## 4 Discussion  
The aim of this study was to assess the non-alcoholic beer effectiveness as a recovery supplement after 1 h submaximal exercise on several days, observing alterations in plasma antioxidant enzyme activity (GPx, GR, Cat), and in muscle damage levels (LDH enzyme activity), as well as changes in lower limb thermographic values. One of the main findings in this research is that non-alcoholic beer does not show statistically significant changes in the study variables compared to water as a rehydrating beverage. Furthermore, regarding the ES, the NAB group has a medium increase in thermography values (15\({}^{\prime}\)Post-15\({}^{\prime}\)Pre) on days 1 (ThG) and 2 (ThQ) compared to CON; a large increase in LDH activity (both 60\({}^{\prime}\)Post-0\({}^{\prime}\)Post and 60\({}^{\prime}\)Post-Pre) on day 2, and a medium increase (60\({}^{\prime}\)Post-0\({}^{\prime}\)Post) on day 3; a medium decrease in GR (60\({}^{\prime}\)Post-Pre) on days 1 and 3; and a large (60\({}^{\prime}\)Post-0\({}^{\prime}\)Post) and medium (60\({}^{\prime}\)Post-Pre) decrease in GPx on day 3. Even with the rehydration properties of non-alcoholic beer, which are sometimes better than water [23], the findings presented here support the idea that it is not an appropriate recovery beverage after 1 h running for three consecutive days. Acute changes in thermography after exercise are previously studied, but not after running exercises or in consecutive training days. After an isometric and auxotonic training (4 \(\times\) 10 repetitions of 70% maximal isometric squat strength), skin temperature decreased \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{\
\begin{tabular}{c} **Interval** \\ **Comparison** \\ \end{tabular} } & \multirow{2}{*}{**Variable**} & \multirow{2}{*}{**Threshold**} & \multicolumn{3}{c}{**Day 3**} \\ \cline{3-6}  & & & **CON (Mean \(\pm\) SD)** & **NAB (Mean \(\pm\) SD)** & **ES (CI 95\%)** \\ \hline \multirow{4}{*}{60\({}^{\prime}\)Post-0\({}^{\prime}\)Post} & GPx (U) & \(-\)0.20 & 179.47 \(\pm\) 615.45 & \(-\)515.57 \(\pm\) 462.73 & \(-\)1.02 (\(-\)1.87; \(-\)0.17) * \\  & GR (U) & \(-\)0.20 & \(-\)311.18 \(\pm\) 1406.37 & \(-\)1218.37 \(\pm\) 1639.07 & \(-\)0.58 (\(-\)1.68; 0.52) \\  & Cat (U) & \(-\)0.20 & 3.45 \(\pm\) 12.19 & 2.08 \(\pm\) 13.44 & \(-\)0.10 (\(-\)1.15; 0.95) \\  & LDH (U) & 0.20 & \(-\)23.39 \(\pm\) 56.78 & 13.49 \(\pm\) 78.70 & 0.59 (\(-\)0.66; 1.84) \\ \hline \multirow{4}{*}{60\({}^{\prime}\)Post-Pre} & GPx (U) & \(-\)0.20 & 172.91 \(\pm\) 1029.69 & \(-\)515.57 \(\pm\) 462.73 & \(-\)0.60 (\(-\)1.35; 0.14) \\  & GR (U) & \(-\)0.20 & 277.22 \(\pm\) 2061.09 & \(-\)83.61 \(\pm\) 2221.46 & \(-\)0.16 (\(-\)1.19; 0.88) \\ \cline{1-1}  & Cat (U) & \(-\)0.20 & 2.40 \(\pm\) 15.90 & 4.54 \(\pm\) 11.01 & 0.12 (\(-\)0.71; 0.95) \\ \cline{1-1}  & LDH (U) & 0.20 & \(-\)8.69 \(\pm\) 72.42 & \(-\)2.31 \(\pm\) 62.67 & 0.08 (\(-\)0.83; 0.99) \\ \hline \multirow{4}{*}{15\({}^{\prime}\)Post-15\({}^{\prime}\)Pre} & ThQ (\({}^{\circ}\)C) & 0.20 & 0.69 \(\pm\) 0.83 & 0.46 \(\pm\) 0.65 & \(-\)0.26 (\(-\)1.13; 0.61) \\ \cline{1-1}  & ThG (\({}^{\circ}\)C) & 0.20 & 0.23 \(\pm\) 0.70 & 0.46 \(\pm\) 0.70 & 0.30 (\(-\)0.69; 1.28) \\ \hline \hline \end{tabular}
\begin{tabular}{c} CON = control group; NAB = non-alcoholic beer group; SD = standard deviation; ES = effect size; CI = confidence interval; GPx = glutathione peroxidase; GR = glutathione reductase; Cat = catalase; LDH = lactate dehydrogenase; ThQ = thermography in quadriceps; ThG = thermography in gastrocnemius. \\ \hline \end{tabular}
\end{table} 
Table 4: Values variation of plasma enzyme activity and lower limb thermography after non-alcoholic beer supplementation on the third running day. CON, n = 10; NAB, n = 10. * Large ES, ‘0’ value is not included in CI. and recovered baseline values within 15 min of completion [51], similarly to the data obtained in the three days of our study in the control group. Non-alcoholic beer consumption maintained a skin temperature above basal level after 15\({}^{\prime}\) on days 1 and 2.