Energy System Contributions in Upper and Lower Body Wingate Tests in Highly Trained Athletes.

PURPOSE: This study compared the energy system contributions and relationship between mechanical and energy system variables in upper and lower body Wingate tests (WAnT) in judo athletes. METHOD: Eleven male judo athletes (18 ± 1 years, 174.3 ± 5.3 cm, 72.6 ± 9.9 kg, 11.8 ± 1.7% body fat) attended two laboratory sessions to perform two WAnT (upper and lower body) and two incremental tests (upper and lower body). The energy contributions of the oxidative, glycolytic, and phosphagen (ATP-PCr) systems were estimated based on oxygen consumption ( V˙O2 ) during WAnT, delta of lactate, and the fast phase of excess V˙O2 , respectively. RESULTS: The upper and lower body presented similar results of oxidative (21 ± 4% vs 23 ± 3%) and ATP-PCr system contributions (29 ± 6% vs 32 ± 5%). The glycolytic system contribution (50 ± 5% vs 45 ± 4%) was higher in the upper body. The variance of mechanical variables in upper body was explained by glycolytic (R2 = 0.49-0.62) and oxidative systems (R2 = 0.44-0.49), whereas the variance of mechanical variables in lower body was explained by ATP-PCr (R2 = 0.41-0.55) and glycolytic systems (R2 = 0.62-0.94). CONCLUSIONS: During WAnT, the glycolytic system presented the major energy contribution, being higher in the upper body. Moreover, mechanical and energy system variables presented a distinct relationship when comparing upper and lower body WAnT.

Effects of walk training with self-selected intensity on biochemical markers and anthropometric variables in women with obesity.

To evaluate the effects of 12-weeks of walk training with self-selected intensity on lipid profile and anthropometric variables in women with obesity. Forty-eight women volunteers with obesity were randomly assigned into two training groups: self-selected walking group (SSWG; n=25) and control group (CG; n=23). There was improvement in biochemical markers only in the SSWG post-intervention (p<0.05), however no changes were verified in anthropometric variables (p>0.05). This study demonstrates that walking at self-selected intensity improved the lipid profile in women with obesity.

Brazilian Jiu-Jitsu Simulated Competition Part I: Metabolic, Hormonal, Cellular Damage, and Heart Rate Responses.

The aim of this study was to analyze physiological responses in Brazilian jiu-jitsu athletes during simulated competition. To this end, 10 athletes (age: 28 ± 4 years, body mass: 81.8 ± 7.4 kg, body fat: 13.0 ± 4.8%, systematic practice: 11 ± 4 years) were analyzed in simulated competition (4 matches of 10 minutes). Blood samples were taken to assess energy demand, hormonal responses, and cell damage. Additionally, the heart rate variability (HRV) response was analyzed. The main results show that in simulated competition, during the last matches, athletes had lower lactate (p < 0.001), epinephrine (p < 0.001), norepinephrine (p < 0.001), and insulin (p = 0.002) concentrations. Increases observed in creatine kinase (p < 0.001), aspartate aminotransferase (p < 0.001), alanine aminotransferase (p = 0.007), and creatinine (p < 0.001) seen, especially, in the last matches are indicative of possible cell damage. The HRV reflected a decrease in the RR medium (average of the normal R-R intervals) (p = 0.001) during the competition. Thus, it is concluded that successive matches from competition generate a gradual decrease of adrenergic and glycolytic activities, which is accompanied by a gradual increase in cell damage markers and decrease in the RR medium of the HRV.

Physiological and Technical-tactical Analysis in Brazilian Jiu-jitsu Competition.

PURPOSE: The present study aims at investigating the physiological response and technical-tactical parameters in Brazilian jiu-jitsu competition. METHODS: The study included 35 male Brazilian jiu-jitsu athletes (adult category, body mass: 80.2 ± 13.0 kg), graded from white to brown belt, during combats fought at regional level. Twenty-two fights were analyzed in terms of technique and time structure. Blood glucose, lactate and maximal isometric grip strength were determined before and after the fights. The rate of perceived exertion was also assessed after the fight, using the 6-20 Borg rating. The fights were recorded and the following variables were determined: the exertion/pause ratio and subjective intensity of actions, categorized between low and high intensity. RESULTS: The results indicated that during Brazilian jiu-jitsu fights, the glycolytic pathway is only moderately activated (lactate before: 4.4 (4.0 - 4.6) mmol/L, after: 10.1 (8.0 - 11.3) mmol/L; glucose before: 112.4 ± 22.3 mg/dL, after: 130.5 ± 31.0 mg/dL). The exertion during the fight resulted in significant reductions in handgrip strength (right hand grip before: 45.9 ± 10.3 kgf, after: 40.1 ± 9.5 kgf; left hand grip before: 44.2 ± 11.1 kgf, after: 37.0 ± 10.2 kgf). The athletes rated the fight as hard: 15 (13 - 15). Effort/pause ratio was 6:1, while high-intensity actions lasted approximately 4 s, resulting in a low/high intensity? ratio of 8:1. CONCLUSION: It is recommended that coaches direct the training loads to simulate the energy demand imposed by the competitive matches, activating moderately the glycolytic pathway. Moreover, the time structure of combats can be used to prescribe both physical and technical-tactical training.