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Weight cutting in MMA: A scientific approach to fixing the problem

Aldo vs. McGregor

Weight cutting in MMA is a problem. Actually, It’s a problem in any sport that puts fighters into weight classes. The problems range from the health and safety concerns of the fighters, as we saw recently with the death of a fighter in the Philippines, to fighters attempting to gain a competitive advantage. 

But ultimately, it’s bigger than that. It's a cultural problem. Weight cutting is generally accepted, even though EVERYONE knows it’s dangerous and stupid. The problem is that everyone is doing it, so everyone must continue to do it. After watching a glut of weigh-ins due to UFC running three shows in three days last week, I’ve given the matter a lot of thought. 

First, let me support what I'm about to say by giving you some background about me personally.

As a former MMA fighter and high school wrestler, and current BJJ competitor, I’ve spent a lot of my life cutting weight.  Heck, I even did two bodybuilding shows where I actually cut more weight than any of those previous endeavors. Over the last two decades, I’ve been a wrestling coach, personal trainer, and nutritionist. I’ve helped many normal people lose weight safely, and also helped many high level athletes take their bodies to the extreme. I’ve experienced enough weight cutting to have learned some tricks of the trade, and also learned what’s not going to work. 

I also spent a few years working at an eating disorder facility where I saw firsthand just what awful effects both short and long-term “weight cutting” can have. It was an incredibly eye opening experience. One of the myths about weight cutting is that there is a healthy way to do it, but there is no perfectly healthy way to cut weight. Some ways are safer than others, but whichever method a fighter chooses, it will have consequences. 

I don’t want to bore people with a biology lesson, but to put it simply, weight cutting has two phases; body weight loss and dehydration. Note I said body weight, and not exclusively fat. The goal is to lose as much body fat as possible while sparing muscle, but it’s next to impossible to do one with out the other, naturally.  Phase one of losing bodyweight usually starts about 12 weeks out from a fight and comes in the form of changing nutritional habits and exercising more.  The fighter simply cleans up their diet and reduces calories, and the weight comes off. 

The second phase, dehydration, is the dangerous part.  A fighter will most commonly use water manipulation to suck every ounce of both interstitial and intracellular fluid out of their bodies. This can be done through use of the sauna, steam room, exercise, diuretics, and a few other sneaky things like mineral manipulation. Here’s the problem; you’re not only dehydrating your muscles, but you’re also dehydrating your heart (since it’s a muscle) as well as your brain. This is incredibly dangerous. 

Why? Fluid acts as a padding for your brain. If you're lacking that padding, head impact can have a much more detrimental effect. Fighters sacrifice literal brain size by cutting fat (the brain is almost entirely fat), and now they are depleting the cranial fluid.  Since fighters eat and rehydrate before fighting, this is generally mitigated, but it’s impossible to fully rehydrate in 24 hours, so without a doubt, most fighters are going into the cage with their brain less than 100% re-padded. For most fighters, they believe this is an appropriate risk level for their sport.  I recall cutting weight for fights that final week and feeling like I was in a fog. It was noticeable too as people around me kept asking me why I was spacing out. My brain was starving!

Also, your heart can’t beat properly if dehydrated. This is how people die: your heart goes into arrhythmia or stops all together due to the lack of minerals, which were flushed out during the dehydration. Basically, you’ve reduced your intravascular blood volume. Most people have around 6-7 liters of blood circulating at all times, and since blood is mostly water, this is a big problem. The heart tries to compensate for the lack of blood by pumping more, which causes irregular blood pressure as it beats faster and faster, and eventually fails. This is most likely what occurs when people die in a sauna. 

So now we know why weight cutting is dangerous, but what do we do? 

There have been a lot of options floated around, but none have come to fruition, such as same day weigh-ins and creating more weight classes. The UFC, more specifically WADA and USADA, have outlawed the use of IV rehydration in an attempt to keep guys from risking the huge weight cut.  The idea is obviously that if rehydration is more difficult, then perhaps the massive weight cut won’t be attempted. This may work, but ultimately, it doesn’t change the problem that guys are still going to cut a dangerous amount of weight and just try and rehydrate orally. Personally, I’ve rehydrated both with IVs and without, and never noticed any difference, other than I had to have my EMT buddy steal me saline and hook me up, which was unpleasant. At fight time, physically, I felt the same.

There’s actually data that supports the claim that oral rehydration is superior. In fact, the quickest most effective way to get lost electrolytes and other minerals back in to the blood is by rinsing the mouth with a solution and spitting it out. There’s a bunch of info you don’t need to know about gastric emptying involved. If someone wants to make a million dollars, go invent the perfect mouth rinse for fighters to use between rounds. 

It’s often suggested that more weight classes be used, but I don’t like this idea at all. For one, it waters down the championships but that’s not nearly as important as the safety of the fighters.  The real reasons why more weight classes is a bad idea is because it will actually encourage more weight cutting. I’ve seen it happen. 

Each year, the people in charge of collegiate wrestling regulations adjust the weight classes. They do this for various reasons, but basically it’s done to better facilitate the current population. For example, suppose last year there were more wrestlers registered at 180 pounds than ever before. That would indicate that perhaps the sport needs a weight class adjustment, and maybe the addition of a 187 pound class instead of jumping from 180 to 195. This makes sense, but what usually happens is that athletes get greedy. Now, a wrestler that used to make 195 starts to think that maybe he or she could stretch it even further and make that new 187 pound class. So the athlete that was cutting from 205 to 195 is now going to cut an extra 7 pounds.  Good coaching can offset some of this, but it doesn’t always happen. 

At the lower classes, it happens even more as there is often only three or four pounds between a weight class. That seems like nothing to these competitors. When an athlete that walks around at 125 who cuts to 117 only has to drop three more to make 114, and only 4 more beyond that to make 110, for a total of only 15 pounds total, that’s incredibly enticing. People think, “Well, that’s only 15 pounds. Some of these big boys cut 30!”  Right, they do, but 30 off a 235 pound person is actually cutting nearly the same percentage of total body weight as the 125 pound person cutting 15 pounds. 

In this example, the smaller person lost 12% of their body weight while the bigger guy lost about 13%.  Take into account the fact that the big guy has a lot more muscle and fat to drain water from, and you realize that the little guy’s brain is probably in way worse shape than the big guy’s.  Amateur wrestling implemented the hydration testing before the season to determine the lowest weight class in which a wrestler can compete to keep things like the above example from happening, but MMA is a different beast.

I'd like to point out quickly that this past weekend, we saw two main events end the exact same way: flash KO.  This is not to diminsh the punching power of Frankie Edgar or Conor McGregor, but Chad Mendes and Jose Aldo looked smaller and more depleted than usual IN THE CAGE than in the past. This was the first time either man has attempted to rehydrate without IVs, and both suffered KOs from punches that each has eaten dozens of times in the past. It's purely speculation, but was that a pair of coincidences...or perhaps each was suffering from a dehydrated brain and could not withstand the impact?

Since more weight classes does not seem to work (at least in amateur wrestling where weigh-ins occur sometimes just an hour prior to competition), I’d like to propose something different: fewer weight classes.

Simply put, if the weight class gap widens, less people will attempt the cut. Of course, there are masochists out there who would go for it, but my guess is that it would stem the tide of dangerous weight cuts.

So now, where do we make the classes? How do we decide where to put the markers? It’s simple: use science. There would have to be a study of the human population to see where they are needed. (It may already exist.) First, determine the average size of the population and chart it out from there.  It would be a bell curve. 

I’m just guessing, but most adult men are probably somewhere around 150-160 pounds (at least in developed countries), with fewer at 200, and even fewer at 300 pounds, just as fewer are at 125 and still fewer are 100 pounds. Obviously, as a species, we are evolving to be larger, but we can determine the current bell curve for today. Put more weight classes in the middle and fewer towards the ends of the charts. 

There are of course other factors to examine. For instance, we don’t need to know the average of the entire population, just those involved in fighting. Eight-year-olds and 80-year-olds can be left out. Just look at men and women (separately) likely to be involved, so from ages 18-50 (since Bellator still exists). Also, look at people most likely to fight. There aren’t many African pygmies in the UFC, so we can ignore that population. 

Once we determine the bell curve, we then make the weight classes which doesn't have to be every ten pounds. Since as we discovered above, percentage of body weight is also important thus the gaps should be larger toward the heavy end and smaller toward the light end. I have not done the studies or even tried to find the data, but as a jumping off point for discussion, here is my best guess at the new weight classes.

- Men: 125, 132, 142, 155, 175, 205, 265
- Women: 115, 125, 140, 160

This would create ten total champions: six for men and four for women.

Each year, the weight classes could swing a pound or two in any direction. They don’t have to be set in stone. The names of the divisions and champions would stay the same. There would have to be some fine-tuning of this method, but it could be implemented, and it would make a difference. 

The other option, of course, would be for fighters to just stop doing it, but we all know that’s not happening.