Leverage, and the promise made to the smaller person

The promise goes like this: jiu-jitsu is the art in which the smaller person can win, because leverage and technique count for more than size and strength. A newcomer tends to meet it before meeting a technique.

It is easy to find in print. Gracie Barra, an organisation of jiu-jitsu schools, keeps what it calls a Legacy Wall on its About Us page, and its entry for Helio Gracie reads: "A master of technique who refined Jiu-Jitsu for smaller practitioners, proving that leverage and skill can overcome strength and size." That is the organisation's sentence about its own lineage, and we quote it as the organisation's statement and nothing more. It is a fair sample of how the promise is worded: proving, overcome, strength and size.

This piece treats that sentence as a claim and asks what the sport's own documents do with it. It names no match and no result, for the reason our article on the early UFC tournaments gives: outcomes from the period the promise leans on circulate in versions that cannot be checked against a primary record.

What follows in this section is plain mechanics and it is ours, not a finding from any study of grappling.

A lever is a rigid thing turning about a pivot. A force applied far from the pivot balances a larger force applied close to it, and the price is distance: the long end has to travel further than the short end moves. Nothing is created. The lever converts a small force over a long path into a large force over a short one.

Grappling is full of this. A grip at the wrist turns an arm about the shoulder more easily than a grip at the elbow does. Our piece on base, posture and structure describes structure as bone carrying force so that muscle does not have to, which is the same economy seen from the other side.

The mechanics also set a limit that the slogan leaves out. A lever multiplies the force you bring to it, so more force in still means more force out. And levers are not issued only to the smaller person. The larger opponent has limbs too, usually longer and heavier ones, and can learn exactly the same technique. Leverage explains how a force can be made to go further. It does not say whose force wins.

If technique reliably cancelled size, a competition would have no reason to weigh anybody. The two rule makers this site reads most often, the IBJJF and ADCC, weigh everybody who enters a weight division.

The IBJJF's no-gi weight list, linked from its 2026 World No-Gi Championship page, divides adult and masters men into nine divisions. The first eight carry a maximum weight, taken in uniform: rooster at 122.6 pounds, light feather at 136.0, feather at 149.0, light at 162.6, middle at 175.6, medium heavy at 188.6, heavy at 202.0 and super heavy at 215.0. The ninth, ultra heavy, is printed with no maximum weight. Adult and masters women have eight divisions, from rooster at 103.0 pounds to heavy at 169.0, and a super heavy division with no maximum.

The arithmetic is ours: each men's limit sits between 13 and 13.6 pounds above the one before it. On this list the federation does not match two adult men across more than about thirteen pounds until the last division.

It enforces the lines, too. The event page says the official weigh-in happens immediately before the first fight, that only one attempt is allowed, and that athletes are disqualified if they weigh in heavier than their division's limit. The rule book says the same thing from the other side: clause 8.3.1 allows each athlete onto the official scale once.

ADCC draws fewer lines and still draws them. Its weight class page gives the World Championship and Trials five men's classes, under 65.9, 76.9, 87.9 and 98.9 kilograms and over 99, and three women's classes, under 55.0, under 65.0 and over 65.0. For its other tournaments the same page prints eight adult men's classes, from under 60 kilograms to over 100.

Both documents also keep a division with no weight line at all, and this is where the promise survives inside the rules.

The IBJJF weight list has a final row, open class, marked free for adults. ADCC's table ends its men's column with a line that reads Absolute (Open) Class. The IBJJF rule book uses both words: clause 4.4.1 refers to the ultra heavyweight and absolute divisions, and clause 5.9 to the open class.

Look at how the door is hung, though. At the 2026 No-Gi Worlds, the event page says athletes who placed first, second or third in their weight division are eligible to register for the open class, with adult black belts as the stated exception, all of whom may enter. For most belts, then, a competitor must first place among people their own size. For juvenile blue and purple belts even the open class is split in two, a light bracket from rooster to light and a heavy bracket from middle to ultra heavy.

ADCC's rules page, for its part, anticipates what an open bracket produces. Its scoring clause for the mount provides that where there is a size difference between the fighters in an absolute match and the top fighter cannot get both knees to the mat, the referees decide whether there is enough control to score. A rule set does not write that sentence unless it expects very different bodies to meet.

So the sport has not legislated the promise away. It has made it an optional extra: a separate bracket, entered by choice, alongside the weighed divisions and not in place of them.

The promise is often argued from early mixed martial arts, and the only description of that format we rely on is a regulator's. In its 2002 proposal for mixed martial arts rules, the New Jersey State Athletic Control Board wrote that it had been hesitant to sanction events, and gave as examples that the sport "generally did not divide contestants into weight classes, had contestants participate in several matches on the same evening and did not provide time limits on either round or bout length".

The first rule the board then proposed, N.J.A.C. 13:46-24A.1, divides mixed martial artists into nine weight classes, from flyweight under 125.9 pounds to super heavyweight over 265.

Our article on those tournaments argues that they were a demonstration and not a proof: a small bracket, self-selected entrants, conditions that the Unified Rules no longer permit. The same caution applies here. A format without weight classes showed that a smaller competitor could win. It could not show how often, or against how much extra weight, and the regulated sport that followed did not keep the format long enough for anybody to find out.

The direct test of the promise would measure skill and body mass together and report how much of one offsets how much of the other. In the searching done for this piece we did not find a peer-reviewed study that does that for grappling. That is a statement about our search, not about everything ever published.

What we could read is adjacent. Andreato, Diaz Lara, Andrade and Branco published a systematic review of the physical and physiological profiles of Brazilian jiu-jitsu athletes in Sports Medicine - Open in 2017, covering 58 studies and 1,496 subjects and centred, by its own account, on athletes in the gi. Its conclusions include this sentence: "Maximal dynamic, isometric and endurance strength can be associated with sporting success in Brazilian jiu-jitsu athletes." The supporting finding it reports is that bench press one-repetition maximum was greater in advanced or elite athletes than in non-advanced or non-elite ones.

That is a comparison between groups at different competitive levels, not between opponents of different sizes, and an association is not a mechanism. But it points one way. Among people who compete, the more successful groups were not the weaker ones.

The review also says what is missing. It asks for studies across different weight categories, in its words "feather to heavy, as well as absolute". The division in which the promise is actually put to the test is one the authors list among the things still to be studied.

Put the documents side by side and the promise changes shape. This last part is our argument.

Weight classes exist because size matters. No federation explains its weight list in those words, but a list of limits thirteen pounds apart, enforced by disqualification at the scale, is not something a sport builds around a variable it believes technique has cancelled. The strong form of the promise, that size does not matter, is contradicted by the table a competitor registers against.

The form that survives is comparative. Skill is worth something measured in weight: a trained person can give away some amount of mass to a less trained one and still prevail, and the amount grows with the gap in skill. Nothing in the rule books contradicts that. The open class is that claim offered as an invitation.

What nobody has published is the exchange rate. How many kilograms a year of training is worth, whether the rate holds at the heavy end, whether it differs with and without the gi: in the material read for this piece, there is no number for any of it. Anyone who quotes one is guessing.

The promise is still worth making in its narrower form. It says that the smaller person's disadvantage is real and that training reduces it. Both halves are needed, and a version that keeps only the second half is asking a lever to do something a lever does not do.