The weight cut is a tax. Here is the rate.

Nobody puts the weight cut on the fight poster. It is the part of the sport that happens in a bathroom, wrapped in a bin bag, with a coach watching a scale and a phone counting the minutes to the weigh in. It is also the part where a fighter can lose the fight a day before it starts.

The research has been measuring it for a decade now, and the numbers are steady enough to plan around.

Everybody cuts

In 2019 James Connor and Brendan Egan surveyed thirty competitive MMA athletes from clubs around Dublin, amateur and professional. All but one of them lost weight to compete, 97 percent. The average loss was 7.9 percent of habitual body mass, with a spread of plus or minus 3.1, and the most common methods were water loading, fluid restriction and hot salt baths.¹ Across combat sports the reviews put the share of athletes who cut at 60 to 80 percent, with the highest rates in boxing and MMA, and they draw the line for rapid weight loss at five percent of body mass.⁴

The elite are no different in kind. A 2022 study of UFC athletes put the loss at about 6.7 percent of total body weight in the 72 hours before the weigh in.² Seventy two hours. Most of that is water, and most of the water is supposed to come back.

Irish MMA athletes, mean7.9%

UFC athletes, 72 h before weigh in6.7%

Threshold researchers call rapid weight loss5%

Connor and Egan 2019 (Irish MMA, mean of habitual mass) and the 2022 UFC weigh in study (72 hours before the weigh in).

The rebound is the fight

The most useful finding is not about the loss. It is about what happens after. A 2023 analysis of 1,400 MMA weigh ins found that faster weight regain between the scale and the cage predicted winning.³ Read carefully, that is not an argument for cutting more. It is an argument that the fighter who arrives on Saturday closest to the body that trained is the one who wins, and that the cut is a tax on that body. You pay it in the bathroom and you try to claim it back in twenty four hours.

A cut you plan is a tax at a known rate. A cut you improvise is a tax with a penalty.

The scale is not the opponent. The opponent is whatever the scale took from you and did not give back.

Plan the cut like the camp

We are not doctors and this is not medical advice. It is the shape of the cuts that go well, seen from the corner and from the research, written for the fighter and the coach who plan the camp together.

• Decide the weight class with a calendar, not a mirror. If the last five percent has to come from water every camp, the class is wrong or the diet is.
• Lose the fat in weeks, not the water in days. The research separates the two. The first is a diet, the second is a cut. A camp that only does the second is a camp that is late.
• Know your own rate. Weigh every morning of camp and write it down. After two camps you know how many kilos come off in a sauna hour, and you stop guessing at midnight.
• Water loading is a method, not a hobby. It appears in the studies because it works, and it works because it is timed. Timed by someone who has done it before, with a plan on paper.
• The refeed is training. Sodium, carbohydrate, fluid in stages, and sleep before the big plate. The rebound decides the fight, so rehearse it in camp at least once.
• Never cut alone. The bathroom is where fighters have died. A coach, a phone with signal and a stop line agreed before the day.

The story nobody films

The weight cut is also the most honest content a fighter will ever produce, because nobody can fake a bin bag at four in the morning. We ask the fighters we work with to let a camera in on the cut, on their terms, because the audience that follows a fighter through that day follows him to the ticket page. The cut is a tax. It can also be the chapter that pays.

Camp, cut and fight week, filmed and cut as one series: boxingfinesse.de/athletes.