1. The Flailer. Honestly, you’re not sure if he’s rolling with you, or just executing a very poorly choreographed break-dancing routine. This is a person, male or female, who is very new to jiu jitsu, and who has decided that the best defense is MOVING ALL THEIR LIMBS VERY RAPIDLY in any direction they can. Sometimes flailers are good practice to roll with, because their erratic movement makes you think and you have to work hard to control them and not get sucked into their spazzyness. Just know, every time you roll with them you risk getting elbowed in the face, poked in the eye, knee’d someplace you don’t want to be knee’d, or worse.

2. The Flexer. The Flexer is the opposite of the Flailer. Unlike the Flailer, the vast majority of Flexer types are males. Rather than protecting himself through frantic motion, this type will protect himself by tensing every muscle to the max, trying to move as little as possible, and turning himself into a kind of stationary boulder. Armbars are not a good bet, because you know he’ll have his arms sucked tightly into his chest. Fortunately for other jiu jitsu players, this type is much easier to deal with than the flailer, because he will usually get tired and gas out quickly. (Keeping everything flexed to the utmost is hard). He might be stronger and be able to lift more at the gym than you, but you, being a good jiu jitsu player, can just go around him and avoid this contest in the first place.

3. The Petri Dish. The Petri Dish is not to be confused with the normal sweaty people you roll with at every jiu jitsu class. Sure, everyone sweats, and sometimes people can smell pretty bad when they sweat. It’s just part of the jiu jitsu experience. The Petri Dish takes it up several notches by not merely soaking his gi uniform in sweat, but also subsequently stuffing said gi into the bottom of his gym bag, where it percolates and festers until he unrolls it again, ready to inflict germ warfare on his unsuspecting victims. The bacteria that’s been breeding in his repeatedly-unwashed gi is probably something the CDC should be informed about. If he takes side control on you, you might have to suppress the urge to throw up. Fortunately, at some point everyone at the school will get sick of this, and yell at him to wash his gi already.

4. The Dead Fish. This person neither flails nor flexes. They don’t do much of anything, in fact, but maybe passively flop over onto one side. The Dead Fish is frequently a bigger, stronger male who misinterprets a request to “go easy” or “go medium” as a request to “do nothing at all and do an impression of a training dummy.” This is both annoying and condescending, as jiu jitsu requires a reciprocal commitment of effort, and you need the other person to do something so you can work off of their movements. Personally, since I’m a girl, I probably encounter more Dead Fishes than guys, as I apparently put forth an (entirely inaccurate) impression of fragility. (I’m not asking you to take my head off when you roll with me, by the way. Just work with me a little).

5. The Talons. Obviously, Talons is a person who is blessed with strong, healthy fingernails and toenails, and who thinks it’s great to just let their nails do their own thing and prune them very rarely. Although I’ve never encountered it because I’ve never met a girl who’s crazy enough to try and have long nails while doing jiu jitsu, conceivably there could be a female Talons as well. After you roll with Talons, you’ll inevitably discover a bunch of small scratches on yourself in weird places, which tend to get infected, because, after all, they were made with FINGERNAILS.

6. The Talker. Is he trying to stall, or is he just really sociable? Maybe he has a very solitary job and is starved for human companionship. All you know is that you can’t get into the flow of the roll because you have to stop every few seconds to respond to something he’s said. The Talker will also be apparently oblivious to your polite efforts to stifle further conversation, even if you’ve been answering all his assertions with “Hm.” Granted, everyone makes occasional comments to one another as they roll. This is normal, and to insist on absolute silence while rolling seems pretty uptight. If you’re trying to carry on a running discourse about the latest crisis in the Middle East while rolling, however, it might be time to shut your piehole.

7. The Loud-Breather. It’s good to breathe in jiu jitsu, and holding the breath is totally a beginner’s mistake. I also teach yoga, so you don’t even need to tell me about the benefits of deep breathing. Loud-breathers, on the other hand, accompany their respiration with a variety of sound effects. Some Loud-Breathers are prone to shuddering, spastic breaths, and pained, hissing exhales when you put pressure on them. They sound like they might have a heart attack or diarrhea at any moment, and like to broadcast when their next move is coming with a dramatic inhale. While rolling with a Loud-Breather, you might find yourself wondering if you should actually stop the roll, just in case they really are in cardiac distress. The other, far worse, kind of Loud-Breather is one whose breath patterns are vaguely pornographic and inappropriate, which isn’t great in a sport where you spend a lot amount of time sitting on other people’s heads.

8. The Perfume Counter. The Perfume Counter is the opposite of the Petri Dish. His gi looks clean, to the best of your knowledge, but you don’t really know because the only thing you can smell within a 10-foot radius of him is the entire bottle of cologne he dumped on himself before class. Girls can also be perfume counters, but most females know that scents should be subtle, not aggressive. It’s nicer to smell some kind of cologne or body spray than to smell unwashed gi, but after you finish rolling with him, you still smell like him, and your gi still reeks even after you take it home.

9. The “New Guy.” The “New Guy” is not really a new guy- hence the quotation marks. This is a person, new to the school, who feigns perfect innocence of the ways of grappling, and then deftly back-steps to pass your guard and crushes you. Now in his side control, it dawns on you with a shock of recognition that there’s absolutely no way this guy has “never” grappled before. You spend the next several minutes getting back the position you lost because you had assumed the guy was a beginner. I’m not sure what possesses guys to lie about their grappling experience- maybe some misguided sense of ego? The need to win by any means necessary? At any rate, be prepared to meet someone like this at some point in your jiu jitsu lifetime.