## 4 Discussion
In our study, differences were also determined when comparing interactions between cap-only use and combined helmet and goggles use, when observing both groups, both when the skier (visual stimuli) was approaching from the left and from the right side (\(p<0.01\)). The results of the aforementioned study indicate that well-fitting ski helmet use did not increase mean reaction time to peripheral stimuli when compared to ski-cap-only use. In contrast, the usage of ski goggles increased mean reaction time to peripheral stimuli. Some of the reasons for decreased peripheral vision when using goggles might be their protective design and their thick frames that are positioned very close to the eyes. At the same time, they increase the distance between the frames and the eye, which may cause greater peripheral vision interference. Most of the time, the central vision is oriented towards the perception of relevant objects and of fine details in a still image, while peripheral vision is designed to notice changes in the visual field itself, especially in the peripheral parts that are outside of the primary focus. When there is an obstruction in front of the eyes, it is even more challenging to identify and recruit information received from the peripheral vision and react adequately and timely. The additional time it takes to respond to a target when wearing a helmet translates to a slower response to a forthcoming threat, which can directly reduce an athlete's ability to avoid or brace for an impact, thereby increasing potential for injury [18]. When further discussing the role of the goggles in visual perception, [PERSON] et al. [19] aimed to determine the effects of goggles on reaction time when detecting targets. Their negative effect was most evident in the peripheral rings. Their results showed that goggles impaired visual target detection, i.e., goggles may negatively affect the detection of peripheral visual stimuli. The authors came to a very similar conclusion to ours regarding the impairment caused by goggles. When observing the influence of headgear on visual performance in other sports, [PERSON] and [PERSON] [12] examined the role of visual perception in the performance of hockey players. Based on their results, it can be concluded that a faster reaction time could directly be related to a higher percentage of success in scored goals. The effects of protective headgear on peripheral visual field, response time and visual target localization were also measured in American football. The mentioned components of vision were the subject matter of a study conducted by [PERSON] et al. [20]. They tested three conditions of protective headgear usage: baseline (with no headgear), wearing only a helmet, and wearing a helmet combined with an eye shield. Participants underwent a peripheral vision reaction-time-testing protocol for each predefined condition. Visual stimuli detection was better during baseline than in the helmet-only condition (\(p<0.001\)) and with a helmet with an eye shield (\(p<0.001\)). Average, peak, minimum, and median peripheral reaction times were significantly better and faster during baseline than when wearing protective headgear (\(p<0.001\)). There were no significant differences between two conditions of wearing protective headgear (\(p>0.05\)). For example, in our study, there were differences determined between the tested combinations of wearing protective headgear, i.e., ski cap and sunglasses, differed significantly between helmet and goggles combinations (\(p<0.01\), for both groups in both tested sides). Additionally, differences were found when comparing helmet users and non-users in combinations of helmet and goggles (interaction 3 vs. 6, \(p<0.01\)), but not when wearing a ski cap and sunglasses (interaction 2 vs. 5, \(p>0.05\)). The findings of the related study suggest that protective football headgear negatively influences reaction time to visual stimuli located in the periphery. These results enable practical applications in order to enhance player safety and reduce injury risk.