"Balance Training Through Immersive Virtual Reality to Optimize the Balance of the Elderly and its Influence on the Fear of Falls"

Human aging is characterized by gradual loss of functional
capacity, resulting in physical and cognitive changes, due to the
progressive reduction in the ability to adapt to environmental
stressors, which leads to the loss of the ability to maintain
homeostatic balance...


Introduction
Human aging is characterized by gradual loss of functional capacity, resulting in physical and cognitive changes, due to the progressive reduction in the ability to adapt to environmental stressors, which leads to the loss of the ability to maintain homeostatic balance [1]. Among the changes inherent to this process, those related to postural control stand out, where a compromise in the abilities of the central nervous system (SNC) is identified, in the processing of vestibular, visual and proprioceptive signals, which are responsible for maintaining the body balance.
This variable, in turn, plays an important role in orienting the individual in space, allowing the maintenance of posture in different daily situations [2]. The alteration of the functional balance is one of the main factors that limits the life of the elderly, being the fall the most aggravating consequence of this impairment. Approximately 40% of Brazilian elderly people fall at least once a year, while 11% fall on a recurring basis, which may determine consequences not only physical, but also psychic. After a fall event, the elderly begins to live with the feeling of fear of suffering a new episode of fall, and then start to restrict their daily activities [3,4]. Thus, the feeling of insecurity and constant fear, ends up conditioning the elderly to a reduction in mobility, in view of the imminent risk of falling. After his first fall, self-confidence in carrying out his activities goes downhill. Over time this becomes a vicious cycle, and soon there will be a progressive impairment of functional capacity, which in turn leads to a greater propensity for episodes of new falls [5].
With the advent of technology, several resources have been implemented in different areas of health, with special emphasis on immersive virtual reality (RVI), which, within the scope of Gerontology, has been gaining important notoriety, especially in the prevention and rehabilitation of elderly people at risk of falls [6]. Playfulness makes virtual reality therapy more attractive to the patient, improving not only physical health, but also self-esteem.
It is, therefore, a new opportunity for intervention that increases adherence to treatment [7]. The RVI has the ability to stimulate multiple sensory modalities, creating an interface where the individual immerses itself in a virtual environment, similar to real events, allowing the use of games that offer different motor and cognitive demands, enabling feedback on performance and results, try to try, stimulating the search for better performance, therefore being an excellent motivational component [8]. Thus, because it is a tool that, although new, is already being used in treatments, especially with the elderly, and, understanding its potential positive effect in the perspective of rehabilitation of body balance and consequent reduction of fear of falls, seeking to generate scientific evidence, this study aimed to evaluate the effect of a balance training in immersive virtual reality on the functional balance and its influence on the fear of falling in the elderly.

Materials and Methods
This study was an experimental research, carried out at Physiotherapy School Clinic of University center CESMAC. The Subsequently, we proceeded with the assessment of balance, carried out through the Dynamic Gait Index (DGI) test, which is a test that assesses the functional dynamic balance. and each task will receive a decreasing score from 3 to 0, where 3 represents a normal result for that particular task, 2 has a mild impairment, 1 has a moderate impairment, and 0 characterizes a severe impairment to perform that task. Overall score below 19 results in increased risk of falling [9]. Then, the Timed Up and Go (TUG) test was performed, which assesses mobility, speed, agility and dynamic balance, while the individual gets up from the chair and travels a distance of 3 meters. The test begins with the elderly person sitting in a chair with an upright spine, hands on thighs and feet flat on the floor.
The evaluator gives the command, the participant gets up from the chair, goes to the marked point and returns until he / she sits down again, returning to the starting position. Doing this as quickly as possible, without running. Results below 10 seconds indicate that the elderly person has independence for basic transfers, results equal to or greater than 30 seconds indicate that the elderly person is dependent for carrying out their transfers [10].
To assess the fear of falling, the Falls Effectiveness Scale -International (FES-I), consisting of 16 items, was used, where each item represents a daily activity performed by the individual, with 4 possible answers (not at all concerned; one little worried; very worried; extremely worried). The individual will weigh each item according to his level of concern and the situation of the fall occurrence. Total scores between 16 and 19 indicate little concern about falls, between 20 and 27 indicate moderate concern about falls, and between 28 and 64 indicate great concern about falls [11].
After the initial evaluation, each elderly person's service days were scheduled, always interspersed, and the intervention stage was  Table 3.   ¹P-value for the "t" test for paired samples.

Discussion
The analysis of data from the study presented here, allowed and instructed to take care of their health more frequently when compared to men [12]. Contrary to the reality of the majority of the elderly in the Northeast, the participants in this study had a high level of education. This fact can be explained by the recruitment site for the elderly, an active aging course. According to Esper et al. [13] there is a greater tendency for elderly people with higher education to attend these types of activities. As a result, this public is increasingly looking for continuing education, as it allows them to increase their capacities for understanding and actively coping with the repercussions currently occurring [13].
As for the place of fall, the result brings a number very close when comparing falling on the street with falling at home, however, there was a greater number of falls on the street. When epidemiology portrays the place where falls occur, it points to the home as the main place of accidents, together with the surroundings of the individual's home. In this case, the surroundings of the house are characterized as the external environment, that is, the street [14]. The biggest cause of falls was slipping and tripping. The data showed a higher rate of falls on the street and urban mobility has a great influence on this aspect. The discontinuation of the sidewalks, the unevenness, the presence of holes and inadequate lighting, characterize factors of high risk for the elderly. It is noteworthy that these people have a progression of loss of functional capacities, presence of less muscle mass, a greater number of associated morbidities, leading to a worse functional state to face these existing extrinsic factors [14,15]. The balance optimization found in this study is corroborated by other studies that also investigated the influence of VR on the components of postural control [16,17].
According to Phu et al. [17], in a study carried out to ascertain the effectiveness of VR training in reducing falls in the elderly, which also used the DGI test as a parameter for assessing balance, obtained positive results in the assessment that outcome. The authors report an increase in the support base of the participants, resulting in greater stability and greater safety in relation to falling, concluding that training with VR is a good ally for obtaining balance gain for patients, being an auxiliary resource to the treatment [17].
Duque et al. [18] in a study also carried out to evaluate the effect of balance training with VR in the elderly, showed a significant improvement in the parameters established for balance in the intervention group, after 6 weeks of training, also obtaining a reduction in the incidence of falls during this period. After nine months of training, the patients underwent a new evaluation, which resulted in a positive result for the maintenance and improvement of balance, however, there was no significant reduction in the episodes of falling in this reassessment [18]. Training using virtual reality involves tasks that stimulate cognition, as well as motor skills, generating an improvement in the user's balance, contributing to greater independence in activities of daily living, compared to training based only on motor exercises DE et al. [19].
In order to maintain balance, there is a need for integrity of the sensorimotor system, which includes muscle strength, proprioception and anticipatory and adaptive mechanisms, which are facilitated by immediate visual feedback due to interaction with the virtual reality system [20]. However, for the population participating in this study, the increase in functional balance and mobility was not enough to decrease the fear of falling, which goes against the results obtained by other studies of a similar character, such as the one by Camacho and Gomes (2017) [15]. It can be suggested that, because the training took place in a virtual indoor environment, and the episodes of falls pointed out by the research participants were the home environment and around it, it did not generate significant security to have a decrease in this fear of falling [15,17]. In addition, the major cause of falls recorded in the study was tripping and slipping, these are situations arising from walking. As a result, the individual tends to increase or decrease the fear of falling, when he is placed in a situation that he has already fallen. Therefore, the games used in therapy did not require the act of walking, and it may be something that did not lead the elderly to remember the fear of falling, and with that in the end, they did not improve in this regard [4].
Something that can also be taken into consideration is the period of therapy. Due to the fact that the research was carried out with only 16 sessions, it may have been a short period, so that the participants had the perception that the balance was improving their activities of daily living. And the failure to obtain this feeling that the balance has improved, together with the proposed environment in virtual reality is not the environment similar to the fall, may have raised the feeling of fear of falling [5,21]. Perhaps the best training for the elderly, which obtains greater effectiveness is not indoor, but a training that brings them to their common environment. And offering a greater number of sessions, thus increasing the training time, so that you can more effectively obtain the perception and raise the feeling of security from the fear of falling. As studies on the theme of virtual reality are still in small quantities and new, there is a need for more research with this type of approach, to add to the range of resources generating a more effective and attractive therapy for the user. Fear of falling is characterized as one of the most disabling sequelae in the elderly, being presented in 88.5% of cases of post-fall, it brings with it a decrease in mobility and an increase in muscle disuse. That is, the inactivity caused by fear exacerbates the functional and balance loss, this fear can progress and become debilitating, directly impacting the daily activities of the elderly [22,23].
The fear that a new episode of falling may happen, may become a starting point for psychological manifestations in the elderly, such as anxiety symptoms, low self-esteem, and present feelings of fragility, insecurity and vulnerability of new episodes. Despite being a multifactorial event and causing physical disorders, it is important to keep an eye on the psychic and behavioral manifestations that the elderly may experience after the fall episode [24][25][26].

Conclusion
This study showed that the immersive virtual reality resource, for the studied population, was effective for optimizing the functional balance, showing no influence on the reduction of fear of falling.