PurposeThe present study aims at investigating the physiological response and technical-tactical parameters in Brazilian jiu-jitsu competition.MethodsThe 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.ResultsThe 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.ConclusionIt 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.

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The world is currently facing a serious coronavirus pandemic (COVID-19). This novel coronavirus is a new virus for which effective drugs and vaccines have not yet been developed. Amateur and professional athletic events around the world have been stopped, and teams and athletes have had to adopt social withdrawal measures, interrupting their training and preparation routines for competitions. Given this alarming scenario, this article aims to alert athletes to the importance of maintaining a conditioning routine during this confinement period.

BackgroundBrazilian jiu-jitsu is a grappling combat sport that has intermittency as its core element; in other words, actions of high, moderate and low intensity are interspersed during matches, requiring a high level of conditioning to support optimal levels of performance for the total match time. The athletes perform from four to six matches during a day of competition, and this number may increase if the open-class competition, which is held parallel to the competition by weight class, is considered. This systematic review examined the physical and physiological profiles of Brazilian jiu-jitsu athletes.MethodsOnly scientific researches dealing with the major fitness components of Brazilian jiu-jitsu athletes (i.e. body composition and somatotype, aerobic and anaerobic profiles, muscular strength and power) and using accepted methods that provided relevant practical applications for a Brazilian jiu-jitsu athlete’s fitness training and/or performance were included in the current review. A computer literature search was carried out of the PubMed, ISI Web of Knowledge, SportDiscus and Scopus databases (up to January 2016).ResultsThe database research generated 205 articles. After the application of inclusion and exclusion criteria, 58 studies were included for the present systematic review. A total of 1496 subjects were involved in all the selected investigations.ConclusionsBody fat is generally low for these athletes and the mesomorphic component is predominant. The different studies showed VO2max values between 42 and 52 mL/kg/min, and it seems that aerobic fitness does not discriminate among Brazilian jiu-jitsu athletes of different competitive levels. There is a lack of scientific studies that have investigated anaerobic responses both in lower and upper limbs. Maximal dynamic, isometric and endurance strength can be associated with sporting success in Brazilian jiu-jitsu athletes. Although decisive actions during Brazilian jiu-jitsu matches are mainly dependent on muscular power, more specific studies are necessary to describe it. Studies involving the female sex should be conducted. In addition, further research is needed to analyse whether there are differences between sex, belt ranks and competitive level, and among the different weight categories for different variables.

Summary Objective The goal of this study was to evaluate the influence of high‐intensity interval training (HIIT) on anthropometric variables in adults afflicted with overweight or obesity and to compare the effects with those of moderate‐intensity continuous training. Methods A computer literature search was performed for HIIT intervention studies that evaluated anthropometric variables in adults afflicted with overweight or obesity. Results Of the 857 articles retrieved in the electronic search, 48 met the inclusion criteria. The analyses demonstrated that HIIT was effective in decreasing body mass (−1.45 kg [95% CI: −1.85 to −1.05 kg]), body mass index (−0.44 kg m−2 [95% CI: −0.59 to −0.30 kg m−2]), waist circumference (−2.3 cm [95% CI: −3.1 to −1.4 cm]), waist/hip ratio (−0.01 [95% CI: −0.02 to −0.00]), body fat percentage (−1.29% [95% CI: −1.70% to −0.87%]) and abdominal visceral fat area (−6.83 cm2 [95% CI: −11.95 to −1.71 cm2]). When considering equalization between the two methods (energy expenditure or workload matched), no differences were found in any measure except body mass (for which HIIT was superior). Conclusions High‐intensity interval training and moderate‐intensity continuous training results were similar, particularly when equalization between the two methods was considered. Thus, HIIT can be used as a secondary method for the treatment of obesity in adults.

Background: Existing research suggests that irisin increases in response to exercise in humans. However, results are controversial and a majority of the studies lack a control group. The present study aimed to analyze the effects of both one-bout, and three-week intense resistance training on physical fitness (body composition and strength) and serum irisin levels when compared to a control group.

The aim of this study was to analyze performance, time structure, technical actions, and perceptual responses in Brazilian jiu-jitsu athletes during a simulated competition. For this purpose, 10 athletes were analyzed in a simulated competition (4 matches of 10 minutes). Physical tests and scales of the perception of effort and recovery were applied. The matches were recorded for the purpose of technical-tactical analysis and to determine the time structure. The main results show that in the simulated competition, reaction time (F(2.5,17.6) = 2.7; p = 0.087; η² = 0.28) and flexibility (F(7,63) = 1.5; p = 0.172; η² = 0.15) were unchanged across the matches. An analysis of variance showed a significant difference for grip endurance using the kimono (F(2.0,15.9) = 8.1; p = 0.004; η² = 0.50), which was not confirmed by the Bonferroni test. Jump height indicated postactivation potentiation after match 2 (F(7,63) = 3.5; p = 0.003; η² = 0.28). The maximal isometric handgrip strength in the dominant hand (F(3.2,28.6) = 2.9; p = 0.049; η² = 0.24) and in the nondominant hand (F(7,63) = 3.8; p = 0.002; η² = 0.30) showed a decline after matches 3 and 4. Although these data indicate the onset of fatigue, the effort/pause ratio of the matches was not altered (F(3,12) = 0.6; p = 0.624; η² = 0.13). The perceptions of effort (F(3,27) = 0.9; p = 0.469; η² = 0.09) and recovery (F(1.9,17.0) = 2.4; p = 0.125; η² = 0.21) and the degree of fatigue reported (F(1.5,13.8) = 0.5; p = 0.588; η² = 0.05) did not change during the simulated competition. Thus, it may be concluded that the execution of successive matches causes a decline in maximal isometric handgrip strength. No changes in the time structure of the matches or in the perceptual responses were observed.

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