What does BJJ ask of your body?
More strength than engine, as far as the research can tell. Andreato and colleagues reviewed 58 studies of Brazilian jiu-jitsu athletes, 1,496 people in all. Aerobic power, measured as VO2max, ranged from 42 to 52 ml per kilogram per minute in men, much like other grappling sports, and in the authors' words it seems that aerobic fitness does not discriminate between athletes of different competitive levels.
Strength looked different. In two of the studies, advanced or elite athletes had a heavier one-rep max on the bench press than less advanced ones, and the review notes that Olympic wrestlers show the same gap on the bench press and in the squat. Maximal handgrip was, in the authors' words, not high: 48 to 57 kg force in elite or experienced athletes. But tests of how long athletes could hang from a gi, or how many chin-ups they could do holding one, can, in the authors' word, discriminate athletes of different experience and level, and the authors call muscular endurance of the grip and trunk one of the most critical components of the sport. Their conclusion uses a careful verb: maximal, isometric and endurance strength can be associated with success.
Power is the open question. The authors argue that the moments that decide a match, the guard passes, sweeps and takedowns, depend on power in the arms and the legs, and in one study experts jumped higher than novices. Yet when power was measured on a bench press throw, advanced and less advanced competitors did not differ.
Two limits matter before you build a programme on this. The review is a collection of profiles, athletes measured and compared at one point in time; studies that follow athletes through training are, in the authors' word, incipient. So they show what stronger, higher-level grapplers look like, not that lifting made them win. And they are studies of men. Only two of the 58 included women, both measuring body composition alone; the review found no data on women's maximal strength or aerobic fitness, and its authors call studies of women indispensable.
"Can be associated" is as far as the BJJ review goes on strength. It is a good reason to take strength seriously if you roll, not a promise that a heavier bench press wins matches.
What does boxing ask of your body?
An engine and power, both. Chaabène and colleagues reviewed the physical and physiological profile of amateur boxers. Boxers of both sexes, they found, need a high level of cardiorespiratory fitness, to meet the demands of a bout and to recover faster between rounds. International boxers showed high peak and mean anaerobic power. Strength in both the arms and the legs was, in the review's words, one of the keys to success, and because punches are brief, very dynamic actions, high-level boxing needs well-developed power in both. The evidence on isometric strength is limited, but the studies available link it to high-level performance.
Kickboxing and Muay Thai
Kicking styles look much the same, with less research behind them. Slimani and colleagues reviewed 30 kickboxing studies and reported moderate to high cardiorespiratory fitness, high anaerobic power at every level, and a need for power in the arms and legs alike, since kickboxers punch and kick. They also found that no study had measured a kickboxer's one-rep max, and none had looked at sex, age or weight class in strength.
One small study shows what separated winners. Among high-level male kickboxers at a national championship, the 10 tested winners threw a medicine ball further than the 10 tested losers, a median of 4.6 metres against 4.1, while their jump heights did not differ significantly. The largest gaps, though, were in a mental toughness questionnaire.
Muay Thai has even less. When 10 male athletes fought a simulated match wearing a portable gas analyser, their oxygen uptake and heart rate stayed above their anaerobic threshold for the whole match, and the authors concluded that training should cover both the aerobic and the anaerobic systems. And when 15 Muay Thai and 15 BJJ competitors from one Polish club, all men aged 18 to 30, took the same fitness tests, the BJJ group scored higher on grip strength, grip relative to body weight, pull-ups and a bent-arm hang. That fits the split this page is about, though 30 people from one club is a small window.
Where do grapplers and strikers split?
James and colleagues went looking for what separates better fighters across combat sports, to build a picture of the ideal MMA athlete. Their systematic review found 23 studies, from five of the eight sports searched, that compared men aged 17 to 40 at different competitive levels. A number of strength, power and anaerobic measures distinguished higher- from lower-level athletes; greater aerobic power generally did not. The differences were less clear among athletes within the same grade.
The two families appear to split in a telling way. In the authors' reading, the better grapplers are stronger across the board, from heavy, slow efforts to light, fast ones, driven by greater maximal strength, while the better strikers may stand out less on maximal force and more on light, high-speed actions. Longer anaerobic efforts seem to mark out successful grapplers, shorter ones successful strikers. This page draws on the review's abstract.
MMA asks for both. In a study of 29 male semi-professional and amateur MMA competitors, the higher-level group had a greater one-rep max squat relative to body weight, 1.84 against 1.56 times body mass, and produced more power, force and speed in loaded jump squats at every load. Their bench press was higher, but not quite significantly, and an isometric pull from mid-thigh did not differ.
Chaabène's boxers need high cardiorespiratory fitness to last the rounds, yet across combat sports James found that aerobic power rarely separated the better athletes from the rest. Our reading: for strikers, the engine is the price of entry, and strength and power are where better fighters pull ahead. For grapplers, the research leans further still towards strength.
Do martial artists need to run?
Running, a bike, a rower and skipping are the usual cross training for martial arts. In our view, running is optional for grapplers and useful for strikers, and the reasons are in the studies above.
Grapplers. Aerobic fitness seemed not to separate BJJ levels, though Andreato's team note it can matter for recovering between and during matches. Every VO2max in their review came from a treadmill test or an estimate from a running or step test, never from the mat, and no study had measured aerobic demand during a match. Of the few interval-training studies in combat sports, one used BJJ movements; the rest used generic means such as running. If you roll hard through the week, mat time builds the conditioning you use. A run adds most when you compete, or when your lungs give out before your technique does.
Strikers. Boxers need high cardiorespiratory fitness for the bout and for recovery between rounds, and a simulated Muay Thai match ran above threshold from start to finish. Class builds much of that. Running is one way to build more; skipping, a bike or a rower are others.
Running and lifting mostly coexist. Schumann and colleagues pooled 43 studies of healthy adults: adding aerobic training did not blunt gains in maximal strength or muscle size, and running and cycling did not differ. Explosive strength was the exception, more so when both shared a session. The science is set out in running and lifting.
What should the gym add for each style?
Strength training for martial arts starts from what class already does. Class does much of the conditioning, so in our view the gym's job is the part class does least: heavy strength, and for strikers, speed under load. The table sets out what each style's research links with success, what class already trains and what that leaves for the gym.
| Style | What research links with success | What class already trains | What the gym adds (our view) | Source and sample |
|---|---|---|---|---|
| BJJ and grappling | Upper-body maximal strength (bench press) and grip endurance with the gi. Aerobic fitness seemed not to separate levels. In wrestlers, the squat too. | Holding grips, pulling, framing and trunk endurance, round after round. | Heavy strength for the upper and lower body. Some forearm and grip work, more if your grip goes before the rest of you. | Andreato 2017: 58 studies, 1,496 athletes; the strength data are from men. |
| Boxing | High cardiorespiratory fitness; strength and power in arms and legs; isometric strength, on limited evidence. | Rounds of skipping, pads, bag and sparring: hard conditioning. | Strength in the legs and arms, plus fast power work: jumps and throws. | Chaabène 2015: a review of amateur boxers; the fitness finding covers both sexes (abstract). |
| Kickboxing and Muay Thai | Moderate to high aerobic fitness, high anaerobic power, power in arms and legs. Kickboxing winners threw a medicine ball further. | Punches, kicks and knees in rounds, on pads, bag and in sparring. | Leg power as much as arm power, on top of heavy strength. | Slimani 2017: 30 studies. Slimani 2016: 20 high-level men. Crisafulli 2009: 10 men. |
| MMA | Lower-body maximal strength and loaded jump power. Across combat sports, aerobic power rarely separated levels. | Both of the above: grappling and striking rounds. | Heavy lower-body work and loaded jumps, plus the grappler's upper-body strength. | James 2017: 29 men. James 2016: 23 studies, men aged 17 to 40. |
Grapplers
Strength first. The BJJ link is with upper-body maximal strength, and the wrestling link adds the squat. The 2026 ACSM position stand, an overview of 137 systematic reviews in healthy adults, found strength gains were greater with loads of 80% of one-rep max or more, for 2 to 3 sets. In our view, that means a few heavy sets of a press, a pull and a squat or hinge, not another circuit: rolling is the circuit. Grip and trunk endurance rank high in the BJJ review. Its authors say the forearms should be covered in training, because athletes in competition reported more fatigue there than anywhere else, though how best to train them is still a question for future studies. Rolling already trains holding on, so in our view dedicated grip work earns the most when your grip goes before the rest of you.
Strikers
Strength and speed. Boxers need strength and power in the arms and legs; the kickboxing winners threw further; striking research favours light, fast actions. The same ACSM stand found power gains were greater with moderate loads of 30 to 70% of one-rep max, Olympic-style lifts and a fast lifting phase. In our view, a striker's gym week pairs a few heavy sets with fast work: jumps, throws and quick lifts. If you kick, the legs need that work as much as the arms; the kickboxing review found the demands similar in both. Where each goes in the week and in the session is in boxing and weights.
MMA
Both. The higher-level MMA competitors separated most clearly on lower-body strength and loaded jump power. In our view, an MMA lifting week leans on heavy lower-body work and jumps, keeps the grappler's upper-body strength and leaves most conditioning to class.
The strongest general evidence for lifting at all comes from injury research across mixed sports: a 2014 meta-analysis of 25 trials and 26,610 people, some of the trials in adolescents, found strength training cut sports injuries to under a third, while stretching had no effect. If something already hurts, see a physio or a doctor before you load it.
When should you lift around classes?
That is a scheduling question, and two pages answer it. BJJ and lifting covers where heavy pulling and grip work go in a week of rolling. Boxing and weights covers lifting around pads, bag and sparring, and what changes when you kick. An MMA week needs both. For a day of several matches, see tournament weekend; for other sports and classes in one week, see crossovers; and for every sport we cover, see Sports.
Go to You and, under SPORTS STACK, tap + ADD. BJJ, boxing, kickboxing and MMA are in the list of sports. Muay Thai goes in as Kickboxing: search for it, or type it under Other. With Pro or during your trial, your coach plans around what you already do instead of on top of it. More in Add a sport or a class.
In the sport's settings, choose Fixed days if your club runs a timetable, where each day you pick is one session a week, or Flexible to let the app pick the days. Set your usual session length too. Turn on Add performance training to tell your coach you want to get better at the sport, not just fit training around it: it creates a goal for that sport, which counts towards your three goals. More in Sport settings.
Jumps, throws and lifts you have not done before are easier to follow with a picture: exercises are shown as clean illustrations: the movement on a plain background, with nothing extra. The team is exploring video and moving images. More in Exercise illustrations. If the rack is taken mid-session, DO IT LATER moves that exercise to the end of the session where it can be moved; if your gym lacks the kit, with Pro or during your trial your coach suggests swaps that train the same thing. Both change only the session you are doing. More in Swap an exercise mid-session.
If a hand, knee or shoulder flares up after sparring or rolling, open LIMITATIONS on Home and set how serious it is, from Cleared to Serious. With Pro or during your trial, your plan is rebuilt around what you report. Your coach is a training tool, not a medical service, and tells you to see a physio or a doctor. More in Report an injury.