clock menu more-arrow no yes

Filed under:

The details of nutrition & weight cutting for MMA with George Lockhart

New, comments

George Lockhart explains some misconceptions and myths about weight cutting in MMA, and gives insight on the important considerations for an MMA fighter's nutrition and weight cutting needs.

Courtesy of George Lockhart

This is part two of the interview Steph Daniels and I conducted with George Lockhart (part one). Here he delves into a little more detail about the science of nutrition and weight cutting, where people go wrong and more. While it has been kept reasonably simple to allow the maximum amount of people to understand, some of the concepts are only touched upon and not explained in detail. To that end there is a glossary at the end of the article explaining many of the terms used, and how they apply in the context of the article.

Caloric Intake

I’ve dealt with people who believe calories in vs calories out is all you need to know about weight loss. If that was true I really wouldn’t have a job. I’d just tell people to eat less calories.

One thing I tell people is that a significant percentage of the calories in protein are actually used by your body in order to digest those calories. With carbohydrates your body consumes almost 100% of those calories. You don’t think of it that much, but if you eat 2,000 calories of protein and 2,000 calories of carbs you’ll see two totally different people.

You see people with different body types as well. Some people can go and eat a ton of food without gaining a pound, but someone like me gains weight from eating really easily. That’s because of our different hormonal responses to the foods. When I eat them I have a more abundant hormonal response and my body stores a lot more, which allows me to gain weight more efficiently. If I affect the hormones of an individual, that gives me the ability to dictate the size, muscle mass and fat mass an individual has.

You get fighters who have been pigging out during the start of camp, taking in 5,000 or 6,000 calories a day, and then mid-way through the camp it's time to get ready to fight and they'll cut down to 2,000 or 2,500 calories. Now initially they lose weight, but the body will start learning to work off of those 2,500 calories, so they'll stop losing weight and they can even start gaining weight. What you want to do instead is keep the calorie count high, so that towards the end of the camp when you do cut those calories, you lose the weight.


When people talk about nutrition one of the fallacies a lot of people believe is that our body’s primary source of fuel is carbohydrates. The truth is that our body’s primary source of fuel is fat. We use the metabolic equivalent  to find out how many calories an individual burns during a workout. During a workout we actually find out as a percentage how much of the burned calories are carbohydrates versus fat.

Let’s say that I burned 1,000 calories while jogging, versus burning 1,000 calories while lifting heavy weight. Lifting heavy weights is more anaerobic, meaning without oxygen, so your body is going to burn more carbohydrates in that 1,000 calories. If they’re jogging they’ll burn more fat. Now, we want to replace carbohydrates during the regular fight camp, but we don’t want to replace the fat. 

Based on the formulas we have about their lean body mass and the metabolic equivalent, we know how many calories the individual burned and what percentage of those calories was carbohydrates. If an individual holds 400g of carbohydrates in their muscles, and the workout they performed burned 200g of carbohydrates, they still have 200g of carbohydrates to burn in their muscles. That allows us to target anaerobic workouts until their body has used up the glycogen in their muscles. At that point we stop doing anything anaerobic. Instead we do more aerobic exercise to burn more fat.

Your body’s primary source of fuel is fat. That should be a primary source of calories in my diet. For the longest time the FDA recommended we eat 6-11 servings of carbohydrates a day. I’m sitting wondering why you would do that when the average person doesn’t do anything anaerobic anyway. The only time your body uses carbohydrates as a primary source of fuel is when you’re anaerobic, and if you’re never anaerobic there’s no purpose in it.

I think ketogenic diets are a bad idea for fighters, though. I have fighters who do 2, 3 or 4 days of training when they’re anaerobic. They need those carbohydrates. Muscle needs glycogen and water to help fuel it. If you take away the carbohydrates, you take away the water that muscle holds via glycogen. If you’re not using all of your muscle and they’re not firing optimally, your performance is going down. The number one thing for a fighter is performance. If you’re so worried about making weight that your performance goes down, then you’re in the wrong weight class.

Weight Cutting

The amount of water weight someone can cut and regain is related to the amount of lean muscle tissue an individual has. When people hear lean muscle mass, they think being 200lbs with 10% bodyfat means they’re 180lbs of muscle. The truth of it is between your internal organs and your bones and stuff, only about 40% of that is actual lean muscle tissue, so we use a formula to find the actual lean muscle tissue.

We convert that into kilograms, and then multiply that number by 13 to get the amount of glycogen your muscles can hold. Your lean muscle tissue needs 13 grams of glycogen per kilogram and one gram of glycogen needs 3 grams of water. Once I know how much glycogen someone can hold in their muscle that tells me how much weight they will regain from glycogen and water, because about 70-75% of muscle is water.

Now I use that information to load the muscles back up the correct amount. If you take any more than that in you get spillage and you’ll become lethargic and feel heavy during the fight. A lot of people just carb up, carb up, carb up, but you have limited storage space, you know?  Everything is mathematical.

Your liver also holds glycogen, and that’s used to fuel the brain. Different types of carbohydrates are going to fuel that, and we want to keep the brain fuelled throughout the weight cut, because if you have full muscles but your brain isn’t getting glucose, you’re going to crash. If you get irritable when you haven’t eating in a while, that’s because your brain needs fuel, even if your muscles are full. With a weight cut I want to make it so your brain is fuelled, but your muscles need glycogen.

There’s a lot of even more detailed stuff in those algorithms, things like the potassium-sodium ratios and the calcium and magnesium ratios to make sure the muscles contract. Sometimes if you have too much calcium the muscles will contract too quickly and you can blow your wad. If you have too much magnesium, you can go forever but you’re slow as hell, you lose your pop.

During a weight cut we cut the amount of glycogen in the muscles. We know exactly how much the body holds and so we know exactly what type of workout they need to do. A lot of my guys actually make weight early. When you’re getting low on calories you want each calorie to be burned as efficiently as possible. If you eat a sugar cube your body will absorb that very quickly and you’ll be hungry again and need more fuel again quickly.

Fat is burned the slowest out of any macronutrient. So the week of the weigh-ins we decrease the amount of carbohydrates and increase the amount of fats. Because your calories are restricted you want all of your calories to last as long as possible and fat lasts longest. As you get closer to the actual weigh-ins we cut back on fat and start incorporating frozen fruits. Something I use a lot is pineapple. The reason is dietary fibre will hold water. If I put a bunch of water into a bowl and the lettuce is brown and wilted, within the next day it will absorb the water via osmosis and be good lettuce again. When guys are near the end of their weight cut they are cutting back on how much water they take in, so they don’t have to worry about the body absorbing the water. That means we can give them the fruit, which is going to help fuel the brain.

Ten percent of our metabolism comes from breaking down food. That’s about 200 calories from a 2,000 calorie diet. Eating solid food keeps you feeling fuller as well, so I want the fighters eating solid food rather than consuming smoothies and drinks as much as possible close to a weigh in.

We try to keep the carbohydrate restriction down to a short period of time to mitigate things like muscle catabolism, hypoglycaemia and drops in lutenizing hormone. A lot of fighters cut carbs two or three weeks out, but our process only takes up to four days, and we're only really cutting carbs for two of those. We do it so quickly that by the time the body starts to react you've already made weight.

Liver Glycogen vs Muscle Glycogen During Weight Cuts

When it comes to replenishing the glycogen stores in the liver, which fuels the brain, we give it fructose. The fructose will get glucose into the bloodstream and fuel the brain without creating a hormonal response of insulin. Without the insulin response, less of it goes to your muscles, but of course your body will obviously still send some of it to the muscles. Even when we are out of glycogen your body will still be creating glycogen via glyconeogenesis.

Hydration and Water Retention

Sometimes you might get on the scale and feel really wobbly and overweight, and then the next day you get on and everything feels really tight and you look great, but you still weigh the same. That’s because your body will hold water inside the cell, or outside the cell between it and the skin. When the water is in the cell, that’s when you feel tight.

The sodium and water inside the cell causes contraction. There’s so much more to it than I can go into, but basically that creates an electric charge which causes the contraction, which is a great thing. Now, if the water is on the outside, what happens is you feel heavy. Now the kicker is, it’s not just about loading the water back up, it’s about putting it back into the right place.

Aldosterone is a hormone that affects the amount of sodium. A 185lbs guy holds about 75,000mg of sodium at a given time. Now your body can excrete, use and hold this whenever it feels it needs to. If we start depleting sodium, which a lot of guys do a couple of weeks out, your body is going to start releasing aldosterone, which will make you hold water just like if you were eating tons of salt. So we have to keep aldosterone in check and we have to keep vasopressin in check.

Vasopressin is an anti-diuretic hormone that controls the rate your body expels water. If it wasn’t for vasopressin, if you were in the desert you would sweat out and die within hours. When your blood becomes thin your body increases your levels of vasopressin.

What some fighters will do is cut five pounds, and they’ll plan to lose the other five the next day, but overnight the body notices the blood is thin and releases vasopressin. The next day they’ll be in the sauna dying wondering why they’re not sweating. They have the water, but the signal has already been sent to the body to release the vasopressin, and once that happens it’s very difficult to create sweat, but there are some things you can do.

I’ll do whatever the fighter wants, so if they want to cut weight overnight like that we will, but I’ll tell them how to do it more effectively. The way you do that is instead of keeping the room really warm, which you would think helps, you actually keep it really cold. What happens is the viscosity of the blood thickens because of the low temperature, which decreases the amount of vasopressin, so the next day the pores stay open and you sweat a lot easier.


The process of reloading is so important, it’s as important if not more important than the weight cut. If you don’t make weight you lose 20% of your purse. If you fight like crap and lose your fight you lose half your purse. I tell fighters to look at it like this: Your body wants all of these macronutrients, but it’s like having an upside down filter, and if you just pour as much as you can into that filter you plug it up. These guys get so bloated so quickly because they eat and drink so much at a time.

We don’t actually eat and drink at the same time. If they’re eating they’re not drinking, and if they’re drinking they’re not eating. We have to wait for the digestive enzymes to be created through the saliva glands before guys should eat, and to do that we have to make sure their fluid levels are optimal.

Your body creates digestive enzymes in your saliva glands. When they’re done cutting weight people try to eat really quickly, but they’re dehydrated so they don’t have those digestive enzymes, which inhibits the body’s ability to digest that food. We have to look at digestion and we have to look at how to get water all the way through the system quickly.

The temperature of the water is something else that is extremely important. Cold water will get through and dump into the small intestinal tract faster than warm water. The kicker is that cold water fills you up faster, so it’s a double edged sword. So in the beginning we get real cold water and flush it with certain basic combinations of macro-nutrients someone will need based on the math we’ve done. After their digestive enzymes are starting to be produced again we switch over to room temperature water, because you can drink more of that without it filling you up.

I hope this doesn’t sound bad, but as you get close to a fight, a fighter’s mind is so fragile. There are so many things that people do because they’re always done them, like the football player who always wears the same jock. For some guys that’s an IV. Sometimes a guy doesn’t need an IV, but he’s always had one. What that means for me is I need to design the muscle loading around the IV. If you have too many electrolytes you can get diarrhea and other negative effects.

A lot of people don’t realize what IVs were designed for; they were designed for the military to rehydrate guys who were dehydrated quick fast in a hurry when a guy just got shot. They’d load an IV and tie it to his shoulder. When I worked at the Marine Corps Martial Arts Center of Excellence we would have a guy go down with heat exhaustion and load him up with an IV tied to his shoulder. That’s because he needs to get back in the fight right there and then, but it’s actually better for the body to reload naturally.


Supplementation can be extremely important, but one thing I always tell people is supplements are meant to supplement your diet. If you eat crap, you’re still just supplementing crap.  Some supplements are extremely important, like BCAAs. BCAAs are like the simple carbohydrate of the protein world; like if I need carbs really fast after a workout I need simple carbohydrates. For protein that’s BCAAs. You can get it through food but it’s actually more optimal to get it through supplementation that’s designed to be absorbed as easily as possible.

I think most people don’t have any idea why they take BCAAs. There’s a lot of science behind it, but I don’t think people really understand why. It’s not so much for the regeneration of muscle tissue as it is for the release of the hormone glucagon. Glucagon is what our body uses to release free fatty acids and restore glycogen. Post workout you’re not really trying to rebuild muscle with your post-workout protein, you’re trying to create a passageway to the cells for the carbohydrates to be introduced. It helps the synthesis of the carbohydrates.


If you’re talking about guys that take stuff like Lasix and illegal substances, I think they’re doing a lot of harmful things to their body. There are so many side effects to that stuff. If you don’t know how your body works you kind of take a pill that does a bunch of stuff to your body to lose the water weight for you, but you have a bunch of side effects.

That being said I give my guys natural diuretics, by which I mean stuff you can actually put on food. Dandelion root is something we give to a lot of guys, depending on how much weight they have to lose. The cool thing about dandelion root is that it’s a potassium saving diuretic, so when you start getting rid of all the electrolytes your body still holds onto the potassium.

Negative Effects of Poor Weight Cutting

One of the biggest reasons I got into this is to help guys cut weight safely. In the Marine Corps you’re told you have to make weight, and they’d do whatever it took. They just know that if they don’t eat anything and deplete water by sitting in a sauna, they’ll lose weight. What they don’t realize is the negative long-term effects of that are. Even if someone has just one bad weight cut, even short-term you’ll get injured more. It can make your bones brittle, mess with your joints and it’s really bad in terms of performance. Sitting in the sauna you’ll see an overweight guy in there, but fat doesn’t hold water, muscle does.

A lot of the time we’ll prep for the weight cut before the cut. We do a pre-cut, a cut, a pre-load and then a load. You have to prep the body for everything. Guys who don’t know that and just sit in the sauna are basically just cooking their insides. It’s like anything else in life. Take insulin resistance, that’s because you spike your insulin again and again. People that have testosterone problems is often because they’ve loaded their body with exogenous testosterone again and again and the body decides it doesn’t need to make testosterone any more.

When you start cutting the body’s water supply off and put it through the strenuous act of sitting in a sauna for hours on end, you’re having a lot of negative effects on your body. I’m not just talking about vasopressin and aldosterone; you’ll see guys weeks after the fight having trouble walking around. Their joints hurt because their body can’t let go of water. They don’t sweat or anything, they literally look like Michelin men. It hurts for them to work out. And those are just the short term effects.


This glossary is written entirely by the author of the article, not George Lockhart. It is designed to give a little more information on some of the terms used in the article that the reader may be unfamiliar with. It is intended to give a very basic introduction to the concepts and explain them as relates to the content of the article. As such there may be some aspects glossed over or not covered. Any inaccuracies contained within this glossary are my fault, not George Lockhart’s.

Aerobic: Aerobic respiration refers to energy produced by the body with the aid of oxygen. It can also refer to exercise during which the body operates within the limits of the oxygen supplied by the lungs and blood, and generates most of the energy required via use of this oxygen. Examples include jogging and many exercises often referred to as 'cardio'.

Anaerobic: Anaerobic literally means without oxygen, or living without air. In this article it primarily refers to anaerobic respiration, which is a process that takes place in cells to create usable energy from nutrients without the presence/use of oxygen. It can also refer to anaerobic exercise, when your body's energy needs are primarily supplied by energy sources not utilizing oxygen, or beyond your body's oxygen supply limits. Examples include sprinting and most strength training.

BCAAs: Branched Chain Amino Acids refers to three amino acids, isoleucine, leucine and valine. Amino acids are primary constituent parts of protein, but unlike most amino acids, BCAAs are metabolized primarily in muscles rather than the liver. As such it is believed that they are more rapidly put to use by the muscles than other types of protein immediately following a workout.

Catabolism: Catabolism in this context refers to the muscle breaking itself down to provide energy, often as a result of insufficient glucose/glycogen being available in the blood. Generally when you hear someone talking about muscle ‘cannibalism,’ it’s referring to muscle catabolism. It can also refer to any process in which the body breaks down larger molecules into smaller molecules.

Diuretic: A diuretic is something which causes the body to expel water in greater amounts than it would under normal conditions. Different diuretics have different methods of action. Abuse of potent diuretics has hospitalized or killed athletes and bodybuilders.

Fructose: Fructose is a sugar primarily derived from fruits and some vegetables. Unlike most other sources of sugar it does not stimulate the pancreas into secreting insulin. As consumed via foods, fructose is significantly less effective than glucose at rapid glycogen restoration of muscles, but is just as effective as glucose at restoring the liver.

Gluconeogenesis/Glyconeogenesis: Gluconeogenesis is a chemical reaction which creates glucose and/or glycogen from non-carbohydrate based sources of energy. The terms Gluconeogenesis and Glycoconeogenesis refer to the same process.

Glucose: Glucose is a sugar which is the primary source of energy for the muscles. Most carbohydrates contain glucose in some form. The body uses glucose to create glycogen to store & provide energy, as well as using it directly as a fuel. The body can also generate Glucose via gluconeogenesis when carbohydrates are unavailable.

Glycogen: Glycogen is a molecule which stores energy, primarily in the liver and muscles. It is generally synthesised from carbohydrates via sugars such as fructose and glucose. Glycogen breaks down into glucose to provide energy as required.  The body can also generate glycogen via glyconeogenesis when carbohydrates are unavailable.

Hypoglycaemia: Hypoglycaemia refers to the amount of glucose in the blood being insufficient to supply the body and brain with the energy it needs to properly function.

Insulin: Insulin is a hormone produced in the pancreas which allows your cells to use the glucose in your bloodstream for energy. This includes helping your muscles grab and use the glucose in your blood. Low levels of insulin make it more difficult for your muscles to grab the glucose in your blood for use or storage.

Ketogenic diets: A ketogenic diet is one intended to put the body into a state of ‘ketosis’ by providing most of the bodies calories through fats and proteins rather than carbohydrates. Ketosis refers to the state in which most of the body’s energy is being derived from ketones in the blood. Ketones are produced by the liver when there is insufficient amounts of glucose available. While in ketosis the body will more readily and break down stored fat for energy than otherwise. Pushing the body into ketosis generally requires restricting carbohydrate intake.

Lasix: Lasix is a brand name of a diuretic typically prescribed to treat medical conditions which cause someone to retain too much water in a way that is dangerous or harmful to their health, such as edema, which is when excess fluid is trapped in your body tissues. It is banned for use in athletic competition by the World Anti-Doping Agency and most other regulating bodies.

Lutenizing Hormone: Lutenizing Hormone is a hormone produced by the pituitary gland which helps to encourage testosterone production in men.  Hypoglycaemia can lead to the body secreting less lutenizing hormone.

Macronutrients: Macronutrients are the things we consume, usually via eating/drinking, that provide us with most of our energy. They are protein, fat and carbohydrates.

Metabolic Equivalent: A method of expressing the energy cost of an action via oxygen consumption. One metabolic equivalent (MET) is equal to 3.5 ml O2 per kg body weight x min. This is how much oxygen your body consumes while sitting doing nothing, therefore one MET is the resting metabolic rate. An activity using two MET would require twice as much oxygen consumption as sitting doing nothing.