How much weight do UFC fighters cut?

5 to 8 percent of body mass in the final week. Almost none of it fat. The number is easy to find and it is the least useful part of the answer, because two fighters can remove the same 6 kilos and walk out in completely different condition.

The reported figure for Khamzat Chimaev's 2026 title camp was about 46 pounds across eight weeks, far outside that range. The arithmetic of that camp is on its own page.

The percentage is the part everyone quotes. It is also the part that tells you least.

What follows is the published research first, then what the same job looks like measured inside a world title camp: three cuts I ran myself, with camp figures alongside official weigh-in numbers anyone can check.

The methods themselves, in the order they are used, are in how UFC fighters cut weight.

What the research shows

The International Society of Sports Nutrition position stand on weight cutting in combat sports gives the clearest set of reference figures. They describe the upper end of what can be managed, not a target to chase.

A 2023 study of professional female UFC fighters tracked body mass at five separate points across fight week and found losses of 4.5% to 6.6% before the official weigh-in, with no meaningful difference between strawweight and featherweight. The percentage stays roughly constant across divisions. The absolute number does not.

Almost none of it is fat, which cannot be removed at that rate. It is gut content, water bound to glycogen, and body water.

What the early weigh-in changed

Before June 2016 UFC fighters weighed in during the afternoon, roughly 24 hours out. From UFC 199 the official weigh-in moved to a morning window, usually 9 to 11 a.m. the day before the event. The afternoon appearance most fans watch is ceremonial and records nothing.

The stated aim was safety: more hours to rehydrate before competing. Fighters got roughly six to 10 extra hours.

What happened next is the part worth understanding. An analysis of UFC weigh-ins across the 2 years either side of the change found the rate of fighters missing weight rose from 5.7% to 8.4%, and the average amount they missed by rose from 2.9 lb to 3.9 lb.

Boxing still weighs in during the afternoon the day before. So a boxer's cut is done on the tighter window: less time on the clock, the same physiology. Everything below was run under that constraint.

Three world title camps, with the numbers

I worked as the nutritionist in Oleksandr Usyk's camps at cruiserweight, where the limit is 200 lb, or 90.72 kg.

The weigh-in figures are public record. The camp figures are mine.

Read the Gassiev and Bellew rows again. Roughly 7.6 kg left the body in the final 24 hours. On a 97.5 kg athlete that is 7.8% of body mass, above what the position stand calls manageable at that point. I will come back to why that is not a recommendation.

What was different was not the amount

The amount was large. The method was not what most people picture.

No sauna. No sweat suit. No training in the final 24 hours. He did not run, did not spar, did not sit in heat. The last day was food calculation and water manipulation, nothing else. A fighter who trains himself down on the final day arrives at the scale already damaged, and the damage is still there the next night.

The 8 weeks came first. Through camp I held him at 98–99 kg deliberately. Not lower. A fighter who spends 8 weeks under-eating to stay light reaches fight week with nothing in the tank, and then the body will not give the water back easily.

That photograph is a champion arriving for fight week eating rice with turkey in the back of the car. It is what a fighter looks like when he has not been starved through camp, and it is the reason the last 24 hours are able to work at all.

That decision was not uncontested. His head coach, Anatoly Lomachenko, asked me to bring him down to 93.5 kg for camp. His reasoning was sound from where he stood: at 98 kg the fighter was heavy, and heavy meant he could not complete the full volume of work the coaching staff wanted.

Then I gave him the number. Usyk walks around at 102–103 kg in the off-season. You cannot hold a man that size at 93 kg for 8 weeks and expect anything to be left of him. He would make the weight and step through the ropes empty.

We kept him at 98–99. The scale reads the same either way. The fight does not.

Water loading at 6 litres, not 10. The controlled protocol uses roughly 100 ml per kilogram per day, which for a 98 kg athlete comes to close to 10 litres. I used 6 litres a day across the 7 days before the weigh-in, roughly 60 ml per kilogram, then closed the window entirely for the final 24 hours: no fluid and no food until the scale.

Sixty millilitres per kilogram was enough to trigger the diuresis and take off what was left. The heavy lifting was done by the food plan, not by the water. Making the weight has never been the hard part. Arriving at the scale with your own resources intact is the hard part.

The exception that shows the rule

On the morning of the Bellew weigh-in he woke at 9 a.m. half a kilo over. The plan allowed 200 g. We were going to walk it off, but he had to get a work visa stamped in his passport that day to be paid for the fight, and that took the morning. We got back from the police station an hour before the weigh-in and he was still 500 g heavy.

He put on a sweat suit, ran 80 metres up the hotel corridor and 80 metres back, shook his arms out, and lay under a blanket for 5 minutes. That was it. He weighed in at 198.4 lb.

Five minutes and half a kilo, at the end of a process that had already done the work. That is the difference between a suit used as a correction and a suit used as a strategy.

What it looked like on fight night

A cut that worked should be visible in the fight, not only on the scale.

Against Gassiev over 12 rounds, CompuBox recorded Usyk throwing 939 punches and landing 252. Gassiev threw 313 and landed 91. His jab alone accounted for 519 of those, an average of 43 per round against a cruiserweight average of 23.

The distribution matters more than the total.

Output in the second half was roughly half again what it was in the first, and the best round of the fight was the last one. That figure of 47 landed sits against a cruiserweight average of 15 per round.

A fighter damaged by his cut fades after round six. This is the opposite.

That is roughly 24 hours after stepping off the scale at 90.5 kg.

The other corner

Bellew came down to cruiserweight from heavyweight, where he had weighed 213½ lb against David Haye in 2017 and 210¼ lb in the rematch in May 2018. By September, with 11 weeks to the fight, the British press was describing him as being in the 220s.

At the pre-fight press conference I watched him drink a protein shake. That told me two things. He would make the weight, and he would pay for it.

A fighter held close to competition weight for weeks is not carrying spare capacity. The weight comes off because there is nothing else for the body to give, and it comes out of his own reserves rather than out of water. My read at that moment was that he would fade in the second half through the cut rather than through the punches. He was stopped in the eighth.

That is my reading of an opponent from the outside, not a claim about what his team did. But it is the reason I hold athletes high through camp.

The regain is the point

This is the part that gets missed.

The target after the Gassiev and Bellew weigh-ins was to bring him back to 97.5 kg, exactly where he had been the day before. Not "as much as possible". A number, decided in advance. When he hit it, the cut had worked. If he had not, the cut had failed, whatever the scale said the night before.

Some bouts now cap that regain contractually. What a rehydration clause is, and which bodies actually enforce one, is worth knowing before you sign.

That is not only my preference. Research on real competition has found that weight regain after the weigh-in, rather than weight loss before it, is what tracks with winning. And studies of repeat-effort performance have found deficits still present 24 hours after acute dehydration. The body does not reset because you ate a meal.

What that looked like in practice:

• Electrolytes first, targeting around 150% of the fluid lost. This is the base and it is not optional. The order it goes back in decides how much of it stays.
• Then a full-sugar cola and salted crisps. Not a supplement stack. Sodium, sugar and fluid in a form the athlete will actually finish.
• No food for the first hour to 90 minutes. The gut does not want it yet.
• Then a restaurant, and whatever he asked for. Nothing bought in advance, nothing prepared. For the first half of the day after the weigh-in he ate what he wanted.
• By the evening, back to structure. The free window closes and the food becomes deliberate again.
• Three to 4 meals between the weigh-in and bed, and three to four again on fight day, timed backwards from the first bell. Nothing fried, nothing heavy, nothing new.

Across 4 camps this never produced a difficult cut. That is not luck. The reason he could eat freely for half a day is that he had fasted for 24 hours, not starved for a week. A fighter depleted for a month cannot be handed a menu the night before a world title fight and be expected to absorb it. The strategy is what buys the freedom.

So how much is too much

I have just described a 7.8% loss in 24 hours, and the published guidance says 4.4%. I am not going to pretend those agree.

Three things separated that camp from a dangerous cut. If any one of them is missing, the number is not defensible.

• A 97 kg professional, not a 60 kg junior. The same percentage on a smaller athlete removes a much smaller absolute buffer.
• Daily supervision by someone physically present, measuring, and able to stop it.
• Eight weeks of deliberate feeding beforehand, so the body had something to give.

The short version

5 to 8 percent is the range. The number on its own predicts nothing. What predicts the fight is whether the athlete arrived at fight week full or empty, and whether the weight went back on to a figure someone decided in advance.

How much comes back overnight, measured on fight night across three UFC cards, is in how much weight UFC fighters gain after the weigh-in.

Common questions

How much weight do UFC fighters cut in 24 hours?

The final 24 hours typically removes 2 to 4 percent of body mass through acute water loss, on top of the glycogen and gut-content reductions made earlier in the week.

Do fighters lose fat during fight week?

Essentially none. Fight-week loss is water, glycogen and gut content. Fat loss happens across camp, over weeks.

Do fighters need a sauna to make weight?

No. The three cuts described here were made without sauna or sweat suits, using water manipulation and calculated food intake. Heat is a correction tool, not a method.

Why do UFC fighters weigh in so early?

The UFC moved official weigh-ins to a morning window before UFC 199 in June 2016, giving fighters roughly 30 hours or more to rehydrate before competition instead of around 24.

How fast do fighters put the weight back on?

Most regain a significant share within the recovery window, though research shows performance is not always fully restored within 24 hours of acute dehydration.