Sixteen youths (average age of 10.7 [SD 0.34] years) participated in this study and completed the 2023 Physical Activity Readiness Questionnaire (PAR-Q) to determine if they were able to perform physical activity without medical supervision [18]. A power analysis using G Power 3.1 was used to estimate the sample size needed for detecting a within-subject difference in raw HR between games and across minutes of gameplay using repeated measures ANOVA. With α set at .05, power at 0.8, a 0.5 correlation among repeated measures, and an estimated effect size of f=0.25, the power analysis determined that 16 participants were needed. Other exclusion criteria included self-reported motion sickness, seizures, and epilepsy. Participants were recruited through email and newspaper advertisements around Indianapolis.

This study was approved by the Indiana University Institutional Review Board (IRB protocol #18787). All participants signed an IRB-approved assent form. Parents or guardians of participants signed an IRB-approved informed consent form. All paper (except informed consent or assent forms) and computer records containing information about participants were identified only by a participant number rather than by participant name. Additionally, all paper records were maintained in a locked filing cabinet in a locked room and were only accessible to the study investigators. Computer data files (without name identifiers) were stored on computer servers with secure passwords or encrypted electronic storage devices. All participants who completed the study were compensated with US $25 in gift cards at the end of the study session.

Participants attended one study session that lasted approximately 2 hours. See Figure 1 for an overview of study session events. The beginning of the session included completing the informed consent and assent, inclusion or exclusion criteria assessment, and demographic questionnaire that included height, weight, ethnicity, age, sex, and VR experience level. Participants rated their experience playing each game using the following options: never, ≤1 time per week, 2‐4 times per week, and ≥5 times per week. Participants were fitted with an HR monitor wrapped around the chest with the sensor at the xiphoid process and accelerometers placed on the dominant wrist and wrapped around the waist with the sensor placed on the right side at hip level. Participants were asked to sit quietly for 10 minutes to collect resting HR. Participants were fitted with the VR headset and shown how to use the VR controllers, with the remainder of the session devoted to playing both Gorilla Tag and Beat Saber. The order of the games was counterbalanced among participants. First, one game was played for a 5‐10-minute familiarization period. Most participants received 5 minutes, but a few participants who did not understand the movement system received more time at the discretion of the researchers. Participants rested for 5 minutes and then completed a 15-minute data collection period of VR gameplay. Participants played at a self-selected intensity. Next, participants rested for 10 minutes and then completed the same procedure for the second game. RPEs were collected at the end of each 15-minute gameplay, and an enjoyment questionnaire was completed following each game. Physical activity intensity during gameplay was measured with an HR watch, chest strap, and 2 accelerometers during each session.

Sixteen participants (13 male) enrolled in this study. The average age of participants was 10.7 (SD 0.34) years. Fourteen participants identified as Caucasian and 2 identified as African American. Eight participants had prior experience playing Gorilla Tag, while 11 participants had experience playing Beat Saber. The heart rate was not collected properly for 1 participant (male); thus, this participant was not included in the HR data analysis.

The repeated measures ANOVA revealed a significant main effect of the game (P=.004, η_p²=0.46) and time (P<.001, η_p²=0.64). The main effects were superseded by a significant game × time interaction, P=.009 (η_p²=0.34). The simple effects tests of the game within each timepoint were significant (P’s<.01), except at baseline (P=.952). HR was significantly greater during Gorilla Tag at each timepoint during gameplay compared to Beat Saber. The simple effects tests of time were significant within Gorilla Tag (P=.003) and Beat Saber (P=.012). For Gorilla Tag, HR during all timepoints of gameplay (1‐4 min, 5‐9 min, and 10‐14 min) was significantly greater than baseline. For Beat Saber, HR at 5‐9 minutes and 10‐14 minutes was greater than baseline. In addition, HR at 5‐9 minutes was greater than HR at 1‐4 minutes. See Figure 4 for HR across time for each game.

See Table 1 for the means and SDs for the %HRR variables, RPE measures, and PACES scores for each game. The dependent t tests revealed significantly higher average %HRR (P=.004) and maximum %HRR (P=.011) for Gorilla Tag compared to Beat Saber. For Gorilla Tag, the average %HRR was equivalent to light physical activity, while the maximum %HRR was equivalent to moderate-intensity physical activity. Based on the %HRR values, Beat Saber reached a maximum of light-intensity physical activity. The analysis conducted on the percentage of time in MVPA (based on %HRR) was significant (P=.036), with participants obtaining a greater amount of MVPA during Gorilla Tag compared to Beat Saber.

The dependent t tests did not show significant differences between games for maximum RPE (P=.352) and average RPE (P=.362). No significant differences existed between games for PACES score, P=.931. The frequency of item responses for each item of the PACES is presented in Tables 2 and 3.

With our society becoming increasingly sedentary, innovative strategies are needed to increase physical activity. Given the increasing popularity of video games among children and adolescents, VR active games could be used to increase physical activity in this age group. However, since this technology is new, a lack of research exists on whether these newer games engage participants in MVPA. To our knowledge, our study is the first to examine physical activity, RPE, and enjoyment in early adolescent youths playing the widely popular games Gorilla Tag and Beat Saber. Our study found that both VR games produced light- to moderate-intensity physical activity while being rated as highly enjoyable.

The first hypothesis stated Gorilla Tag and Beat Saber would produce light to moderate physical activity. The HR data partially supported this hypothesis, with both games increasing participants’ HR significantly from baseline to during gameplay. Gorilla Tag elicited significantly higher %HRR and higher %MVPA than Beat Saber. Based on %HRR data, physical activity during Gorilla Tag was on-average light and a maximum of moderate, with over 25% of playtime spent in MVPA (based on HR data). Beat Saber elicited very light physical activity to light physical activity, with only an average of 5% of playtime spent in MVPA. These results are similar to prior studies in adults, which indicate that adults play Beat Saber at a very light to light intensity [6,13]. For example, one study examining actual versus perceived exertion found that while playing Beat Saber actual and perceived exertion were in the light to very light range [13]. Similar to our study, Godfrey et al [17] found that youths aged 8‐12 years had significantly higher HR while playing Beat Saber compared to rest. In addition, based on a 4-minute period of gameplay, participants had %HRR and metabolic equivalents of task values consistent with light intensity. In the Godfrey study, participants were connected to tubing to measure VO2, which may have restricted movement. However, our study’s results suggest that even when youths are less restricted in movement, Beat Saber is still only played at a light intensity.

Our accelerometer data also provided insight into the type and intensity of movement during both games. The accelerometer data showed similar trends to HR with significantly more moderate to vigorous movement of the arm and whole body (ie, waist accelerometer) during Gorilla Tag compared to Beat Saber. For Gorilla Tag, participants spent significant time in upper-body movement (~97%) and just under half the time in whole-body movement. During Beat Saber, participants spent most of their time (≥89%) in MVPA for the arm but little time in whole-body movement (~13%). This is likely because Beat Saber is an upper-body-based game requiring very little lower-body activity to be successful. The Beat Saber accelerometer data were similar to Evans et al [6], who found adults spent a high percentage of time in arm MVPA but little time in whole-body MVPA while playing Beat Saber. Likely, the significant upper-body movement required to play Beat Saber does not, by itself, induce physiological changes consistent with higher cardiovascular physical activity intensity levels (ie, intensity based on HR). Indeed, several studies found that whole-body movement versus arm movement measured via accelerometers is more important for energy expenditure during active gaming [29,32]. For example, Naugle et al [29] revealed that whole-body MVPA (waist accelerometer), but not arm MVPA (wrist accelerometer), predicted energy expenditure during active gaming as measured by a portable metabolic measurement system during gameplay.

The perceived intensity of physical activity was measured during gameplay via RPE with the children’s OMNI scale. The RPE data indicated that participants rated their exertion toward the middle of the scale as “getting more tired” to “tired” for both Gorilla Tag and Beat Saber. In contrast to the HR data, no differences were found in perceived intensity between games. Several explanations could explain these contrasting results. First, even though the OMNI RPE scale has been validated in children [22], it is possible participants did not fully understand the scale. Participants could have been rated on the difficulty of the game to be successful rather than on the physical exertion of playing the game. Additionally, prior studies show that VR games cause inaccurate perceptions of exertion during physical activity via distraction from bodily sensations [12,13,33]. Further, because RPE ratings were taken at the end of gameplay, it is possible that the ratings could have been influenced by fatigue, depending on the fitness of the participants. Finally, several other potential factors that were unexplored in this study may have contributed to this discrepancy between the HR and RPE data, including age, gender, and experience. Future research should explore the potential factors underlying the discrepancy between HR and RPE data during VR games.

The final hypothesis was that playing both Gorilla Tag and Beat Saber would elicit high levels of enjoyment. The PACES data supported this hypothesis, with both games having an average score above 4 (5 representing the maximum enjoyment) with no difference between games. In a prior study of over 600 children using the PACES, participants rated enjoyment related to physical activity just under a score of 4 [31]. Perhaps active VR games could enhance physical activity enjoyment in youth. Enjoying physical activity is extremely important for physical activity participation in youth. Indeed, DiLorenzo and colleagues [34] revealed physical activity enjoyment was the only consistent predictor of physical activity levels among 5th- and 6th-grade children. Future research should examine whether youth enjoy the active VR games more than traditional exercises completed at a similar intensity.

A few limitations of this study should be noted. First, the game modes, maps, and settings were all constrained to attempt to provide some standardization across the games for each participant. Using different game settings could have potentially provided different results, such as greater physical exertion or enjoyment levels. In addition, given that Gorilla Tag is an online multiplayer game, enjoyment may also significantly increase in Gorilla Tag if participants were able to play online with their friends. Second, the sample was small and comprised primarily of male and Caucasian children. Thus, whether these results generalize to females and children of other races is unknown. Third, prior active gaming studies have found prior game experience and skill level can contribute to physical activity levels during gameplay [35,36]. Participants in this study had a mix of VR experiences. Fourth, this study did not include measurement for the frequency or habitual activity level of the participants. Fifth, there was only one session of gameplay, and how youth play the games may change over time with repeated play. Prior studies suggest motivation to play active video games may decline over time after the novelty of the games wears off [37]. However, this has not been tested with active VR games that allow for a range of experiences. Lastly, Beat Saber provides a proficiency score following each song indicating the number of blocks successfully cut as a percentage. These data were not collected and could have been used to explore correlations with enjoyment or activity level.

To broaden the applicability of the results, future studies evaluating Gorilla Tag or Beat Saber should compare gameplay at different game settings (Beat Saber: normal vs hard difficulty levels; Gorilla Tag: playing with a friend vs strangers) among participants. Future research should also explore how intensity and movement patterns change with more experience in Gorilla Tag and Beat Saber, as well as compare the gameplay of individuals who are active compared to nonactive. Furthermore, longitudinal studies should assess physical activity and enjoyment during gameplay across multiple sessions of gameplay.

In conclusion, Beat Saber produced light-intensity physical activity, and Gorilla Tag produced light- to moderate-intensity physical activity in early adolescent youth, with both games rated as highly enjoyable. Beat Saber primarily involved upper-extremity movement, while Gorilla Tag elicited upper-extremity and whole-body movement. Future research should evaluate more VR active games as a potential mode of physical activity in youth, particularly games that incorporate whole-body movement. Active VR games could potentially be a part of a larger program for exercise-adverse youth in many settings. Enjoyment of physical activity through VR games may foster greater intrinsic motivation in youth to play these active games and hence enhance physical activity participation. However, more research is needed to confirm these hypotheses.