## 4 Discussion  
Warming up, in addition to reducing the risk of injury [22; 25; 26], attempts to increase physical performance in order to prepare players for competitions in the best possible condition [27]. As a result, a suitable warm-up regimen should be of sufficient duration to prevent tiredness. The purpose of this study was to investigate whether three different warm-up lengths affected markers of oxidative stress after exercise and recovery after anaerobic exercise in amateur handball players. This study shows that a 15-min warm-up after 20 min of recovery following anaerobic exercise increases recovery and the return of plasma antioxidants to their baseline levels. Positive changes in all enzymatic antioxidants evaluated accompany the improvements. In our investigation, anaerobic exercise followed by a warm-up was related to an increase in antioxidant plasma concentrations. The three warm-up times resulted in significant increases in SAT, GPx, MDA, TBARSs, and PC in all subjects. Our results followed similar trends to several other studies that have found an increase in plasma MDA and SAT concentrations, as well as blood concentrations of GPx, SOD, and GR, immediately following a 30 s Wingate test in trained judokas [32]. An increase in lipid peroxidation (MDA) occurred, following sprints, strength exercises, and the Wingate test [33; 34; 35] as well as increased plasma concentrations of MDA, SOD, GPX, and GR after the 30 s Wingate test in young adults [36]. The increase in SOD was statistically significant after the two warm-up protocols (5 min and 10 min). On the other hand, a downward trend is observed, during recovery, under the effect of the 15-min warm-up, although the difference is not significant. Nevertheless, our findings are in contrast to those of [PERSON] et al. [9] in whom a Wingate test causes a decrease in SOD activity without modification of GPX activity. This divergence could be explained, in part, by the diversity of the three protocols carried out, the level of physical aptitude which differs between the subjects as well as the individualized response to exercise which could bring exaggerated reactions of oxidative stress during recovery. The same finding, concerning blood GR concentrations, was observed experimentally, under the effect of warming up for 10 min and 15 min. However, after 20 min from the end of the exercise, this parameter's concentrations find their initial values under the effect of the 15-min warm-up with statistically significant differences from those recorded under the effect of 5-min and 10-min warm-ups. The present study showed that a Wingate test, preceded by a three-duration warm-up protocol (5 min, 10 min, or 15 min), resulted in an increase in SAT and MDA concentrations up to a 20-min recovery. In addition, following the 15-min warm-up protocol and after 20 min of recovery, the decrease in SAT concentrations was statistically significant, although the difference is not significant compared to the other two warm-up times. Figure 8: Evolution of TBARSs at recovery after the three warm-up durations. *: significant difference compared to 15-min warm-up at \(p<0.05\). The 5-min and 10-min warm-up protocols showed a significant effect on GPx kinetics during recovery. Indeed, its concentrations continued to increase until 20 min of recovery. In contrast, the 15-min warm-up resulted in a partial drop in GPx concentrations from the cessation of anaerobic exercise until 20 min of recovery, although it was not significant relative to P0. The difference in concentrations at P20 after the 15-min warm-up compared to the other two warm-up protocols (5 min and 10 min), was statistically significant (36.97 \(\pm\) 1.62; 40.87 \(\pm\) 3.75 and 41.55 \(\pm\) 2.55, respectively). A number of explanations could be presented to explain the wide range of responses. The first is connected to the duration of the warm-up, which varies from protocol to protocol.