***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Objectives The present study aim ed to evaluate the effects of using hyperbaric oxygen therapy during post-training recovery in jiu-jitsu athletes . Methods Eleven experienced Brazilian jiu-jitsu athletes were investigated during and following two training sessions of 1h30min . Using a cross-over design , the athletes were r and omly assigned to passive recovery for 2 hours or to hyperbaric oxygen therapy ( OHB ) for the same duration . After a 7-day period , the interventions were reversed . Before , immediately after , post 2 hours and post 24 hours , blood sample s were collected to examine hormone concentrations ( cortisol and total testosterone ) and cellular damage markers [ creatine kinase ( CK ) , aspartate aminotransferase ( AST ) , alanine aminotransferase ( ALT ) , and lactate dehydrogenase ( LDH ) ] . Moreover , the rating of perceived exertion ( RPE ) and recovery ( RPR ) scales were applied . Results Final lactate [ La ] values ( control : 11.9 ± 1.4 mmol/L , OHB : 10.2 ± 1.4 mmol/L ) and RPE [ control : 14 ( 13–17 a.u . ) , OHB : 18 ( 17–20 a.u . ) ] were not significantly different following the training sessions . Furthermore , there was no difference between any time points for blood lactate and RPE in the two experimental conditions ( P>0.05 ) . There was no effect of experimental conditions on cortisol ( F1,20 = 0.1 , P = 0.793 , η2 = 0.00 , small ) , total testosterone ( F1,20 = 0.03 , P = 0.877 , η2 = 0.00 , small ) , CK ( F1,20 = 0.1 , P = 0.759 , η2 = 0.01 , small ) , AST ( F1,20 = 0.1 , P = 0.761 , η2 = 0.01 , small ) , ALT ( F1,20 = 0.0 , P = 0.845 , η2 = 0.00 , small ) or LDH ( F1,20 = 0.7 , P = 0.413 , η2 = 0.03 , small ) . However , there was a difference between the two experimental conditions in RPR with higher values at post 2 h and 24 h in OHB when compared to the control condition ( P<0.05 ) . Conclusions Thus , it can be concluded that OHB exerts no influence on the recovery of hormonal status or cellular damage markers . Nonetheless , greater perceived recovery , potentially due to the placebo effect , was evident following the OHB condition It is speculated that anaerobic metabolism is the predominant source of energy in karate kumite . However , no experimental proof is currently available . The metabolic cost and fractions of  aerobic and anaerobic energy of  karate kumite fighting were investigated . Ten male nationally or internationally ranked karateka [ means ( SD ) age 26.9 ( 3.8 ) years , height 1.80 ( 0.08 ) m , mass 77.2 ( 12.8 ) kg ] performed two to four fights scheduled and judged like a championship . Oxygen uptake was measured continuously with a portable spirometric device . Blood lactate was determined immediately before , and minute by minute after , each fight . Aerobic , anaerobic alactic and anaerobic lactic energy were calculated from oxygen uptake during the fight ( VO2 ) , the fast component of the post-fight oxygen uptake ( VO2PCr ) above resting values and changes in blood lactate concentration ( Net-BLC ) , respectively . Altogether , 36 fights lasting 267 ( 61 ) s were analysed . The referee ’s decisions caused an activity-to-break ratio of approximately 2:1 . VO2 , VO2PCr , and Net-BLC per fight were 165.3 ( 52.4 ) ml.kg−1 , 32.2 ( 7.2 ) ml.kg−1 and 4.2 ( 1.9 ) mmol.l−1 ; the overall energy cost above rest was 334.3 ( 86.3 ) kJ per fight . Fractions of aerobic , anaerobic alactic , and lactic energy sources were 77.8 (5.8)% , 16.0 (4.6)% , and 6.2 (2.4)% , respectively . The results indicate a high metabolic rate in karate kumite . However , the acyclic activity profile implies that aerobic metabolism is the predominant source of energy and there is anaerobic supplementation , mainly by high-energy phosphates Breath-by-breath O2 uptake ( $ $ \dot{V}_{{{\text{O}}_{2 } } } $ $ , L min−1 ) and blood lactate concentration were measured before , during exercise , and recovery in six kata and six kumite karate Word Champions performing a simulated competition . $ $ \dot{V}_{{{\text{O } } _ { { 2 { \text{max } } } } } } , $ $ maximal anaerobic alactic , and lactic power were also assessed . The total energy cost ( $ $ V_{{{\text{O } } _ { { 2 { \text{TOT } } } } } } , $ $ mL kg−1 above resting ) of each simulated competition was calculated and subdivided into aerobic , lactic , and alactic fractions . Results showed that ( a ) no differences between kata and kumite groups in $ $ \dot{V}_{{{\text{O } } _ { { 2 { \text{max } } } } } } , $ $ height of vertical jump , and Wingate test were found ; ( b ) $ $ V_{{{\text{O } } _ { { 2 { \text{TOT } } } } } } $ $ were 87.8 ± 6.6 and 82.3 ± 12.3 mL kg−1 in kata male and female with a performance time of 138 ± 4 and 158 ± 14 s , respectively ; 189.0 ± 14.6 mL kg−1 in kumite male and 155.8 ± 38.4 mL kg−1 in kumite female with a predetermined performance time of 240 ± 0 and 180 ± 0 s , respectively ; ( c ) the metabolic power was significantly higher in kumite than in kata athletes ( p ≤ 0.05 in both gender ) ; ( d ) aerobic and anaerobic alactic sources , in percentage of the total , were significantly different between gender and disciplines ( p < 0.05 ) , while the lactic source was similar ; ( e ) HR ranged between 174 and 187 b min−1 during simulated competition . In conclusion , kumite appears to require a much higher metabolic power than kata , being the energy source with the aerobic contribution predominant To determine differences in maximal strength and muscle power output of the arm and leg extensor muscles , peak and mean power during a modified st and ing crank-arm Wingate test , running speed , muscle extensibility , and anthropometric markers between elite and amateurs wrestlers according to the weight classes system ; 92 male wrestlers were assigned into 6 groups according to their body mass ( light , middle and heavy weight ) and their competitive level ( elite and amateur ) : Light Weight ( body mass ranged between 55 and 68 kg ) in elite ( LWE , n = 18 ) and amateur ( LWA , n = 15 ) level ; Middle Weight ( body mass ranged between 68 and 84 kg ) in elite ( MWE , n = 18 ) and amateur ( MWA , n = 19 ) level ; and Heavy Weight ( body mass ranged between 84 and 100 kg ) in elite ( HWE , n = 10 ) and amateur ( HWA , n = 12 ) level . Elite wrestlers were older ( 8–12 % ) , had more training experience ( 25–37 % ) , fat-free mass ( 3–5 % ) , maximal strength in absolute and relative terms ( 8–25 % ) , muscle power ( 14–30 % ) , mean and peak power during crank-arm Wingate testing in absolute and relative terms ( 13–22 % ) , jumping height ( 8–17 % ) as well as grip ( 6–19 % ) and back strength ( 7–20 % ) compared to amateur wrestlers . However , no differences were observed between elite and amateur groups in height , body mass index , percentage of body fat , hamstring extensibility and running speed . The present results suggest that the higher absolute and relative values of maximal strength , muscle power , and anaerobic metabolism , explained in part by the differences in lean mass and neural activation patterns , will give elite wrestlers a clear advantage during the most frequently used techniques in Olympic wrestling Twenty sedentary male university students were r and omly assigned to an experimental or a control group . The experimental group trained the knee extensors of one leg by producing 30 isometric extension maximal voluntary contractions ( MVC ) per day , three times per week for 8 wk . After 8 wk of training , extensor MVC in the trained leg increased 32.8 % ( P less than 0.05 ) , but there was no change in vastus lateralis maximal integrated electromyographic activity ( IEMGmax ) . The most important finding was that the degree of hamstring coactivation during extension MVC decreased by approximately 20 % ( P less than 0.05 ) after the 1st wk of training . Less pronounced adaptations occurred in the untrained leg : extension MVC force increased 16.2 % ( P less than 0.05 ) , hamstring coactivity decreased 13 % ( P less than 0.05 ) after 2 wk of training , and vastus lateralis IEMGmax was unchanged . The same measures in legs of the control group were not changed during the study . There were no changes in flexion MVC , biceps femoris IEMGmax , or the degree of quadriceps coactivity during flexion MVC in either leg of the control or experimental group . A reduction in hamstring coactivity in the trained and untrained legs indicates that these muscles provide less opposing force to the contracting quadriceps . We conclude that this small but significant decrease in hamstring coactivation that occurs during the early stages of training is a nonhypertrophic adaptation of the neuromuscular system in response to static resistance training of this type Abstract da Silva , BVC , de Moura Simim , MA , Marocolo , M , Franchini , E , and da Mota , GR . Optimal load for the peak power and maximal strength of the upper body in Brazilian Jiu-Jitsu athletes . J Strength Cond Res 29(6 ) : 1616–1621 , 2015—We determined the optimal load for the peak power output ( PPO ) during the bench press throw ( BPT ) in Brazilian Jiu-Jitsu ( BJJ ) athletes and compared the PPO and maximal strength between advanced ( AD ) and nonadvanced ( NA ) athletes . Twenty-eight BJJ athletes ( 24.8 ± 5.7 years ) performed the BPT at loads of 30 , 40 , 50 , and 60 % of their 1 repetition maximum ( RM ) in a r and omized order ( 5-minute rest between BPTs ) . The PPO was determined by measuring the barbell displacement by an accelerometer ( Myotest ) . The absolute ( F = 7.25 ; p < 0.001 ; effect size [ ES ] = 0.21 ) and relative intensities were different ( F = 7.11 ; p < 0.001 ; ES = 0.21 ) between the AD and NA . There was also a group and intensity interaction effect ( F = 2.79 ; p = 0.046 ; ES = 0.10 ) , but the differences were centered around the AD group , which achieved higher values using 40 % ( p = 0.001 ) and 50 % of the 1RM ( p < 0.001 ) than the PPO with 60 % of 1RM . The AD athletes presented with higher 1RM than NA ( p ⩽ 0.05 ; ES = 1.0 ) , but there was no difference ( p > 0.05 ) in the PPO ( 30–60 % 1RM ) . A polynomial adjustment indicated that the optimal load was ∼42 % of 1RM for all groups and subgroups ( R 2 from 0.82 to 0.99 ) . Our results suggest that there can be ( 1RM ) differences between AD and NA BJJ athletes ; however , there is no difference in the muscle power between the AD and NA groups . Additionally , ∼42 % of 1RM seems to be the optimal load for developing maximal power using the BPT for the BJJ athletes CONTEXT Although caffeine is one of the most commonly used substances in combat sports , information about its ergogenic effects on these disciplines is very limited . PURPOSE To determine the effectiveness of ingesting a moderate dose of caffeine to enhance overall performance during a simulated Brazilian jiu-jitsu ( BJJ ) competition . METHODS Fourteen elite BJJ athletes participated in a double-blind , placebo-controlled experimental design . In a r and om order , the athletes ingested either 3 mg/kg body mass of caffeine or a placebo ( cellulose , 0 mg/kg ) and performed 2 simulated BJJ combats ( with 20 min rest between them ) , following official BJJ rules . Specific physical tests such as maximal h and grip dynamometry , maximal height during a countermovement jump , permanence during a maximal static-lift test , peak power in a bench-press exercise , and blood lactate concentration were measured at 3 specific times : before the 
    Output:
    
Conclusions Body 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 .