Effects of an aerobic training program on oxidative stress biomarkers in bulls

The aim of this study was to evaluate the effect of aerobic training (16 weeks - T1 and 24 weeks - T2) on oxidative stress biomarkers. To this end, GSH, GSH-peroxidase (GSH-Px) and catalase (CAT) activity were analysed in plasma. Nine bulls (3-4 years), were included in this work. The exercise training protocol was performed in a track ("taurodromo") three days per week for 24 weeks and consisted of 400 m warming up, 1200 m to 4-5 m/s, two minutesʹ resting, 1200 m to 4-5 m/s and, finally, 400 m walking. The results reflected that GSH-Px activity was higher at T1 (6.18 ± 0.45) than at baseline (T0; 2.31 ± 0.08) while the GSH level (2.98 ± 0.37) was lower vs. T0 (14.59 ± 3.40). Moreover, there were significant increases in GSH-Px (18.23 ± 1.36) and CAT (2.52 ± 0.04) activities and the recovery of basal values in GSH (11.75 ± 2.84) in T2. In conclusion, the type of training carried out in this study involved two well-defined stages: (i) a period of perturbation, followed by (ii) adaptation. The former stage was characterised by the induction of oxidative stress manifested as a decrease in the GSH, and the latter (T2) by the recovery of this non-enzymatic antioxidant.