the subjects of the two groups of pre-test measurements, including muscle strength, kinematic gait indices, dynamic, and static balance. Forty-eight hours after the pre-test measurements, the subjects in the training group performed sports activities according to the designed protocol for eight weeks, 3-weekly sessions, and each session for 45 minutes. Forty-eight hours after the last training session, post-test measurements were performed under the same pre-test conditions. A motion analysis device made by the American company Motion Analysis and the software of the German Cortex device with six cameras were used to measure the kinematic indices of patients' gait. A standard isokinetic dynamometer was used to assess the strength of the lower body muscles. This study measured isokinetic power in two ways, eccentric and concentric, at two angular speeds of 60 and 180 degrees per second in the superior leg. Static and dynamic equilibrium was measured using a Biodex balance meter (Model 590-32). An independent t-test was used to analyze and compare the data between groups. The significance level was considered for statistical comparisons (P<0.05).

The present study's results revealed that the mean maximum strength of knee extensor muscles at angles of 60 degrees (P=0.014) and 180 degrees (P=0.007) was significantly higher than in the control group. In the training group, the strength of the knee flexor muscles at angles of 60 degrees (P=0.003) and 180 degrees (P=0.034) was significantly higher than in the control group. Furthermore, the training group’s kinematic indices of stride length (P=0.006) and stride speed (P=0.001) were significantly higher than in the control group. In the training group, Kinematic indices of step time (P=0.031) and dual support (P=0.013) at the end of the study period were significantly lower than in the control group. Static balance in three general levels (P=0.001), anterior-posterior (P=0.032), and middle-lateral (P=0.001) in the training group were significantly better than in the control group. Correspondingly, dynamic balance at three levels (P=0.002), anterior-posterior (P=0.001), and middle-lateral (P=0.004) at the end of the study in the training group were significantly better than in the control group.
Table 3. Mean and standard deviation of muscle strength of training and control groups in the pre-test and post-test



P-Value
Training Group
Control Group
Variables


Post-test
Pre-test
Post-test
Pre-test


0.006
8.2± 64.2
6.3± 66.4
3.6± 74.1
7.2± 65.2
Step length (cm)


0.031
0.4± 0.55
0.3± 0.58
0.5± 0.52
0.8± 0.56
Step time (seconds)


0.013
8.3± 36.1
5.6± 37.6
7.2± 32.8
4.3± 36.7
Dual support (percentage)


0.001
9.7± 46.4
8.2± 47.3
7.3± 51.1
4.6± 48.6
Walking rhythm (steps per minute)

The present study concluded that eight weeks of virtual reality physical training significantly increased strength, balance, and kinematic gait indices in patients with MS. One of the main reasons for the positive effect of virtual reality-based physical exercises is the new and exciting nature of this type of exercise. Auditory and visual stimuli in virtual exercises are attractive to the patient. In addition, when the patient wins or loses, they can receive appropriate feedback information from the device, which encourages the patient to repeat the movement. In these exercises, the patient, knowing that the activity environment is a virtual environment, tries to adapt to and interact constructively with it and overcome the limitations of the real world. Thus, virtual reality has various positive features that can increase motivation, performance, satisfaction, and engagement and encourage the person to continue as much exercise as possible, including the following: 1- Frequent and intense exercises in a simple, colorful, attractive and motivating environment in the game text. 2- Introducing new games in each treatment session and increasing the game’s complexity following the development of the patient's ability level because new motor skills can lead to better learning and functional plasticity of the nervous system. 4- The activity causes sensory-motor and visual and rapid auditory feedback during or after the game.
Ethical Considerations
Compliance with ethical guidelines
The present study included ethical principles such as obtaining informed consent, the confidentiality of participants keeping their information confidential, and the coding of participants' names. The study also provided sufficient information on how to conduct the research. In addition, participants were free to leave the study at any phase of this study.
Authors contributions
Article writing: Somayeh Taheri; Analysis of statistical findings and scientific and literary editing of the article: Shahab Parvinpour and Marzieh Balali.
Funding
The amount of ten million Rials from the financial resources of Islamic Azad University, Central Tehran Branch, was considered for this research.
Acknowledgments
We would like to thank all the participants in this study for their cooperation and sincere cooperation, as well as all the managers and staff of MS centers, Tehran, Iran who cooperated with us in collecting the findings of the present study. It is worth mentioning that this article is taken from the PhD dissertation of the first author with the code 14350402972008 at Islamic Azad University, Central Tehran Branch.
Conflicts of interests
The authors of the present article state that there is no conflict of interest in writing this research.