Metabolic, muscle damage and heart rate responses in brazilian jiu-jitsu matches of varied duration

The aim of this study was to analyze physiological responses in Brazilian jiu-jitsu (BJJ) athletes during matches of varied duration. To this end, 10 athletes (age: 29±5 years old, body mass: 77.5±6.3 kg, body fat: 10.0±5.2%, systematic BJJ practice: 10±2 years) were analyzed in matches of varied duration (2-min, 5-min, 8-min and 10-min). Blood collection was performed to determine energetic demands, hormonal responses and muscle damage. The main results showed that a longer duration of combat generated higher lactate (p<.001) and glucose (p=.004) concentrations. However, when the data were corrected for the effort time, higher lactate concentrations (p<.001) and higher heart rates (p<.001) were found in shorter duration combats. No changes were observed concerning insulin (p=.870), triglycerides (p=.219), total cholesterol (p=.170), albumin (p=.060) and urea (p=.772) values. For markers of muscle damage, no alterations were detected for creatine kinase (p=.401). However, evidence of muscle damage was found, as increased lactate desidrogenase (p=.012) and creatinine (p=.002) concentrations were observed, particularly in the matches of a longer duration. Thus, it is concluded that different combat times have a direct influence on the physiological, hormonal and metabolic responses