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Updated: Jan 25, 2026

A Real-World High-Intensity Interval Training Protocol for Cardiorespiratory Fitness Improvement
Published on: February 22, 2022
Aerobic interval training improves maximal oxygen uptake and reduces body fat in grapplers
1Department of Sociology and Political Science, Norwegian University of Science and Technology, Trondheim, Norway - karsten.ovretveit@ntnu.no.
Background:
Despite regularly engaging in high-intensity grappling, Brazilian jiu-jitsu (BJJ) athletes have a moderate maximal oxygen uptake (V̇O2max). The aim of this study was to evaluate the efficacy and feasibility of high-intensity aerobic interval training as an accessory to BJJ training for improvements in V̇O2max.
Methods:
Twelve active male BJJ practitioners (age: 30.3±4.0 [SD] years; height: 183.0±5.3 cm; body mass: 82.7±8.3 kg; body fat: 11.9±3.8%) with 5.6±5.8 years of experience and a training volume of 9.9±4.6 hours·week-1 were randomly allocated to either a training group (TG) or control group (CG). The TG incorporated two high-intensity aerobic interval training sessions·week-1 comprising four 4-minute intervals at 85-95% of maximal heart rate (HRmax) separated by 3-minute active breaks at 70% of HRmax.
Results:
After six weeks, the TG increased their V̇O2max by 8±3% (95% CI=3.84, 12.73; P=0.04; ES=0.64), from 52.7 to 56.8 mL·kg-1·min-1. This was accompanied by a 1±1% reduction in absolute body fat (95% CI=-0.13, -2.2; P=0.04; ES=0.64). No changes in V̇O2max (P=0.12) or body composition (P=0.34) were detected in the CG.
Conclusions:
These findings reveal compelling short-term effects of low-volume high-intensity aerobic interval training on V̇O2max and body composition in active BJJ athletes. There may be a ceiling effect in terms of developing V̇O2max in supine, intermittent grappling sports, making alternative approaches to aerobic conditioning particularly relevant for this athlete population.
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