Msc Ashkan Koushki, Professor Hamid Aghgaalinegad, Professor Reza Gharakhanlou3,
Volume 0, Issue 0 (11-2019)
Abstract
Aim: Optimal performance is the ultimate goal of athletes. The purpose of this study was to compare the effects of different high-intensity interval training (HIIT) protocols on athletic performance and metabolic adaptations. Methodes: The participants were divided into 4 groups: High-Intensity Running Training (HIITRUN), Sport-Specific High-Intensity training (HIITSPORT), Combined Training (HIITSPORT+RUN), and Control. The measured indicators included: maximum running speed in the 30-15 test (VIFT), maximum oxygen consumption (VO2max), the SWFT index and throws in the sport-specific wrestling fitness test, fatigue index, and maximal lactate. Comparisons between dependent variables were performed using a two-way analysis of variance (group and time) with repeated measures. Result: Significant changes in (VIFT) and VO2max were observed in HIITSPORT+RUN (P<0.05) and HIITRUN (P<0.05) compared to pre-training, control, and HIITSPORT. The fatigue index showed a significant decrease in HIITSPORT+RUN and HIITRUN compared to pre-training in the other groups. HIITSPORT+RUN (P<0.05) showed the greatest improvements in the SWFT index compared to HIITRUN and HIITSPORT, and the time-group interaction confirmed its superiority. Post-exercise lactate levels in HIITSPORT+RUN (P<0.05) were lower than in HIITRUN, but no significant difference was observed in the time-group interaction (P<0.05). The difference in maximal lactate levels before and after exercise in HIITSPORT+RUN (P<0.05) was lower compared to HIITRUN. HIITSPORT+RUN (P<0.05) showed better performance in the SWFT compared to pre-training. The fatigue index decreased in all training groups except for the control (P<0.05). Conclusion: the combined HIIT approach of sport-specific training and running is the most effective method for improving wrestlers' performance and metabolic adaptations.
Dr Malihe Aveseh, Dr Maryam Koushkie Jahromi, Dr Javad Nemati, Dr Saeed Esmaeili Mahani,
Volume 21, Issue 25 (9-2023)
Abstract
Lactate has been recently considered as a signaling factor involved in metabolism. The aim of this study was to investigate the role of lactate entrance into the brain on endurance training-induced adaptations in lipid oxidation.
24 male rats (age: 8 weeks, weight: 197 ± 21 g) were divided into control (C), trained (T), and traind+4-CIN (T+4-CIN, which experienced the inhibition of lactate entrance into the brain during exercise). All animals performed a single session of acute endurance exercise following their 12-weeks training protocol. Free fatty acids (FFA) and triglyceride content in plasma and adipose tissue and cAMP and Inositol triphosphate (PI3) content in epididymal fat were measured immediately after acute exercise using ELISA and were compared among the groups by one-way analysis of variance (ANOVA).
Acute exercise significantly increased lactate concentration in cerebrospinal fluid (SCF) in both T and T+4-CIN compared to the C group. Lactate concentration was slightly lower in T + 4-CIN compared to the T. Immediately after acute endurance training, a significant decrease of 61 and 31% in plasma triglyceride levels, a significant decrease of 39 and 26% in adipose tissue triglyceride levels, a significant increase of 125 and 56% in plasma FFA levels, a significant increase of 217 and 125% increase in FFA plasma levels, a significant increase of 87 and 41% in adipose tissue cAMP levels, and a significant increase of 90 and 49% in adipose tissue inositol triphosphate levels was observed in the T and T+4-CIN compared to the control group, respectively (all P < 0.01). Plasma triglyceride and adipose tissue levels in the 4-CIN + training group were significantly higher and plasma and adipose tissue FFA levels were significantly lower (all P < 0.05) than the values found in the T group. In conclusion, the results of the present study showed that lactate can be effective on endurance training-induced adaptations in lipid oxidation due to its action in the brain.
