# The Acute Influence of Whole-Body Cryotherapy on Electromyographic Signals and Jumping Tasks
###### Abstract  
Whole-body cryotherapy (WBC) is a popular treatment in prevention as well as post-injury therapy. The parameter used to assess the risk of injury is the ability of the human body to absorb and recover energy (elasticity). Therefore, this study aimed to assess the impact of whole-body cryotherapy (WBC) at 1 and 3 min intervals on the bioelectric activity of lower-limb muscles and countermovement jumps (CMJs) using trained subjects. A total of 24 individuals participated in the study. The mean age of the study group was 27.9 \(\pm\) 7.9 years, mean body weight was 77.9 \(\pm\) 8.8 kg, and mean body height was equal to 181 \(\pm\) 6 cm. The training routine included 2-4 training sessions per week that lasted for at least 2 h at a time (mainly football). Along with the surface electromyography (sEMG) test of the rectus femoris, the BTS G-Sensor inertia measurement device was applied. After three minutes of WBC, a 6% difference in take-off force was noted, with a 7% (\(p\) < 0.04) decrease in elasticity. In the bioelectrical activity of the rectus femoris after MVC normalization, differences (\(p\) < 0.05) were noted 3 min after WBC. In this conducted study, a reduction in flexibility of the lower-limb muscle groups in the CMJ task was noted after 3 min of WBC. whole-body cryotherapy; vertical jump; bioelectrical activity 202212502020202202212502022125022125022122222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222222212122212221222122212212221222122212221222212222122212221222212221222 lower-limb power. In team and individual disciplines, jumping is often used as a form of training [8,9]. The jumping task is associated with the properties of the neuromuscular system, which is responsible for muscle coordination during jumping. The ability of the human body to absorb and recover elastic energy is observed within the tendinomuscular groups. One of the most frequently used tests is the countermovement jump (CMJ). The CMJ is appealing because it is quick to perform and non-fatiguing, and it requires minimal familiarization, yet can yield valuable insight into an athlete's neuromuscular and tendinomuscular groups [10,11]. The use of jumping is also applied in return to physical activity in case of injury. Plyometrics (jumping exercises such as CMJ) is used to rehabilitate the musculoskeletal system. In the available scientific data, there is evidence to suggest that plyometrics is an effective tool for increasing tendon stiffness, improving jumping, lower body strength, and muscle mass [12]. In the rehabilitation of the musculoskeletal system, WBC is often used as a form of pre-exercise for people who have suffered sports injuries. The muscle power generated during this jumping exercise can be very high, despite the low energy cost involved [13]. In one of the studies available in the literature, after WBC with varied exposure times, [PERSON] et al. recorded lower values in jump heights, muscle power, and a maximal velocity of vertical jumps [12]. [PERSON] et al. recorded a reduction in gastrocnemius and vastus lateralis after exposure to low temperatures [13]. [PERSON] et al. and [PERSON] et al. noted changes in the dynamic stabilization of lower-limb joints after cryotherapy and revealed that local cryotherapy might increase the risk of injury [14,15]. Some authors suggested that there was insufficient evidence to support the use of WBC after exercise to prevent and treat muscle soreness in adults [16,17]. As stated by [PERSON] et al., there is a lack of evidence of the best prescription for WBC [18]. Few studies can be found that determine the influence of exposure of WBC to biomechanical parameters of lower limbs in bioelectric activity and CMJ [14]. The current state of research does not provide comprehensive or clear guidelines regarding the application of cold treatment and its direct effect. It has been hypothesized that there are differences between the topical exposure of cryotherapy and WBC and the musculoskeletal system.