Adenilson Targino de Araújo Júnior

Effects of High-Intensity Blood Flow Restriction Exercise on Muscle Fatigue

Abstract Strength training combined with blood flow restriction (BFR) have been used to improve the levels of muscle adaptation. The aim of this paper was to investigate the acute effect of high intensity squats with and without blood flow restriction on muscular fatigue levels. Twelve athletes (aged 25.95 ± 0.84 years) were randomized into two groups: without Blood Flow Restriction (NFR, n = 6) and With Blood Flow Restriction (WFR, n = 6) that performed a series of free weight squats with 80% 1-RM until concentric failure. The strength of the quadriceps extensors was assessed in a maximum voluntary isometric contraction integrated to signals from the surface electromyogram. The average frequency showed significant reductions in the WFR group for the vastus lateralis and vastus medialis muscles, and intergroup only for the vastus medialis. In conclusion, a set of squats at high intensity with BFR could compromise muscle strength immediately after exercise, however, differences were not significant between groups.

Treinamento de sobrecarga muscular não afeta o diâmetro das principais veias dos membros inferiores em mulheres adultas com insuficiência venosa

Physical exercise can promote benefits in the functionality of the venous system. However, in the strength training context, contraindication concerning its practice is observed, since it can be related to worsening of venous dysfunctions. OBJECTIVE: To analyze the effects of resistance exercises practice on venous diameter of physical inactivity women with chronic lower limb venous insufficiency. METHODS: Twenty-two women with age between 21 and 58 years (34.27 ± 12 years) were randomized divided in two groups: experimental (n = 12) and control (n = 10). The resistance training was carried out over a period of 16 weeks and the venous diameter measurements were determined at the left lower limb Great and Small saphenous veins by a color Eco- Doppler. Two-way ANOVA was used to determine the modifications in veins diameter between groups and training moments (pre and post) (p < 0.05). RESULTS: Statistically significant alterations were not found in smaller saphenous vein diameter (upper, medium and lower points: p = 0.80; 0.32 and 0.20, respectively), great saphenous vein on leg level (p = 0.17; 0.74 and 0.96) and great saphenous vein on thigh level (p = 0.57; 0.67 and 0.52). CONCLUSION: Resistance exercise practice can be considered a treatment or intervention since it does not promote changes on the venous diameter of the venous system of women with chronic lower limb venous insufficiency.

Effects of Backpack Load and Trekking Poles on Energy Expenditure During Field Track Walking

This study evaluates the effects of the use of backpack load and trekking poles on field track walking energy expenditure. Twenty male volunteer pole walkers (age: 22.70±2.89 years; body mass: 77.90±11.19 kg; height: 1.77±0.06 m; percentage of body fat: 14.6±6.0%) walked at a self-selected pace on a pedestrian field track over a period of more than six months. Each subject was examined at random based on four walking conditions: non-poles and non-load, with poles and non-load, non-poles and with load, with poles and with load. Heart rate, oxygen uptake and energy expenditure were continuously recorded by a portable telemetric system. Non-load walking speed was lower during walking with poles when compared with no poles ( p ≤0.05). Oxygen uptake, energy expenditure and heart rate varied significantly across different conditions. Our results suggest that the use of trekking poles does not influence energy expenditure when walking without an additional load, but it can have an effect during backpack load walking. Moreover, our results indicate that the use of trekking poles may not be helpful to lower the exertion perceived by the subjects when walking with an additional load.

Acute effect of a fight of Mixed Martial Arts (MMA) on the serum concentrations of testosterone, cortisol, creatine kinase, lactate, and glucose

The aim of this study was to analyse the serum concentrations of testosterone (T), cortisol (C), lactate (LAC), creatine kinase (CK) and glucose (GLU) on mixed martial arts (MMA) athletes, before and after a fight. We divided 20 MMA athletes into two groups of 10 fighters each, according to the result of a fight, and were then evaluated four times: 24 hours before (-24h), one hour before (-1h), immediately after (0h) and 24 hours after the fight (+24h). It was observed: a significant decrease in T and T/C between moment -24h and 0h and a subsequent increase between the moment 0h and +24h and a reverse behaviour in variables C, LAC and GLU (p<0.0001); a decrease in CK between moment -24h and -1h and an increase between moment -1h and +24h (p<0.0001); and differences between winners and losers T levels, in moments -24h, -1h, 0h and +24h (p = 0.009 e p < 0.001, p = 0.005 e p = 0,001, T and C, respectively), in T/C in the moments -24h and 0h (p=0.006 and p=0.001, respectively) and in GLU levels (p<0.0001) in the moment 0h. Therefore, it seems that an MMA fight leads to metabolic stress and muscle damage, regardless of the result of the fight. The coaches have now more biochemical and hormonal references and indicators in response to an MMA fight.