# Effects of Acute Exposure to Virtually Generated Slip Hazards during Overground Walking
## 3 Results  
For maximum plantar flexion angle on the slipping leg, the repeated-measures ANOVA revealed no statistical significance between gait type (F = 0.473; \(p\) = 0.629; \(\eta_{\text{p}}\)\({}^{2}\) = 0.041) or environmental conditions (F = 0.311; \(p\) = 0.588; \(\eta_{\rm p}\)\({}^{2}\) = 0.011). Additionally, there was no significant interaction between environmental condition and gait type for the maximum plantarflexion angle on the slipping leg (F = 1.136; \(p\) = 0.339; \(\eta_{\rm p}\)\({}^{2}\) = 0.025) (Figure 2).  
For maximum dorsiflexion angle on the slipping leg, there was also no statistically significant difference between gait type (F = 2.328; \(p\) = 0.119; \(\eta_{\rm p}\)\({}^{2}\) = 0.162) nor between environmental conditions (F = 3.299; \(p\) = 0.094; \(\eta_{\rm p}\)\({}^{2}\) = 0.216). There were also no significant interactions observed between environmental condition and gait type for the maximum dorsiflexion angle on the slipping leg (F = 1.758; \(p\) = 0.194; \(\eta_{\rm p}\)\({}^{2}\) = 0.128) (Figure 3).  
For the maximum knee flexion angle of the slipping leg, no statistically significant difference was observed between the environmental conditions (F = 1.077; \(p\) = 0.322, \(\eta_{\rm p}\)\({}^{2}\) = 0.089) and for gait type (F = 2.250; \(p\) = 0.129, \(\eta_{\rm p}\)\({}^{2}\) = 0.170). There was also no  
Figure 3: Maximum dorsiflexion angle (degrees) during normal gait (NG), unexpected slip (US), and expected slip (ES) in REAL and virtual (VR) environments.  
Figure 2: Maximum plantarflexion angle (degrees) during normal gait (NG), unexpected slip (US), and expected slip (ES) in both REAL and virtual VR environments.  
statistically significant interaction between environment and gait type (F = 0.990; \(p\) = 0.388, \(\eta_{\mathrm{p}}\)\({}^{2}\) = 0.083) (Figure 4).  
For SSQ, the paired-samples t-test did not show any significance in scores when comparing before and after exposure to the VR environment (\(p\) = 0.668) (Figure 5).  
For TUG, a significant main effect was observed for TUG-C (F = 4.413; \(p\) = 0.027; \(\eta_{\mathrm{p}}\)\({}^{2}\) = 0.240). Post hoc comparisons revealed significantly lower times following exposure to VR environments compared to baseline (BL) and REAL environment exposure (\(p\) = 0.023). However, no significant differences were revealed for TUG-S or TUG-M. Additionally, significant differences were revealed between environmental conditions (F = 4.304; \(p\) = 0.027; \(\eta_{\mathrm{p}}\)\({}^{2}\) = 0.235). Post hoc comparisons revealed significantly lower times following VR exposure (\(p\) = 0.029). Significance was also observed among comparisons of TUG variations (F = 15.808; \(p\) < 0.001; \(\eta_{\mathrm{p}}\)\({}^{2}\) = 0.530). Post hoc comparisons revealed significantly higher times of completion for the TUG-C when compared to TUG-S (\(p\) < 0.001) and TUG-M (\(p\) < 0.001). The results did not show any significant interactions between environmental conditions and TUG variations (Figure 6).  
Figure 4: Maximum knee joint flexion angle (degrees) during normal gait (NG), unexpected slip (US), and expected slip (ES) in both real and virtual (VR) environments.  
Figure 5: Simulator Sickness Questionnaire (SSQ) scores before (pre) and after (post) exposure to virtual (VR) environments.