Assessment of enjoyment and intensity of physical 2 activity in immersive virtual reality on the 3 omni-directional Omni treadmill and Icaros flight 4 simulator in the context of recommendations for 5 health 6

The aim of the study is to assess enjoyment and intensity of physical exercise while 15 practicing physical activity (PA) in immersive virtual reality (IVR) using innovative training 16 devices (omni-directional Omni treadmill and Icaros Pro flight simulator). The study also contains 17 the results of subjective research on the usefulness of such a form of PA in the opinion of users. In 18 total, 61 adults (10 women and 50 men) took part in the study. To assess the enjoyment level (EL) 19 Interest/Enjoyment subscale of Intrinsic Motivation Inventory (IMI) was used. Exercise intensity 20 was assessed during 10-minute sessions of active video games (AVGs) in IVR based on heart rate 21 (HR). The average enjoyment level during physical exercise in IVR on the tested training devices 22 was relatively high (Omni 5.74 points, Icaros 5.60 points). In the opinion of the majority of 23 participants, AVGs on IVR training devices constitute a sufficiently useful form of movement to 24 meet the needs of PA practiced in free time, and they can even replace some of the classic forms of 25 movement. Intensity of PA during games on training devices was at the level recommended for 26 health benefits for 92% (Omni) and 84% (Icaros Pro) of its duration. Based on the conducted 27 research, it can be assumed that AVGs in IVR using a multi-directional treadmill and a flight 28 simulator can be an effective tool for increasing participation in health-oriented PA. 29


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The lack of movement (hypokinesia) is the main cause of the incidence of chronic 35 non-communicable diseases, causing 71% of all deaths per year, including as much as 40% of 36 premature deaths [1]. Therefore, health promotion activities are currently focused on searching for 37 tools popularizing modern physical activity (PA), attractive for people, tailored to their interests, 38 fitness abilities and leisure time budgets.

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The development of modern technology is considered to be one of the reasons for the 40 decreasing PA level in everyday life [2]. Due to the fact that they constitute an inseparable element of 41 the development of civilization in recent years, technological innovations have been used to So far, published scientific reports confirm a high level of enjoyment during various AVGs and 48 exergames [3][4][5]. It should be noted that according to the results of research on components of 49 behavioral engagement in performing PA, enjoyment is its significant predictor, regardless of age of 50 the study participants [6][7][8][9] and their health status [10][11][12]. It was also observed that due to the high 51 rating of the attractiveness of games of this type, players are able to perform PA longer in an 52 interactive form, compared to classic PA, which may translate into better health effects [13].

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In addition, the results of monitoring the parameters of physical exercise during many active 54 video games showed that their values are at the level recommended for health by international 55 organizations [14][15][16][17][18][19] and contribute to the health benefits of both healthy people [13,20,21] and 56 patients [22][23][24].

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Another aspect of using technological progress in improving public health is the transfer of 58 AVG to virtual reality (VR) -a computer-created space to which users move using special goggles.

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These goggles enable the players to be cut off from the real world, making them part of the game and 60 multiplying the emotions they experiences during it [25]. This most advanced technique, enabling 61 the highest degree of realism in which a person is cut off from the visual and auditory stimuli of the 62 real environment, and instead receives the image and sound, and even tactile sensations of the 63 simulated world, is often referred to as immersive virtual reality (IVR) [26,27].

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Analysis of the few research studies concerning PA in VR that have been created over the last 65 few years, indicates the possibilities of using this modern technology in physiotherapy. A study 66 conducted by Baños et al. [28] shows that walking on a treadmill performed in the virtual world can 67 be better tolerated by obese children than the same physical effort in a traditional form. VR allows 68 for the distraction of the participants from the discomfort that accompanies PA. In addition, moving 69 around in VR turned out to be more attractive to obese children than a typical treadmill walk.

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According to the authors, the use of VR technology in training programs may be a factor increasing 71 motivation to exercise, which may be important in the prevention of overweight and in the fight 72 against obesity. It seems that the reduced feeling of discomfort during exercise in a virtual 73 environment and the attractiveness of this type of PA can be also used in therapeutic treatment in 74 patients with other dysfunctions, which are accompanied by various ailments associated with 75 physical effort. Reports by Baños et al. [28] seem to confirm the results of a study conducted by 76 Matsangidou et al. [29], which showed that PA in VR can affect the perception of pain observed 77 during isometric exercise, which results in lower subjective perception of exercise severity and, 78 consequently, the possibility of continuing the activity and a higher assessment of its attractiveness 79 in comparison with PA performed in a classical manner.

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Inclusion criteria included: age (>18), signing a statement about good general health and the lack of 105 medical contraindicators to participate in the study (physical limitations affecting exercise e.g.:

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pregnancy, injury, etc., no history of seizures or epilepsy, taking any medications affecting heart 107 rate). In the studies using the Omni treadmill (Virtuix) (Fig. 1)

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More than half of the participants (34 people) declared that they had previously experienced 116 immersive VR using computer games using VR headset, while no one had previously had the 117 opportunity to practice PA in virtual reality on the tested training devices.

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The research procedure consisted of a 10-minute session of an active video game on at least one 121 of the two studied simulators. Before proceeding to the above research activities, the researchers

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were even of the opinion that PA on the Omni platform can replace typical, real forms of physical 282 activity practiced in free time, such as walking and running. However, most participants testing 283 Icaros (60%) were convinced that simulator training is able to replace typical exercises in a support 284 position (Table 1).  publications aimed at assessing the above-mentioned parameters during PA using innovative VR 296 training devices. In this context, our study seems original.

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The assessment of enjoyment during PA is of great importance in shaping the motivational 298 instruction to take action, which from the perspective of public health is currently, among others, 299 regular participation in physical activity [9,46] Icaros, which was a difficult task for the participants.

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The high assessment of the usability of PA in VR on training devices is also emphasized by the 313 participants' declarations, which showed that having such training devices they would be happy to

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In the studies presented in this paper, the PA parameters were also evaluated in terms of their