# The Acute Influence of Whole-Body Cryotherapy on Electromyographic Signals and Jumping Tasks
## 4 Discussion
Apart from the changes in elasticity, the eccentric force parameter, associated with storing energy when landing, also increased. According to [PERSON] et al., both changes weigh in favor of increasing the risk of injury to bone structure. The changes in elasticity after WBC correspond to the observations made by [PERSON] et al. and [PERSON] et al. [14; 15]. They analyzed the stability of ankle and knee joints after local cryotherapy. Decreased postural stability is a primary risk factor; a cold pack for 20-15 min negatively influenced dynamic postural-stability performance for lower-limb musculoskeletal injuries. The corresponding effect on tissues of WBC at \(-135\)\({}^{\circ}\)C and at a much higher cooling agent temperature with a longer application period (local cryotherapy) may be associated with the spontaneous contraction of superficial vessels. This is in favor of the results obtained by [PERSON] et al., who revealed that the use of cold compresses (with a higher cooling agent temperature) does not have an impact on knee joint position sense and force production sense [26]. A short-lasting, low thermal stimulus cannot affect mechanical response. Our study shows the significant effect of WBC exposure on CMJ in tissue elasticity, where the results changed in both groups before and after the 3 min exposition of WBC. In a study conducted by [PERSON] and [PERSON], the authors state that, in a single vertical jump, leg stiffness appears relatively constant when measuring the parameters without exposure to a low temperature [22; 27]. In our study, parameters differed after exposition on WBC, and less stiffness was observed before stimulation than after 3 min. In youth sports, neuromuscular injury prevention programs (IPPs) can reduce the rate of injury by about 40%. Multimodal IPP includes balance, strength, power, and jumping exercises. Our study shows that the direct use of WBC may have a negative effect on strength and power. [PERSON] et al. argue that neuromuscular performance can be regarded as the ability of the neuromuscular system to functionally control and drive movements by an appropriate use and coordination of muscular strength and endurance, muscle recruitment pattern, proprioceptive feedback, and reflex activity [28; 29; 30]. Another phase of searching for changes to the musculoskeletal system includes the SEMG test of the rectus femoris muscle. The SEMG amplitude did not increase significantly. In our study, resting bioelectric activity of the thigh muscle did not differ after the WBC exposition in 1 and 3 min (\(p<0.46\), \(p<0.73\)). By contrast, using MVC normalization, significant differences were noted after both 1 and 3 min. This study has some limitations. Firstly, it was only conducted in one center, and the changes revealed in our study had a high standard deviation. Therefore, no significant effect after WBC may lead to the conclusion that WBC did not have an impact on the recruitment of motor units in our testing group. Secondly, the parameters analyzed in the study refer to young people with no comorbid conditions; therefore, the results should be treated with great caution. Given that WBC is very popular, future research should remain focused on the causes of the reduced elasticity in musculoskeletal system tissue.