## 3 Results
Figure 6: Relationship between body fat and the magnitude of change in temperature of the forearm front and chest. Legend: Fr—forearm; Ch—chest. Figure 7: Relationship between body fat percentage and the magnitude of change in temperature of the forearm front and chest. Legend: Fr—forearm; Ch—chest. Figure 8: Relationship between systolic blood pressure and the magnitude of change in temperature of the anterior and posterior surfaces of the thighs. Figure 10: Relationship between %TBW and the magnitude of change in temperature of the anterior and posterior surfaces of the thighs, chest, and forearm front. Legend: Fr—forearm; Ch—chest. Figure 9: Relationship between diastolic blood pressure and the magnitude of change in temperature of the anterior and posterior surfaces of the thighs. Blood pressure values significantly affected not only the magnitude of temperature decrease in the thigh area but also positively correlated with the values of changes in the area of the anterior surface of the knee joint (r = 0.621; \(p\) = 0.024 for SBP and r = 0.558; \(p\) = 0.047 for DBP). In addition, many relationships were found between the DBP value and the area of the arms (r = 0.673; \(p\) = 0.012 front; r = 0.629; \(p\) = 0.021 back), the anterior part of the forearm (r = 0.615; \(p\) = 0.025), and the upper part of the back (r = 0.602; \(p\) = 0.030). In a further stage of the study, an analysis of changes in the concentration of biochemical blood indicators in football players was carried out, assessing the concentration of lactate (LA) after the match and changes in muscle damage markers, which consisted of measuring the activity of creatine kinase (CK), lactate dehydrogenase (LDH), and aspartate aminotransferase (AST) within 72 h following the match. The dynamics of changes in the concentration of individual markers in the blood serum of the subjects at successive measurement points, i.e., before the match, immediately after the match but before the application of PBC, and then 24, 48, and 72 h after the end of the match, are presented in Figures 11-13. Lactate concentration was significantly higher post- versus pre-match. As a result of the match physical activity, serum lactate values increased on average from 1.78 \(\pm\) 0.36 umol/mL to 5.26 \(\pm\) 1.17 umol/mL (\(p\) < 0.001). The mean pre-exercise values for muscle damage markers were, respectively, 254.98 \(\pm\) 97.16 U/L for CK, 156.24 \(\pm\) 53.63 U/L for LDH, and 22.81 \(\pm\) 3.35 U/L for AST. Immediately after the match, there was a significant increase in CK and AST concentrations, lasting up to 24 h after exercise, when the analyzed concentrations reached their maximum values of 340.11 \(\pm\) 159.08 U/L; \(p\) = 0.0025 for CK and 28.87 \(\pm\) 4.13 U/L; \(p\) = 0.00001 for AST. During the next day (48 h post), a progressive decrease in the concentration of these markers was observed; in the case of CK, these values did not differ significantly from the baseline. On the other hand, for AST the values comparable to the baseline values were recorded only 72 h after the match. Interestingly, in the case of LDH, despite an upward trend in serum concentrations following the match effort and a decrease between 24 and 72 h after the match, no statistically significant differences between the values obtained in subsequent measurements were found. Peak serum LDH concentrations were observed immediately after the match, with the mean value for the group being 190.68 \(\pm\) 109.10 U/L. There was no correlation between the amount of temperature change in the lower extremities and the post-match concentration of the analyzed markers of muscle damage. Figure 11: Creatine kinase concentrations before and after the match and in the course of post-exercise regeneration with the use of partial body cryostimulation. ** significant difference vs. CKpre at \(p\) < 0.01; *** significant difference vs. CKpre at \(p\) < 0.001.