Comparison of Physical Activity Intensity During Virtual Reality Gaming: Omnidirectional Treadmill Versus Traditional Controllers—A Physiological Assessment

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This research provides evidence-based guidelines for implementing VR-based exercise systems in health promotion programs, demonstrating that omnidirectional treadmill interfaces can achieve vigorous exercise intensities that meet physical activity recommendations.

Abstract

Background: Virtual reality (VR) technology has emerged as a promising tool for promoting physical activity through immersive gaming experiences. This study aimed to compare the physiological responses and perceived exertion during VR gaming using two different locomotion interfaces: omnidirectional treadmill and traditional controllers. Methods: Twenty-one university students (7 women, 14 men; age 23.5 ± 1.4 years) participated in a crossover study comparing physical activity intensity during VR gaming using traditional controllers versus an omnidirectional treadmill (Virtuix Omni). Participants played VRZ Torment for 15 min in each condition, separated by 30 min washout periods. Physiological responses were measured using indirect calorimetry (Cortex METAMAX® 3B), heart rate monitoring (Polar V800), and subjective ratings of perceived exertion (RPE). Exercise intensity was classified according to established guidelines, and user satisfaction was assessed using a 10-point scale. Results: Omnidirectional treadmill locomotion resulted in significantly higher physiological responses and perceived exertion across all measured variables compared to controller-based movement: heart rate (76.7 ± 11.7% vs. 51.7 ± 9.5% HRmax, p < 0.001), metabolic equivalents (7.3 ± 1.7 vs. 2.1 ± 0.3 METs, p < 0.001), and RPE (14.4 ± 2.9 vs. 9.3 ± 1.5, p < 0.001). Treadmill gaming achieved vigorous-intensity exercise, while controller gaming remained at light intensity. User satisfaction was significantly higher with treadmill locomotion (8.5 ± 1.3 vs. 5.0 ± 2.3, p < 0.001). Strong correlations were observed between physiological measures only during high-intensity treadmill exercise. Conclusions: Omnidirectional treadmill VR gaming achieves vigorous-intensity physical activity sufficient to meet health recommendations, while traditional controller gaming provides only light-intensity exercise. These findings support the potential of locomotion-enhanced VR systems for health promotion.

1. Introduction

Promoting regular physical activity remains a global public health priority. The World Health Organization recommends that adults engage in at least 150 min of moderate-intensity or 75 min of vigorous-intensity aerobic activity per week, or an equivalent combination of both, to gain substantial health benefits [1]. Despite this, many individuals fail to meet these guidelines due to barriers such as limited accessibility, low motivation, and poor long-term adherence to conventional exercise programs [2]. These adherence challenges have prompted researchers to explore alternative approaches to physical activity promotion that may better address psychological barriers and enhance exercise enjoyment.

The contemporary technological landscape presents a paradox regarding physical activity and health promotion. Although technological advancements have contributed to the decline in physical activity levels by facilitating sedentary behaviors and digital entertainment, they also offer innovative ways to address this problem [3,4]. The proliferation of digital devices has been associated with an increased amount of sedentary time across all age groups. At the same time, researchers have highlighted a growing “digital health divide” [5]. However, emerging technologies, particularly virtual reality (VR), present unprecedented opportunities to transform how we approach physical activity promotion and health interventions.

The technology landscape for health promotion spans a wide spectrum of sophistication and cost—from expensive, fully immersive VR systems requiring specialized equipment to accessible mobile applications and smartphone-based solutions. This technological diversity offers opportunities for broad population reach across different socioeconomic levels. Recent advances have demonstrated that even simple smartphone technology can provide accurate health monitoring capabilities [6].

Virtual reality (VR) technology has recently emerged as a promising alternative for encouraging physical activity, particularly through immersive gaming experiences—a concept known as “exergaming” [7,8]. VR applications in healthcare and health promotion have expanded rapidly beyond their initial entertainment-focused origins. Multiple studies demonstrate the effectiveness of VR-based interventions across diverse populations and health conditions [9,10,11,12]. In older adults, VR exergaming has shown significant benefits for balance improvement and functional mobility, with motion capture-based systems proving particularly effective when implemented at higher doses exceeding 134 min per week [9]. Similarly, VR interventions have demonstrated efficacy in specialized populations, including children with developmental coordination disorder, where custom VR exergaming systems successfully enhanced cardiopulmonary fitness while maintaining high levels of user enjoyment and motivation [10].

The therapeutic applications of VR extend to clinical rehabilitation settings, where immersive environments have proven beneficial for patients with chronic conditions. A recent systematic review examining VR-based interventions for individuals with chronic low back pain has shown that sensor-based training using exergaming technologies can effectively reduce pain and disability while improving functional outcomes [11]. Furthermore, VR-assisted exergaming has demonstrated superior effectiveness compared to conventional physiotherapy in improving gross motor function and cognitive domains in children with cerebral palsy, suggesting its potential as a complementary therapeutic approach [12].

By integrating engaging gameplay with movement, VR-based exercise systems have demonstrated potential not only to increase user adherence but also to elicit measurable physiological benefits [13,14]. Multiple comparative studies suggest that immersive environments can generate more satisfaction and psychological flow than real-world exercise contexts [15,16,17]. For instance, research comparing cycling in virtual versus real environments has demonstrated significantly higher flow state scores in the VR condition, despite matched workloads between conditions. Recent systematic reviews further confirm VR’s effectiveness in enhancing physical activity motivation and enjoyment across various populations [15], while comparative analyses of outdoor cycling versus virtual and enhanced reality indoor cycling demonstrate significant differences in physiological responses and psychological engagement [17].

The growing body of evidence supports VR’s capacity to address traditional barriers to physical activity participation. Research indicates that immersive VR environments can overcome common obstacles such as lack of motivation, time constraints, and social anxiety, while providing engaging and gamified experiences that enhance adherence to exercise programs [18]. The technology’s ability to create controlled, safe, and adaptable exercise environments makes it particularly valuable for populations with specific health considerations or mobility limitations.

Recent research has demonstrated that VR exergaming can achieve clinically meaningful exercise intensities, particularly when enhanced with strategic modifications. Polechoński et al. [19] showed that the addition of handheld weights (0.5 kg) during VR gaming significantly increased exercise intensity from low to moderate levels, with mean heart rate responses rising from 63.7% to 67.1% of maximum heart rate. This simple modification proved effective and comfortable for users, suggesting practical approaches for optimizing VR-based physical activity interventions without compromising user experience or game enjoyment.

Despite these promising developments, the sedentary lifestyle epidemic continues to pose significant public health challenges. Physical inactivity remains responsible for substantial morbidity and mortality worldwide, with technological factors contributing to prolonged sitting time and reduced energy expenditure [20]. The irony that technology both contributes to and potentially solves this problem highlights the critical importance of understanding how different technological interfaces affect exercise intensity and physiological responses.

A critical factor influencing exercise outcomes in VR is the type of locomotion interface used. Traditional VR systems often rely on handheld controllers with joystick navigation, which primarily engage the upper body [21]. This approach facilitates virtual movement with minimal physical exertion, potentially limiting the health benefits of VR gaming. In contrast, omnidirectional treadmills replicate natural gait mechanics and require full-body movement, offering a higher potential for increased physical exertion [22,23]. These specialized devices allow users to walk, jog, or run in any direction while remaining in a fixed physical location, potentially enabling more naturalistic locomotion within virtual environments.

While virtual walking differs biomechanically from real-world locomotion [24,25,26], treadmill-based VR is generally seen as more physically immersive. Comparative biomechanical analyses have identified several differences between virtual and real-world gait, including altered step length, cadence, and joint kinematics. Despite these differences, treadmill-based VR locomotion still engages the major muscle groups involved in ambulation, thereby potentially enabling meaningful energy expenditure during gameplay.

Standard physiological metrics such as heart rate, oxygen consumption (VO₂), and ratings of perceived exertion (RPE) are commonly used to evaluate exercise intensity. However, the unique sensory and biomechanical aspects of VR environments require nuanced application of these tools [27]. The comprehensive physiological assessment in VR studies necessitates the use of multiple monitoring systems to capture the complex interactions between immersive technology and human physiology. Design elements such as game mode or external loading can further modulate exercise intensity [28,29], underscoring the need for multifactorial assessment.

Although interest in VR-based fitness continues to grow, few studies have directly compared the physiological demands of different VR locomotion methods under identical gameplay conditions. Most existing work isolates either traditional controllers [30,31] or treadmill systems [32,33], limiting the development of evidence-based guidelines for VR-supported health promotion.

This study addresses that gap by comparing exercise intensity between traditional controller-based VR and treadmill-based VR under standardized conditions. The primary purpose of this investigation was to determine whether omnidirectional treadmill-based VR gaming can achieve exercise intensities that meet established health guidelines. The novel element of this study is the direct comparison of physiological responses between two distinct locomotion interfaces within an identical virtual environment. We hypothesize that treadmill-based locomotion will elicit significantly higher physiological responses, achieving vigorous-intensity activity levels capable of fulfilling public health recommendations.

2. Materials and Methods

2.1. Participants

Twenty-one student volunteers (7 women, 14 men) were recruited from the Academy of Physical Education in Katowice. Inclusion criteria comprised the following: (1) age 18–25 years, (2) good general health status (self-reported), (3) physical fitness sufficient to enable 15 min locomotor activities, and (4) no prior experience with the tested VR application or omnidirectional treadmill to avoid skill bias. Exclusion criteria included the following: (1) light sensitivity or epilepsy, (2) history of motion sickness, (3) postural stability disorders, (4) physical limitations affecting locomotion or arm movements, (5) cardiovascular, neurological, or metabolic conditions, and (6) use of medications that influence heart rate. Health screening was conducted via a standardized questionnaire that addressed both inclusion and exclusion criteria.

The study was conducted in the Laboratory of Research on Pro-Health Physical Activity, a specialized facility equipped with physiological monitoring systems and virtual reality technology. This controlled laboratory environment ensured standardized testing conditions across all participants and sessions.

The study was conducted in accordance with the Declaration of Helsinki—Ethical Principles for Medical Research Involving Human Participants (1964) and its latest amendments adopted by the World Medical Association and was approved by the Research Ethics Committee of the Jerzy Kukuczka Academy of Physical Education (protocol 9/2018). All participants provided written informed consent after receiving a detailed explanation of the study procedures, potential risks, and benefits. Participants were informed that they could withdraw from the study at any time without consequences.

2.2. Virtual Reality Setup

VRZ Torment, a first-person shooter survival horror game, served as the standardized VR environment. This game was selected for the following specific reasons: (1) its varied topography (open spaces, enclosed rooms, elevation changes) provided diverse movement demands; (2) frequent directional changes and obstacle navigation required continuous user engagement; (3) variable movement intensity requirements allowed comprehensive physical activity assessment; and (4) it offered compatible gameplay experiences across both controller and treadmill interfaces. The game requires navigation through an abandoned research complex while avoiding threats and engaging hostile entities, generating diverse physical activity patterns representing real-world movement scenarios.

The VR system consisted of an HTC Vive Pro headset (HTC Corporation, Taoyuan, Taiwan) and two controllers. Two locomotion conditions were tested: (1) conventional controller-based movement using joystick manipulation and (2) omnidirectional treadmill locomotion using the Virtuix Omni system (Virtuix Inc., Austin, TX, USA). The controller-based condition utilized the standard HTC Vive controllers, with the left joystick controlling movement direction and speed while the right controller managed interaction and viewing orientation. In this condition, participants remained relatively stationary, using predominantly upper-body movements and thumb manipulation of the joystick to navigate the virtual environment.

The Virtuix Omni omnidirectional treadmill condition enabled physical replication of walking and running movements in virtual space. This system consists of a concave low-friction platform on which users walk or run while wearing specialized low-friction shoes. A stabilizing ring and harness system surrounds the user at waist height, allowing free rotation while preventing falls. Integrated sensors in the platform track foot movements and translate them into proportional virtual locomotion.

Before each session, the VR system was calibrated according to the manufacturer’s specifications. For the HTC Vive system, this included room-scale setup with precise positioning of the base stations and controller calibration. The treadmill harness and specialized low-friction shoes were individually adjusted for each participant to optimize gait replication and ensure safety. The game graphics settings and room-scale boundaries were standardized across all sessions to maintain consistent immersion and performance.

2.3. Experimental Protocol

A crossover design was used with 15 min gaming sessions separated by 30 min washout periods. Participants were assigned to one of two condition orders (controller first or treadmill first) using an alternating sequence as they enrolled in the study. This method ensured a balanced distribution of order among participants and helped reduce the risk of systematic order bias. The 30 min break between sessions was implemented to minimize potential carryover effects on physiological and perceptual responses. The 15 min session length was selected to allow for stable cardiovascular and metabolic responses while minimizing participant fatigue, VR overexposure, or cybersickness. Two-minute 30 s baseline measurements were performed in the standing position before each session to record resting values for heart rate, oxygen uptake, and other physiological parameters. These values were used to calculate relative changes during gameplay.

Before the main trials, each participant completed a brief (5 min) familiarization session on the treadmill to reduce novelty effects and cybersickness risk. This familiarization included instruction on correct foot sliding technique, maintaining posture within the harness system, and controlling direction through body orientation. A similar familiarization was also provided for the controller-based condition, covering the use of the joystick and VR navigation.

To ensure participant safety and data consistency, all sessions were supervised by trained personnel familiar with VR equipment and emergency protocols. Participants were instructed to immediately report any signs of discomfort, dizziness, or motion sickness and were allowed to withdraw from the session at any time without consequence. All sessions were conducted in a climate-controlled laboratory to minimize the impact of environmental factors on physiological responses.

2.4. Physiological Measurements

Exercise intensity was assessed using the following three validated methods:

1

Indirect Calorimetry: A portable ergospirometer (Cortex METAMAX® 3B, Cortex Biophysik GmbH, Leipzig, Germany) measured breath-by-breath oxygen consumption (VO₂) and calculated metabolic equivalents (METs). The system was calibrated before each testing session according to the manufacturer’s guidelines.

2

Heart Rate Monitoring: The Polar V800 system with chest-mounted H7 sensor (Polar Electro Oy, Kempele, Finland) recorded average heart rate (HR_avg) and percentage of maximum heart rate (%HR_max).

3

Subjective Assessment: Rating of Perceived Exertion (RPE) was assessed using the Borg 6–20 scale [34]. This validated scale provides a subjective measure of exercise intensity, with values ranging from 6 (no exertion at all) to 20 (maximal exertion). Participants were familiarized with the scale prior to testing, including standardized explanations of the anchoring points and verbal descriptors.

Exercise intensity classification followed established guidelines [35]: light intensity (50–63% HR_max, 1.1–2.9 METs, 10–11 RPE), moderate intensity (64–76% HR_max, 3–5.9 METs, 12–13 RPE), and vigorous intensity (77–93% HR_max, ≥6 METs, 14–16 RPE). These thresholds align with current physical activity recommendations, allowing for categorization across multiple physiological indicators.

2.5. User Experience Assessment

A participant satisfaction with each gaming modality was evaluated using a 10-point scale (1 = lowest, 10 = highest satisfaction) (Figure 1). This subjective measure was included to complement physiological data with user perceptions, providing a more holistic view of how different locomotion modes affect overall experience. The satisfaction rating was obtained immediately following each gaming session.

2.6. Statistical Analysis

Descriptive statistics included means (M) and standard deviations (SD) for all measured variables. Prior to analysis, data normality was assessed using Shapiro–Wilk tests, which confirmed that the distribution of all key variables did not significantly deviate from normality (all $p>0.05$). Paired-samples t-tests compared physiological responses between conditions, with Cohen’s d calculating effect sizes to determine the magnitude of differences. Effect sizes were interpreted according to conventional thresholds: small (0.2), medium (0.5), and large (0.8).

Spearman correlation coefficients (r_S) assessed relationships between measurement methods (heart rate, METs, and RPE) within each condition. Spearman correlations were selected due to the ordinal nature of the RPE scale and to accommodate any potential non-linear relationships between variables. Statistical significance was set at $\alpha$ = 0.05 for all analyses. All data processing and statistical analyses were performed using Statistica v.13 (TIBCO Software Inc., Palo Alto, CA, USA) and Jamovi v.2.2.3.0 (The jamovi project, Sydney, Australia).

3. Results

3.1. Participant Characteristics

Table 1. Participant characteristics and baseline measurements.

Variable	Women (n = 7)	Men (n = 14)	All (n = 21)
Age (years)	23.1 ± 1.1	23.6 ± 1.5	23.5 ± 1.4
Height (cm)	167.1 ± 7.3	179.6 ± 7.8	175.5 ± 9.6
Body mass (kg)	62.6 ± 12.7	79.1 ± 13.4	73.6 ± 15.2
BMI (kg/m2)	22.3 ± 3.2	24.5 ± 3.9	23.8 ± 3.7
HRrest (bpm)	60.0 ± 8.4	60.9 ± 10.7	60.6 ± 9.8
%HRmax,rest	53.2 ± 5.4	45.3 ± 5.6	48.0 ± 6.6
VO2rest (mL·kg−1·min−1)	5.3 ± 0.7	4.8 ± 0.8	5.0 ± 0.8
METrest	1.5 ± 0.2	1.4 ± 0.2	1.4 ± 0.2

BMI, body mass index; HR, heart rate; VO₂, oxygen consumption; MET, metabolic equivalent.

presents participant characteristics and baseline physiological parameters. The sample comprised physically active university students with normal BMI values and comparable resting physiological measures between sexes.

3.2. Physiological Responses Comparison

Omnidirectional treadmill locomotion produced significantly higher exercise intensity across all physiological measures compared to controller-based movement (

Table 2. Physiological responses during VR gaming with different locomotion interfaces.

Variable	Controller	Treadmill	Mean Difference	t	p	Cohen’s d
HRavg (bpm)	99.1 ± 18.3	147.0 ± 22.4	−48.0	−11.4	<0.001	−2.5
%HRmax	51.7 ± 9.5	76.7 ± 11.7	−25.0	−11.3	<0.001	−2.5
VO2 (mL·kg−1·min−1)	7.2 ± 1.2	25.6 ± 5.9	−18.4	−15.0	<0.001	−3.3
METs	2.1 ± 0.3	7.3 ± 1.7	−5.3	−15.0	<0.001	−3.3
RPE (6–20)	9.3 ± 1.5	14.4 ± 2.9	−5.0	−10.0	<0.001	−2.2
Satisfaction (1–10)	5.0 ± 2.3	8.5 ± 1.3	−3.5	−7.9	<0.001	−1.7

HR, heart rate; VO₂, oxygen consumption; MET, metabolic equivalent; RPE, rating of perceived exertion.

). The magnitude of these differences was both statistically significant and physiologically meaningful, with large effect sizes observed across all variables. Heart rate responses showed a 25% difference in %HR_max (76.7 ± 11.7% vs. 51.7 ± 9.5%, p < 0.001, d = −2.5). This substantial difference translates to approximately 48 beats per minute in absolute terms, representing a clinically significant contrast in cardiovascular demand between conditions.

Metabolic demand, as measured by oxygen consumption and metabolic equivalents, demonstrated the most pronounced differences between conditions. Treadmill locomotion elicited oxygen consumption values more than three times higher than controller-based movement (25.6 ± 5.9 vs. 7.2 ± 1.2 mL·kg⁻¹·min⁻¹, p < 0.001). Similarly, metabolic demand was 5.3 METs higher with treadmill locomotion (7.3 ± 1.7 vs. 2.1 ± 0.3 METs, p < 0.001, d = −3.3).

Subjective exertion ratings demonstrated similar patterns to the objective physiological measures, with RPE values approximately 5 points higher during treadmill locomotion compared to controller-based movement (14.4 ± 2.9 vs. 9.3 ± 1.5 RPE, p < 0.001, d = −2.2). The alignment between subjective perceptions and objective physiological measures supports the internal validity of the assessment approach.

Individual data inspection confirmed that physiological responses were consistent within each condition. Figure 2 illustrates both the group means and individual response distributions, demonstrating the clear separation between conditions across all participants. Treadmill-based locomotion yielded stable, vigorous-intensity results among participants, whereas controller-based movement consistently remained within the light-intensity range. This uniformity supports the reliability of the observed differences between locomotion methods.

3.3. Exercise Intensity Classification

According to established guidelines, omnidirectional treadmill gaming achieved vigorous-intensity exercise across all measurement methods, while controller-based gaming remained at light intensity (Figure 2). The treadmill condition consistently exceeded moderate-intensity thresholds (>64% HR_max, >3 METs, >12 RPE), indicating potential for meeting health recommendations. This classification was consistent across all three measurement approaches (cardiovascular, metabolic, and perceptual), strengthening the validity of the intensity categorization.

3.4. User Experience

Participant satisfaction was significantly higher with omnidirectional treadmill locomotion compared to controller-based movement (8.5 ± 1.3 vs. 5.0 ± 2.3, p < 0.001, d = −1.7), suggesting enhanced user engagement and enjoyment. This difference in satisfaction is particularly noteworthy given the substantially higher physical exertion required by the treadmill interface. The large effect size (d = −1.7) indicates a strong and consistent preference for the more physically demanding locomotion method across participants.

3.5. Correlations Between Measurement Methods

During low-intensity controller gaming, no significant correlations existed between physiological measures: %HR_max vs. METs (r_S = 0.32, p = 0.164), %HR_max vs. RPE (r_S = 0.35, p = 0.124), METs vs. RPE (r_S = 0.25, p = 0.268). The absence of significant relationships between these variables during controller-based activity suggests that at lower exercise intensities, the physiological and perceptual responses may be less tightly coupled.

However, during high-intensity treadmill gaming, substantial and significant correlations emerged between all measurement methods: %HR_max vs. METs (r_S = 0.59, p < 0.01), %HR_max vs. RPE (r_S = 0.58, p < 0.01), and METs vs. RPE (r_S = 0.56, p < 0.01) (Figure 3). These moderate-to-strong correlations during treadmill gaming indicate good concordance between different assessment approaches at higher exercise intensities.

4. Discussion

This study successfully achieved its purpose of comparing exercise intensity between omnidirectional treadmill-based and traditional controller-based VR gaming. Our hypothesis was confirmed, as the treadmill interface elicited significantly higher physiological responses, perceived exertion, and user satisfaction across all measured variables. This study presents the first direct comparison of exercise intensity between traditional controller-based and omnidirectional treadmill VR gaming using a standardized virtual environment and multiple validated physiological assessment methods. The findings demonstrate that the type of locomotion interface has a substantial effect on the physiological load during VR activity; specifically, treadmill-based locomotion induced vigorous-intensity responses, while traditional controller use remained in the light-intensity range.

4.1. Exercise Intensity Differences

The 5.3 MET difference observed between conditions represents a notable physiological gap that translates to substantially different health implications. Participants reached an average of 7.3 METs during treadmill use—well above the vigorous-intensity threshold (≥6 METs)—compared to only 2.1 METs in the controller condition. This difference exceeds the separation between sedentary behavior and moderate-intensity physical activity, highlighting the substantial impact that locomotion interface choice has on the metabolic demands of VR gaming.

To contextualize this difference, the 5.3 MET gap between conditions is comparable to the difference between casual walking (approximately 2.5 METs) and jogging (approximately 7–8 METs). This substantial contrast in energy expenditure has significant implications for the potential health benefits of VR gaming. While controller-based VR represents only a marginal improvement over completely sedentary activities, treadmill-based VR approaches the intensity of traditional aerobic exercise modalities like jogging or cycling.

These results align with prior work highlighting biomechanical differences between real and virtual gait [24,25,26], suggesting that despite altered mechanics, omnidirectional treadmills still elicit high energy expenditure. Previous biomechanical analyses have shown that walking on an omnidirectional treadmill differs from natural overground walking in several parameters, including stride length, step width, and joint kinematics. Despite these biomechanical alterations, our findings indicate that omnidirectional treadmill locomotion nevertheless generates substantial metabolic demand comparable to traditional forms of moderate-to-vigorous physical activity.

The metabolic cost observed in our treadmill condition is notably higher than previous VR gaming studies examining different interaction modalities. Perrin et al. reported elevated heart rate but not energy expenditure during VR bow-shooting games [36], while our results demonstrate both cardiovascular and metabolic responses. This discrepancy likely reflects the full-body locomotor demands of omnidirectional treadmill gaming versus predominantly upper-body VR activities. Recent work examining metabolic cost on the Virtuix Omni supports our findings of substantial energy expenditure during omnidirectional treadmill locomotion [37].

Studies examining different VR activities have shown variable exercise intensities that can be modulated through game design and equipment choices. Research on virtual table tennis has demonstrated that game mode can significantly influence exercise intensity and attractiveness [29], with competitive play eliciting higher heart rates and energy expenditure than casual or practice modes. Similarly, investigations of wheelchair boxing in VR environments have shown that additional loading (such as handheld weights) can effectively increase physiological demands [28].

4.2. Health Promotion Implications

Achieving vigorous-intensity physical activity through treadmill-based VR gaming has clear implications for public health strategies. Current physical activity guidelines recommend at least 75 min of vigorous-intensity aerobic activity per week for substantial health benefits [1]. Our findings suggest that omnidirectional treadmill VR gaming could make a meaningful contribution toward meeting these recommendations, potentially addressing the significant public health challenge of insufficient physical activity.

Beyond exercise intensity, the motivational aspects of virtual reality are equally important for long-term adherence. The higher satisfaction scores observed in the treadmill condition indicate greater user engagement, which is crucial for maintaining regular physical activity over time. This finding aligns with earlier studies demonstrating that immersive VR can lead to greater enjoyment and psychological flow compared to traditional forms of exercise [14,15,16,17]. Flow state—characterized by complete absorption in an activity, temporal distortion, and intrinsic enjoyment—has been linked to increased adherence to physical activity programs and longer exercise session durations.

Moreover, recent research confirms that using innovative VR training devices can combine high enjoyment with exercise intensity levels that meet recommendations for health benefits [38]. Debska et al. [38] demonstrated that immersive VR exercise not only achieved moderate-to-vigorous intensity levels but also maintained high enjoyment ratings across multiple sessions, suggesting sustained engagement potential beyond novelty effects.

Although controller-based VR did not reach recommended intensity thresholds, it may still help inactive individuals take their first steps toward a more active lifestyle. Even low-intensity movement has been shown to offer health advantages for sedentary populations [18], particularly in terms of metabolic health and reduction of sedentary behavior risks.

These findings suggest that VR systems incorporating treadmill locomotion could serve as effective and enjoyable tools for promoting physical activity, particularly in populations resistant to conventional exercise. The combination of immersive experiences with vigorous-intensity movement addresses both physiological and psychological aspects of exercise adherence, potentially overcoming traditional barriers to sustained physical activity participation.

4.3. Measurement Validity and Reliability

During treadmill sessions, strong correlations were observed between heart rate, oxygen consumption, and perceived exertion, supporting the convergent validity of these physiological measures in immersive settings. This aligns with established principles in exercise physiology, which indicate a tight coupling of these variables at moderate-to-high intensity levels [39]. The agreement between objective and subjective measures during high-intensity VR activity suggests that traditional exercise monitoring approaches remain valid in immersive virtual environments.

In contrast, during low-intensity controller gaming, no significant correlations were found between physiological measures. This may reflect both the limited physiological range and the lower sensitivity of these tools in detecting minimal effort. Additionally, the dissociation between psychological engagement and physiological demand during controller-based VR may contribute to this lack of correlation. Participants may have been mentally engaged with the game content while experiencing minimal physiological strain, which could have affected their ability to rate perceived exertion accurately.

Our data confirm that standard physiological metrics can be reliably used in VR contexts, particularly when exercise intensity reaches moderate or higher levels. This finding has practical implications for exercise professionals and researchers working with VR-based interventions, as it suggests that conventional monitoring approaches can be applied without significant modification when the activity elicits substantial physiological responses.

4.4. User Experience and Adherence

The significantly higher satisfaction ratings with treadmill gaming (8.5 ± 1.3 vs. 5.0 ± 2.3) suggest enhanced user engagement, which is crucial for long-term exercise adherence. Similar patterns were reported by Debska et al. [39], who observed that immersive VR devices eliciting moderate-to-vigorous intensity maintained high enjoyment across sessions. The higher satisfaction ratings in the treadmill condition are particularly noteworthy given the substantially higher physical demands of this interface. Typically, as exercise intensity increases, enjoyment tends to decrease, especially in individuals who are not trained. However, our results support findings by Polechoński et al. [14] and Barbour et al. [8], where immersive VR produced higher enjoyment scores compared to equivalent real-world exercise, possibly due to distraction from physical discomfort and increased presence. The fact that participants reported higher satisfaction despite greater exertion suggests that the immersive qualities of the full-body VR experience may override or mitigate the negative affect often associated with vigorous exercise. Other studies, such as Mocco et al. [17], have linked higher presence and flow in VR with improved affective responses, which may explain the strong preference for treadmill locomotion in our sample. This phenomenon warrants further investigation, as it may provide insights into how immersive technologies can be leveraged to enhance adherence to higher-intensity exercise protocols.

It is essential to recognize that the single-item satisfaction measure employed in this study offers a limited assessment of the user experience. Future research should employ validated instruments that capture multiple dimensions of experience, including presence, immersion, flow state, emotional responses, and physical comfort. Additionally, long-term studies are needed to determine whether the higher satisfaction observed in the treadmill condition translates to sustained engagement and exercise adherence over extended periods.

However, practical considerations, including equipment costs, space requirements, and potential cybersickness, must be taken into account for widespread implementation. Current omnidirectional treadmill systems, such as the Virtuix Omni, are expensive (approximately 1500–2500 USD), require substantial dedicated space (approximately 2 m × 2 m minimum), and demand technical expertise for proper setup and maintenance. These factors may limit accessibility for home users and smaller fitness facilities, potentially restricting the scalability of treadmill-based VR interventions.

Furthermore, the specialized footwear and harness systems required for omnidirectional treadmill use may present barriers for specific populations, including older adults, individuals with balance impairments, or those with mobility limitations. Future technological developments may address some of these limitations, potentially making this form of exergaming more accessible to diverse populations.

Future research should examine long-term adherence patterns and optimal training protocols for VR-based exercise programs. Longitudinal studies that track both physiological adaptations and user engagement metrics would provide valuable insights into the sustainability of VR-based exercise interventions and their potential for promoting lasting behavioral change.

4.5. Study Limitations

This study has several important limitations that should be considered when interpreting the results. The sample was limited to young, physically active university students, which naturally restricts the generalizability of the findings to older adults, sedentary individuals, or clinical populations with specific health conditions. The physiological responses and user experiences may differ substantially in these groups due to variations in fitness levels, technology familiarity, and health status. Furthermore, while the sample size was sufficient to detect the large effect sizes observed between conditions, a formal power analysis was not conducted a priori, which represents a methodological limitation. Future research should investigate these interfaces across more diverse populations to develop more inclusive evidence-based guidelines.

Although the crossover design reduced individual variability and learning effects, the participants had no previous experience with omnidirectional treadmill locomotion. This novelty may have temporarily increased engagement and effort, possibly elevating satisfaction and physiological responses. In future research, more extensive familiarization sessions could help minimize such novelty bias, allowing for the assessment of responses after the initial excitement has diminished.

Another limitation relates to the use of a single game environment, VRZ Torment, as the test scenario. While the game offered varied movement demands and immersive challenges, the results may not extend to other gaming genres with different physical requirements. Games with different movement patterns, cognitive demands, or emotional content might elicit different physiological responses and user experiences. A comprehensive understanding of VR exercise would benefit from comparative studies across multiple game types and difficulty levels.

The satisfaction assessment employed a single-item measure rather than a comprehensive, validated instrument for user experience. While this approach provided a general indication of preferences, it did not capture the multidimensional nature of VR experiences, including aspects such as presence, immersion, comfort, and specific components of enjoyment. Future studies should employ standardized, validated instruments to assess these dimensions more thoroughly.

Finally, the short 15 min sessions, although suitable for assessing acute physiological responses, do not reflect longer-term adherence, potential fatigue, or the sustainability of using treadmill-based VR over time. Most health benefits from physical activity accrue through regular, sustained participation rather than isolated sessions. Longitudinal studies are needed to clarify how these systems perform with extended, real-world use, including whether the novelty effect diminishes over time and how this affects adherence and physiological responses.

4.6. Future Research Directions

It would be valuable to investigate the long-term effectiveness and sustainability of VR-based exercise. Longitudinal studies should assess fitness improvements, adherence patterns, and user engagement over time. Research designs incorporating multiple follow-up assessments over 3–6 months would help determine whether initial enthusiasm translates to sustained behavior change and physical adaptations.

Comparative trials across various VR game genres and locomotion designs are warranted to determine how interactive elements influence exercise intensity and user satisfaction. Different game mechanics (exploration vs. combat), narrative contexts (competitive vs. cooperative), and sensory stimuli (visual complexity, audio design) may all modulate both physiological responses and psychological engagement. Understanding these relationships would facilitate the design of more targeted VR exergames for specific health and fitness outcomes.

Additionally, exploring applications in diverse populations—such as older adults, sedentary individuals, and clinical groups—will help assess the therapeutic and rehabilitative potential of VR-based training. Different populations may respond uniquely to various VR interfaces, and optimizing systems for specific user needs could expand the impact of this technology across healthcare contexts.

Studies addressing practical barriers, including equipment cost, space requirements, and usability, are also necessary for broader implementation. Research into more accessible and affordable omnidirectional locomotion solutions could help bridge the gap between laboratory findings and real-world applications. Additionally, investigating hybrid approaches that combine elements of different interfaces might identify optimal combinations of engagement and accessibility.

By advancing research in these areas, VR exercise platforms may evolve into scalable, practical tools for promoting physical activity across a wide range of settings and populations, ultimately contributing to public health efforts to increase physical activity participation.

5. Conclusions

This study successfully achieved its purpose of comparing physical activity intensity between omnidirectional treadmills and traditional controllers during VR gaming. Our results demonstrate that the type of locomotion interface used in virtual reality gaming can significantly impact exercise intensity. Specifically, omnidirectional treadmill locomotion consistently elicited vigorous-intensity physical activity across all physiological measures, meeting thresholds recommended by public health guidelines. In contrast, traditional controller-based VR gaming remained within the range of light intensity. Strong correlations between heart rate, oxygen consumption, and perceived exertion during treadmill use support the validity of standard physiological assessment tools in immersive VR settings. Additionally, the significantly higher satisfaction ratings associated with treadmill gaming suggest that immersive, full-body VR experiences may enhance user engagement and, consequently, exercise adherence. These findings have important implications for the development of VR-based health promotion strategies. Treadmill-enhanced VR systems offer a unique opportunity to combine enjoyable, gamified experiences with physical activity intensities sufficient to confer health benefits. The substantial difference in metabolic cost between interfaces (5.3 METs) highlights the critical importance of selecting the appropriate locomotion method when designing VR-based exercise interventions. In conclusion, our study provides the following compelling evidence: 1. Omnidirectional treadmill-based VR gaming elicits exercise intensities in the vigorous range (7.3 ± 1.7 METs, 76.7 ± 11.7% HRmax), meeting recommended thresholds for health-promoting physical activity. 2. Traditional controller-based VR gaming results in significantly lower exercise intensity (2.1 ± 0.3 METs, 51.7 ± 9.5% HRmax), classified as light activity that is insufficient to meet physical activity guidelines. 3. User satisfaction is significantly higher with the treadmill interface, suggesting greater potential for long-term engagement and adherence. However, successful implementation requires addressing practical considerations such as equipment cost, space, and user accessibility. The current generation of omnidirectional treadmills presents several barriers to widespread adoption, including high purchase costs, substantial space requirements, and limited adaptability to different user characteristics. These factors may restrict their use primarily to specialized facilities or research settings until more affordable and compact alternatives emerge. Further research is needed to assess long-term adherence, optimize game design, and explore applications across broader demographic and clinical populations. In summary, omnidirectional treadmill VR gaming represents a promising and engaging modality for achieving health-relevant physical activity, with potential utility in both recreational and therapeutic contexts. These findings contribute to the growing evidence base supporting technology-enhanced approaches to promoting physical activity and provide practical guidance for designing effective VR exercise interventions.