درخت حوزه‌های تخصصی

Background: Fatigue as one of the physiological factors can affect the physical performance of athletes. This issue is more important in young athletes and can expose them to injury. Aim: The purpose of this research was to investigate the effect of functional fatigue on the performance and landing mechanics of adolescence taekwondo athletes. Materials and Methods: This was a semi-experimental study. Participants were 20 male teenage taekwondo players. Pre-fatigue measurements included side-jump tests, figure-8 hop tests, and single-leg triple jump tests, as well as a lower limb biomechanics assessment using a landing error scoring system. After the functional fatigue protocol was applied, all the pre-fatigue variables were evaluated again. In order to examine the intra-group changes of the research variables in the pre and post-test stages, the paired t-test at a significance level of P≤0.05 was used. Results: The paired-t test results revealed that following fatigue induction, performance in the side-jump and figure-8 hop tests significantly deteriorated (P<0.05). Additionally, performance in the single-leg triple hop test declined (P<0.05). Moreover, landing error significantly increased (P<0.05). Conclusion: The finding of this study indicated that after applying fatigue, the subjects' performance decreased and the biomechanical error of the lower limbs increased. Fatigue can significantly impact adolescent taekwondo athletes' performance and biomechanics. So, taekwondo coaches should implement effective strategies to mitigate fatigue, enhance athletes' conditioning, and optimize their performance in training and competitions.

Background: Cardiovascular disease is a significant contributor to mortality in diabetic patients. Despite the potential benefits of concomitant and complementary training in diabetic patients, there is a paucity of evidence in this area.Aim: The objective of this study was to investigate the effect of aerobic training in conjunction with a hydroalcoholic extract of the fruit of Qaraqat on superoxide dismutase, glutathione peroxidase, total antioxidant capacity, and malondialdehyde in the heart tissue of male rats with type 2 diabetes.Materials and Methods: 24 male rats aged 8 weeks were diabetic with a high-fat diet (60%) and streptozotocin injection. They were randomly divided into four groups: (1) aerobic training (AT), (2) supplementation (Sup), (3) Aerobic training+ supplement (AT+Sup), and (4) diabetes control (Con). The training protocol included running on a treadmill at a speed of 5-24 m/min for 10-60 min, according to the principle of overload. Glucose, insulin, insulin resistance, and MDA, TAC, GPX, and SOD of heart tissue were measured. Statistical tests of two-way variance and post hoc Bonferroni were used using SPSS software at a significance level of P<0.005.Results A significant decrease in glucose levels, insulin resistance, and MDA (P<0.005) was observed in the intervention groups following eight weeks of training and supplement intervention, in comparison to the Con group. Also, the amount of insulin in Sup and AT+Sup groups exhibited a notable decline in comparison to Con and AT groups (P<0.005), as well as a substantial increase in the levels of SOD (P=0.001) and GPx (P<0.005), and TAC (P<0.005) was observed.Conclusion: Diabetes is associated with elevated MDA levels, which are reduced by aerobic training and supplementation. Furthermore, the administration of a training intervention and the utilization of a supplement have been demonstrated to elevate the levels of SOD, TAC, and GPx.