A Review of Virtual Reality Technology in Exercise Training for Older Adults
Louise P P Chan, Ying Cheng, Jamie Y H Ng, Zongji Zheng and Gladys L Y Cheing*
Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hong Kong
Submission: December 17, 2021; Published: February 04, 2022
*Corresponding author: Gladys LY Cheing, Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong
How to cite this article: Chan LPP, Cheng Y, Ng JYH, Zheng Z and Cheing GLY. A Review of Virtual Reality Technology in Exercise Training for Older Adults. J Endocrinol Thyroid Res. 2022; 6(4): 555694. DOI:10.19080/JETR.2022.06.555694
Abstract
Regular physical activity has profoundly positive impact on an individual’s physical and mental wellbeing. Older adults are recommended to engage in moderate-intensity physical activity for at least 30 minutes per day, and for three or more days per week. However, older adults may encounter various barriers which may lead to poor exercise compliance. In recent years, virtual reality (VR) technology has become increasingly popular in healthcare settings, with the aim to improve physical function, cognitive abilities, and mood in older people with chronic diseases. VR-based exercise may improve self-motivation in performing exercise, increase social interaction, and reinforces older adults’ compliance to exercise training. The aim of this review is to evaluate the effectiveness of VR exercise and the potential advantages of incorporating VR-based rehabilitation for the aging population.
Keywords: Exercise; Virtual reality; Older adults; Chronic diseases; Diabetes
Introduction
The global elderly population of over 80-year-old has been estimated an increase from 126.5 million to 446.6 million between 2015 to 2050, more than doubling in this period [1]. Aging is the accumulation of changes over time in physical, psychological, behavioural, and social processes. It is a degeneration process that results in deterioration in body functions, which leads to an increase in risk of developing more than one chronic disease and thus an increased mortality rates [2]. Fall is one of the major health risks in older adults, which negatively impact their quality of life and it imposes a huge economic burden on the health-care system [3]. Maintaining muscle strength, gait stability, and balance control are vital for improving health and reducing risk of falls in older people especially for those with chronic diseases.
Regular exercises can improve general health status in older adults. It can not only improve their immune system and bone density but also have better control over their blood pressure and reduces the risk of developing cardiovascular disease [4-6]. Regular exercise can also build up muscle strength, improves flexibility, postural control, coordination, and balance, thus reduce risk of falling [7]. These benefits are particularly true for people with chronic diseases. For people with diabetes, common complications include peripheral neuropathy in the lower extremities, decline in balance performance and deterioration of the vestibular system, in which these factors increase their risk of falls [3]. Studies have shown that regular physical activity produces modest increments in physical fitness of diabetic subjects and reduces the risk of overall mortality twofold. Hence, physical activity should be an essential part of diabetes management to maintain optimal blood glucose, lipid, and blood pressure levels [8-10]. In terms of exercise protocols, studies have shown that a combination of aerobic and resistance training is more effective for blood glucose management as compared to either type of exercise alone [9].
Regular exercise is of paramount importance to older adults [4], however, many of them encounter difficulties in maintaining regular physical activity, especially when the benefit of exercise is not visible within a short period of time. The common barriers for older adults to adhere to regular exercises include low self-efficacy, lack of motivation, depressed mood, lack of interest, fear of falling, unsafe environment, personal health, physical ability, low expectations, socioeconomic status, inconvenient location, and inability to choose the correct type of exercise [11-14]. There are various strategies that can be adopted to improve exercise compliance in different client groups. Lee et al. suggested several strategies to increase self-efficacy, which includes performance accomplishments, vicarious learning, verbal encouragement,physiological and affective status; in which these can initiate and maintain a positive physical activity behaviour [11].
Nowadays, virtual reality (VR) games are not only confined to the younger generations. There is a developing interest in older adults to attend VR-based rehabilitation program, which could potentially improve their exercise adherence [15]. The use of VR games with stereo televisions may enhance interaction and networking with their peers and increase enjoyment and satisfaction. Such technology could serve to promote healthrelevant activities whilst encouraging social engagement and interaction, which thereby induce a positive attitude and behaviour change [16]. Another study showed that stroke survivors with limitation in activities of daily living can improve upper limb function by videogame-based training using VR technology [17]. However, this study has been excluded due to the enrolment of participants under the age of 65, which did not fulfil the inclusion criteria of the present review.
Exergaming is the term used for video game that can also be used as a form of exercise. It utilizes a VR environment to improve general physical fitness and for therapeutic purposes such as cardiac rehabilitation and neurorehabilitation. This could potentially bridge the gap between gaming and exercising, encouraging participation in physical activity. It also provides a real-time personalized virtual support from coaches and peers to improve behavioural adherence [18]. Depending on the targeted body movements, the resulting energy expenditure of exergames commonly varies from light to moderate [19].
VR holds great potential in enhancing treatment fidelity and offers an exciting aid in accelerating and sustaining behavioural change. As compared to VR, the immersive experience in augmented reality (AR) might further engage participants in the treatment process. In addition, the VR/AR environment provides an enjoyable experience for participants through personalized treatment program, which also encourages engagement in the intervention and offers unparalleled opportunity to enhance treatment enactment [18, 20]. On the other hand, the combination of training with VR not only induces benefits that conventional physical training has, but also provides immediate feedback that can facilitate motor learning and maximize therapeutic benefits. This can encourage patients to overcome their own limits in the pursuit of better performance [21]. Therefore, VR rehabilitation programmes can be conducted in line with current best practice for balance training in falls prevention [19,22].
The benefit of exercise is well-documented and has extensive evidence to support the effectiveness of VR exercises in improving physical, psychological, and social aspects of older adults [23]. Our mini review aims to summarize studies that evaluated the effectiveness of VR exercise in specific aspects including balance, mobility, cognitive function, mood and self-motivation, quality of life and social life in older adults.
Methods
Randomized controlled trials that implemented virtual reality interventions in older adults’ rehabilitation were retrieved from seven electronic databases including healthcare related and psychological databases: CINAHL, EMBASE, MEDLINE, PubMed, Web of Science, Scopus and PsychINFO databases. Timeframe was set from 2000 to 2020, and the following search strategies were used: “Exercise” AND “Virtual reality” AND “Senior Adults” OR “Elderly” OR “Older Adults”. An advanced search was conducted by adding key terms such as “Chronic diseases” OR “Diabetes”. Studies that targeted older adult population (individuals over the age of 65 years old), published between 2000 and 2020 and in English with full text available are included. Studies that did not fulfill inclusion criterion and any duplicates from search were excluded.
Results
Study selection
A total of 14 studies (4 RCTs, 1 cross-sectional study, 1 pilot study and 8 quantitative studies) were selected for the purpose of this review. Three studies investigated the effects of exercise in older adults [4,24,25]; four studies examined the effects of virtual reality in the elderly cohort [7,20,26,27]; two studies explored the benefits of VR in obese/overweight individuals [16,18]; three studies illustrated the use of VR in other patient cohorts including Parkinson’s, stroke, and haemodialysis patients [21,22,28]. Two studies evaluated the effectiveness of virtual reality in diabetic patients [9,10] (Figure 1).
Outcome measures have been categorized into five domains, including reduced falls risk and improved balance, mobility performance, enhanced cognitive function and social life. The study design, sample size calculation, outcome measures, and results are presented in Table 1.
VR Exercise Reduces Falls Risk and Improves Balance Performance
Aging and diabetes complications are common risk factors of falls. Falls can be caused by reduced muscle strength or muscle atrophy, which results in declined functions in the lower extremities. Jin et al. [29] proposed a multi-barycentric area model (MBAM) to examine human balance capacity based on visual stimulation under VR environment. This model describes body balance condition by computing center of gravity using a triangle area surrounded by upper, middle, and lower parts of the body. The analysis of projection coordinates from the triangle can provide objective measures of balance dysfunction and therefore a more accurate data on an individual’s balance ability. This proposed research has provided valuable results for future investigations in adopting such classification in patients with balance dysfunction and potentially applicable to an extensive cohort of patients such as stroke and multiple sclerosis individuals. VR-based exercise can be easily translated into appealing, easy applicable, and potentially cost-effective videogame-based training regimes or intergenerational balance training targeting falls prevention in older adults [4,10,19,22].
In recent years, VR technology plays an important role in exercise training of balance performance. Findings showed that playing VR games can improve Berg Balance Scale (BBS) scores and extend the stability limits of institutionalized and frail older adults with history of falls [6,12,20,22]. Video games are considered as a new nonmedical intervention for elderly, allowing them to maintain good health conditions by engaging in regular physical and cognitive exercises [20,26]. The use of VR games is not only limited to the older adult population, but it is also evident that fully immersive VR training systems can also bring positive impact to cardiovascular and muscular parameters in young healthy population [30]. Many studies have examined the potential benefits for VR amongst older population and has concluded the implementation of VR in balance training to be effective for falls prevention [19,22,29].
VR-based Exercise Improves Mobility Performance
Sensory inputs are essential for initiating any movements, in which VR exercise provide an opportunity to integrate motor and sensory system to interact with video-game based exercise. The reaching component can be used to assess an individual’s ability to move through the entire range of their body. Upperlimb sensorimotor function can be assessed using visually guided reaching, as it requires input from both sensory and motor system. This can improve the full spectrum of physical functioning, from finest finger motions to gross movements involving the whole body [31].
Mocanu et al [26] proposed a smart home platform to enhance mobility in older adults, using two core components, namely Physical Activity Training (PAT) and Vital Signs Monitoring (VSM). This platform is designed to tackle the major barrier to physical activity in older adults that is adherence to exercise program. The purpose of PAT is to monitor individual’s movement during physical activity. It computes the joint’s relative positioning error, which will then provide immediate visual feedback and guidance for correction. VSM offers an online platform for medical professionals to monitor individual’s condition, medication, and treatment plan. These two components together create a holistic approach for patient care. This study has concluded positive feedback, where users have reported system to be very personalized and have commented that these features have increased their motivation and enhanced their mobility [26]. Similarly, in another study that explored the effectiveness of Online-Gym concluded consistent results, where specifically found improved hand-eye coordination and delayed onset of memory decline in older adults.
Hsieh et al. [7] conducted a study to explore the cognitive and physical effects of VR-based Tai Chi program on older adults with cognitive impairment. Exercise regimes consist of tasks that progressively gets more complex and covers essential activity of daily living. Outcome measures used in this study assessed both cognitive and physical components; including 6-min walk test, 30-s sit-to-stand test, functional reach, 5m / sec gait speed, abstract thinking, and judgment. The VR-based Tai Chi group showed significant improvement in these assessed components, demonstrating a positive effect on their level of fitness.
VR-based Exercise Enhances Cognitive Function
Virtual environment utilized in a video-game setting could educate patients regarding lifestyle management, medication, and nutrition in addition to physical activity. This addresses both cognitive and physical elements of rehabilitation [28]. Crossing road, for example, it provides an opportunity for user to navigate through virtual scenes to mimic everyday life under a controlled environment. Extensive evidence has demonstrated that VRbased exercise enhances cognitive function in older adults. Hsieh et al [7] have also explored the effects of VR-based Tai Chi exercise program on cognitive function of older adults. The VR-based Tai Chi exercise showed a protective effect for cognitive and physical functions in older adults with cognitive impairment.
The more engaging the program, the greater extent of physical and cognitive improvement elicited. The exercise program was delivered twice weekly for 6 months. The duration of each training session varied from 20 to 120 minutes; the frequency varied from 1 to 4 times per week with the overall training program lasted for 4 weeks to 1 year. Participants attended two sessions of 45–60-minute training weekly, in which results have shown significant improvements in balance but no change in lower extremity endurance after three months of VR intervention. It is important to take note that it took at least six months to obtain significant protective effects for other assessed components, such as cognitive function, cardiopulmonary endurance, and mobility function. Therefore, the overall duration of exercise program is recommended to last for at least 6 months to achieve all potential cognitive and physical benefits [7].
VR Exercise Improves Quality of Life, Mood and Self- Motivation
VR-based exercise and social media have been proposed to be promising strategies in increasing users’ motivation and thus their willingness to practice. Research have suggested social media can help overcome boredom and spark the desire to continue physical activity. Family members and friends can share their experience and enjoyment on social media platform, specifically aiming to encourage inclusion of elderly population. Regular physical activity can also improve sleep quality by increasing sleep duration, and thus wake up feeling more energetic and refreshed [20]. Interactive VR games and exercises has opened a new horizon for community dwelling older adults to explore and to foster positive health attitudes.
Research has found that elderly people walk at a slower speed and tire more quickly owing to the loss of strength and mass in lower extremities. Slow walking speed not only correlates with adverse health outcomes, but it also increases the risk of traffic accidents for older people walking in urban areas. Therefore, VR exercises may incorporate appropriate functional training targeting pedestrian safety to reduce risk of traffic accident. Eggenberger et al [24] conducted a cross sectional assessment on walking speed and has observed inadequate fitness level in majority of community-dwelling older patients, putting them at risk at crossroads. This study has suggested training measures aiming to improve elderly population’s cognitive and physical fitness, has positive impact on their walking speed, mobility, and safety [24].
VR has been proven to be an effective strategy in therapeutic programs. Combining exercise training with VR technology enables playful, interactive work and accurate feedback, facilitating patient’s interest and probable adherence to treatment program [21]. Simulating outdoor activities and travelling abroad in VR environment seem to be appealing to older adults who have physical and/or financial limitation. VR cycling, for example, spatial navigation while cycling is now feasible and that older adults have reported similar enjoyment as to younger adults. This technology can continuously motivate older adults to engage in exercises by progressing into different VR scenario, based on their performance and ability [25].
Maynard et al. [21] reported VR training therapy can minimize depressive symptoms. VR training reinforces goal achievement by providing real-time and objective feedback, in which the discrepancies between current performance and targeted goals can be visualized. The application is customized to facilitate accountability and social support from coaches and peers for self-monitoring [18]. Some of them expressed their motivation to maintain regular exercise is to stay fit for their favourite sport or for keeping up with their grandchildren [13]. The goal is to maximize older adults’ level of independence in activities of daily living, which therefore enhance their quality of life.
VR Exercise Promotes Social Participation
Group exercise seems to be a better alternative as compared to doing it alone, since people may feel more supported and motivated when exercising with peers. During VR exercise, older adults can fully immerse into the virtual environment; this can increase their level of motivation and arousal, which enhances their performance as well as their adherence to exercise program. Various studies have demonstrated VR exercise to be effective in reducing the risk of falling, through the improvement of frailty indicators, which can subsequently promote social participation. Therefore, it appears to be interesting in evaluating whether the customization of avatars’ characteristics, perhaps through a reward mechanism, enhances older adults’ participation and engagement in physical activity [20].
Dancing has a dual task character, which potentially stimulates physical and cognitive functions simultaneously. The RCT research proposal hypothesized that dancing has superior effect on improving executive function (e.g., memory, flexible thinking) as compared to physical exercise alone or through exergaming, however there is no evidence available so far [32]. Combining exercise with socialization can make a difficult task easier; it has been shown that older adults who perform physical activity with peers or in groups tend to have better exercise compliance. They enjoy having conversations whilst exercise and that they may perceive time goes by quicker than usual.
Discussion
Aging often leads to various health problems and that can reduce social engagement and have an impact on individual’s mental wellbeing. There are many barriers to physical activity in older adults, which by far, lack of interest is the major factor. It is therefore essential to find innovative methods to motivate older adults to participate in exercise program. VR-based exercise may potentially be a solution to this barrier, as it has been proven to encourage older adults’ self-motivation. This review has evaluated the effectiveness of VR-based exercise in improving balance, mobility, cognitive function, mood and self-motivation, quality of life and social life in older adults. VR exercise training may also contribute to improvement in emotional and social well-being of older adults. Exercise program usually last for 8 weeks or longer, where the dropout rate is usually high owing to low compliance. With the implementation of VR technology, exercise program is more enjoyable and older adults are more likely to adhere to it. VR-based exercise program may also promote physical activities in older adults with chronic diseases, where improvement in physical and cognitive function can allow them to live more independently. This review has highlighted encouraging findings from previous VR-based exercise studies, but a limited number of randomized controlled trials has been conducted on the therapeutic effects of VR-based exercise in people with chronic diseases. More rigorously designed methodology with standardized interventions, larger sample size and multi-centred randomized controlled trials are needed to provide stronger evidence to verify the potential advantages of VR-based exercise [22].
Older adults are recommended to engage in moderateintensity exercise, including muscle-strengthening activities of all major muscle groups for at least 30 minutes, three days per week [14,19,22,33]. Typical exercise training includes progressive weight training programme, weight bearing calisthenics, stair climbing and other strengthening exercises. Stretching exercise is also recommended to be conducted twice a week. Note that the above recommendations on physical activities should be adjusted accordingly depending on the individual’s ability. Particular attention should be paid to elderly with chronic diseases, such as diabetes, hypertension, osteoarthritis, osteoporosis, and cardiovascular diseases. Recently, Lee & Shin [10] found that VR exercise program for older adults with diabetes elicited significant improvement in muscle strength, gait, balance and falls efficacy. Interactive video gaming and VR gaming provided new platforms for the delivery of exercise programs [27]. Colberg et al. [9] reported people with diabetes who performed resistance or aerobic exercise alone have improved their overall glycaemic control. However, for subjects who undergone a combination of aerobic and resistance training, they demonstrated a more effective glycaemic control and a significantly lower HbA1c value as compared to those who performed either type of exercise alone [8,9].
While this mini review has established the physical, mental, and social benefits of VR-based exercise on older adults, some older adults find it difficult to adhere to physical activity, especially when the benefit of exercise is not visible within a short period of time. Exergames make use of VR to create an ecological and controlled environment specifically designed to challenge users. VR is interactive and immersive, which makes physical activity more appealing and more enjoyable for users [21,26]. It provides real-time visual feedback to allow self-correction of motion, which studies have documented valuable therapeutic effects in balance rehabilitation. It has been concluded that exergame has the potential in increasing adherence to treatment and enhancing exercise compliance in older adults [3,20,22].
Furthermore, the use of VR chart to record metrics and track progress of training is helpful by providing quantitative results for older adults, which may encourage them to work harder and prevent drop-outs due to perceived lack of progress. The implementation of novel technology may increase their level of arousal and motivation and motivate them to maintain active lifestyle. In addition, by avoiding the same exercise routine can reduce boredom. User will receive positive visual reinforcement when correct task achieved and this can often intensify the connection between enjoyment and exercise. VR cycling, for instance, may encourage participants to cycle with peers whilst enjoying the stimulated scenarios displayed on the VR system. Various interventions have been explored to improve exercise adherence in older adults; it has been concluded that more feedback and monitoring would promote exercise adherence [34]. VR-based exercise also makes good use of visual and auditory feedback, and these can be useful strategies in encouraging older adults to adhere to physical activity. Future studies can examine whether VR-based exercise can improve exercise compliance for older adults to consolidate this statement.
Conclusion
Virtual reality-based exercise is an interactive and innovative technology to be implemented into exercise program for older adults. Performing exercise with peers through competitive VR games may increase their motivation and satisfaction and therefore increase their exercise compliance. VR exercise can improve balance and mobility that may subsequently reduce the risk of falls. In addition, VR exercises also have a positive impact on cognitive function, quality of life, mood and self-motivation and social life. All the above highlighted positive impact of VR exercises is especially beneficial for older adults with chronic illnesses. Optimized physical health is vital for maintaining independence and quality of life for older adult in this aging population.
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