# Effects of the Weight and Balance of Head-Mounted Displays on Physical Load
## 4 Results
### Questionnaire Results  
#### 4.2.1 Physical Load  
The questionnaire results providing subjective feedback regarding the physical load are shown for the \"front\" (Figures 4 and 5), \"both\" (Figures 6 and 7), and \"rear\" (Figures 8 and 9) groups.  
On average, the participants gave HMD fixation to the head about a score of 4 (i.e., slightly agree), indicating that most participants did not feel discomfort. We conducted a three-factor mixed ANOVA for each scale on age, gender, and weight condition and identified significant weight condition-related trends for \"front\" group (F(2,198) = 5.402, \(p\) = 0.005). Age only emerged as a factor in the analysis of the \"Both\" group (F(1,168) = 6.491, \(p\) = 0.012). The participants rated the sharpness of the graphics approximately 4 on average (slightly agree), indicating that most participants did not suffer significant focus-related issues during game play. We conducted the same ANOVA, which identified the significance  
Figure 3: Game completion time for female participants. (*: \(p\) < 0.05, **: \(p\) < 0.01).  
Figure 2: Game completion time for male participants. (*: \(p\) < 0.05, **: \(p\) < 0.01).  
of the weight condition factor for the \"front\" group (F(2,198) = 5.851, \(p\) = 0.005) and the age factor for the \"both\" group (F(1,168) = 9.202, \(p\) = 0.029).  
Visual fatigue was reported by some participants. The ANOVA revealed gender-related differences for the \"both\" and \"rear\" groups (front: F(1,198) = 5.402, \(p\) = 0.005, rear: F(1,174) = 5.402, \(p\) = 0.005).  
Increasing the weight also induced fatigue in the participants. In this case, the ANOVA identified significant weight condition-related trends in the \"front\" and \"both\" groups (front: F(2,198) = 27.960, \(p\) = 0.000, both: F(2,168) = 6.849, \(p\) = 0.001), with these groups reporting considerable increases in fatigue as the weight added to the HMD was increased. Gender was highlighted as a factor exclusively in the \"front\" group (F(1,198) = 12.834, \(p\) = 0.000). In addition, age-related trends were observed in the \"both\" and \"rear\" groups (both: F(1,168) = 3.935, \(p\) = 0.049, rear: F(1,174) = 8.266, \(p\) = 0.005). Participants also reported feeling balance-related fatigue for some of the heavier weight conditions. The ANOVA results indicated the weight condition as a notable factor in the \"front\" and \"both\" groups (front: F(2,198) = 11.221, \(p\) = 0.000, both: F(2,168) = 5.402, \(p\) = 0.005). For these two groups, as the weight increased, feelings of fatigue increased substantially. Moreover, gender and age were revealed to be significant factors in the \"front\" group (gender: F(1,198) = 9.066, \(p\) = 0.003, age: F(1,198) = 4.757, \(p\) = 0.030). Age was also identified as an important factor in the \"rear\" group (F(1,174) = 5.622, \(p\) = 0.019). For the \"both\" group, the fatigue gradients corresponding to weight and balance were less than those for the \"front\" group. In contrast, the results for the \"rear\" group showed no significant differences between the various condition. In particular, the plots based on the responses by the young female group exhibited the possibility to be opposite gradients to those for the \"front\" group.  
Figure 4: Questionnaire results for male participants in the \"front\" group. The results of Q1 to Q5 are shown from left to right. (*: \(p\) < 0.05, **: \(p\) < 0.01).  
Figure 5: Questionnaire results for female participants in the “front” group. The results of Q1 to Q5 are shown from left to right. (*: \(p\) < 0.05, **: \(p\) < 0.01).  
Figure 8: Questionnaire results for male participants in the “rear” group. The results of Q1 to Q5 are shown from left to right. (*: \(p<0.05\)).  
Figure 6: Questionnaire results for male participants in the “both” group. The results of Q1 to Q5 are shown from left to right. (*: \(p<0.05\),**: \(p<0.01\)).  
Figure 7: Questionnaire results for female participants in the “both” group. The results of Q1 to Q5 are shown from left to right. (*: \(p<0.01\)).