## 4 Discussion
Thus, future studies are needed in order to deeply evaluate this research issue, which would enable generalization. It should be noted that the self-made preference of the dominant limb is part of an adaptive process that is desirable when performing sport-specific actions [15]. This effect could be particularly relevant while performing karate-specific asymmetrical movements such as a reverse punch (_gyaku zuki_), during which the body mass is displaced from the back lower limb to the front (_zenkutsu-dachi_) stance [12], allowing for an accurate strike. Therefore, the results of the present research can in some way explain the increase in the inter-limb asymmetry after the simulated komite bout, which may result from intramuscular adaptations. However, to the best of the authors' knowledge, currently, there is no data with which to compare the results of our study. Thus, in order to address this issue, further studies are needed to evaluate the impact of a simulated komite bout on asymmetries in the kinematic variables of the lower extremities and komite performance. Moreover, to fully understand the complexity of interactions between the characteristics of sports performance in karate (WKF formula) and its multifaceted effects on the musculoskeletal system, future studies should also assess the mechanical properties of muscle fibers. Considering the impact of limb dominancy on maximal isometric strength performance, our study indicated that the dominant lower limb is not necessarily characterized by higher values of the PVF, as this effect was mainly observed in the U16 athletes during the EXP condition. On the other hand, the non-dominant lower limb was found to be stronger in the U16 group (CTRL, pre-test and post-test), the U18 group (all measurements), and the Seniors (EXP, post-test; CTRL, pre-test). However, in the case of the Senior and U16 athletes, the differences were not large. Our results partly correspond with the findings of [PERSON] et al. (2018), who indicated that karate athletes achieved better results during isokinetic testing in the dominant lower limb. However, as a kumite bout is characterized by unexpected and unstructured technical actions, it seems possible that the higher PVF in the non-dominant lower limb may be related to a greater frequency of kicks (especially with the front lower limb) compared to punches, which requires a higher load on the back lower limb ([PERSON], 2018), the tactical strategy (especially defensive actions) or the athlete's habitual fighting position. Nevertheless, according to the authors' knowledge, this is the first study that assessed the acute effects of a simulated kumite bout on the inter-limb isometric strength asymmetry in the lower limbs; thus, it is difficult to compare our results within the current body of scientific literature. Changes in the percentage of inter-limb asymmetries differed depending on the condition. For instance, due to the kumite bout, the frequency of asymmetries over fifteen percent (>15%) increased in the Seniors and decreased in the athletes from the U16 and U18 age categories (Figure 5). On the other hand, the CTRL condition (post-test) indicated a significant increase in the frequency of asymmetries (>15%) in all age groups; however, the Seniors achieved a lower percentage of the frequency in comparison to the EXP condition. This indicates a favorable impact of the kumite-specific activity on the musculoskeletal system in U16 and U18 athletes; however, this cannot be fully confirmed in Seniors, as in this age group, the kumite bout seems to increase the risk of non-contact injury (asymmetry > 15%), which occurred in 50% of the studied athletes. Our findings are partly in line with the study conducted by [PERSON] et al. (2018), who found that the inter-limb asymmetry in the lower limbs in karatekas differs from less than 10% to up to 15%. On the other hand, [PERSON] et al. (2018) indicated that karate athletes may not present an increased risk of knee injury due to certain training adaptations.