## 4 Discussion and Conclusions  
The study results point to slight differences between wheelchair fencers from groups A and B with regard to the sequence of muscle activations. In Group B fencers, the movement commenced with the deltoid muscle and then the abdominal muscles. The further sequence was the same as in Group A fencers. It should be emphasized that in both groups of wheelchair fencers, the trunk and abdominal muscles performing postural functions were equally significant [19]. In accordance with Anticipatory Postural Adjustments (APAs) [20], these muscles are activated first or in synergy with the arm extensor muscles. The high dynamics of movement results in balance disturbances. In order to maintain a stable posture, the central nervous system triggers an anticipatory mechanism that activates postural muscles. An analogous effect is observed in able-bodied fencers in the form ofanticipatory activation of muscles (from a few to about 150 ms) of the rear leg, in particular, the gastrocnemius muscle, during the fencing lunge [21]. Thanks to the APA phenomenon the fencer can maintain a stable posture in the wheelchair and quickly move the torso towards the target area following the attacking arm. APAs occur in the trunk during tasks such as rapid limb movement and are impaired in individuals with musculoskeletal and neurological dysfunction. To understand APA impairment, it is important to first determine if APAs can be measured reliably and which characteristics of APAs are task-invariant. Characteristics of trunk muscle APAs quantified during a single task may not be representative of an anticipatory postural control strategy that generalizes across tasks. Therefore, APAs must be assessed during multiple tasks with varying biomechanical demands to adequately investigate mechanisms contributing to movement dysfunction [22]. This results in reduced complex reaction time and movement time in response to the opponent's actions [23,24]. The wavelet analysis also demonstrated the importance of postural muscles in wheelchair fencing training. The specialist training of the trunk and abdominal muscles significantly contributes to improved postural control and balance in wheelchair fencers. Due to the integrity of the motor and sensory neurological system, any neurological deficits can be compensated by the conscious activation of the trunk and abdominal muscles during the preparatory phase, as well as during and after the execution of an offensive technique. Wavelet analysis is a valuable muscle activation assessment tool in the range of lower frequencies, otherwise undetectable by traditional analysis of correlation [25]. The presented method can find application in physiotherapy, as a diagnostic tool, and in the monitoring of training of disabled athletes. The analysis of muscle activation time--as a percentage of three performed attempts in a set--confirmed the earlier assumptions. The fencers from Group A demonstrated shorter activation times in almost all muscles except for the ECR (58.24) compared to Group B fencers. It can be said that postural muscles (abdominal and back) are activated for a shorter time, which confirms the validity of the sequence of activation of postural muscles according to the previously learned technical patterns. This is related to the activation of antagonist muscles, representing a centrally programmed anticipatory mechanism affecting the stabilization of technical actions. As shown by other authors, higher activity levels of antagonist muscles were noted in elite athletes (karatekas) compared to novice practitioners [26,27]. The general assumption of longer activation of most muscles in Group B fencers in intergroup comparisons is, therefore, confirmed. These muscles play a stabilizing role, protecting against injuries. The desired standard co-activation index of the Paralympic wheelchair fencers under study representing two disability categories was within the approximate range of 48 to 51%.