Kayla Harrison's weight cut

Kayla Harrison won two Olympic titles at 78 kg, about 172 pounds, and fought most of her professional career at 155. Since 2024 she has made 135.

The arithmetic, from judo to 135

Two rows in that table matter more than the headline number. On her own figures, 155 was barely a cut at all: she walked around only 5 to 10 pounds above it. And the last row asked for something the others did not. Non-title bouts allow 1 pound over the limit and title bouts allow none, so the title fight asked for that final pound too.

From the walk-around weight to 135 is 25 to 30 pounds. For scale, the largest survey of MMA athletes found professional men losing 5.9 percent of body weight in the final week before a weigh-in. A loss of 15 to 18 percent does not happen in a week, and in her case it did not.

Where the weight actually came from

Before the title fight, the descent she described started 15 weeks out. She ate only what her chef prepared, allowing herself a spoonful of peanut butter when a craving won, which she put at 3 times across the camp. From 14 weeks out she added cardio every day: a 6-mile walk, 2 hours on a bike or about 90 minutes of swimming, and 8 miles on Sundays. All of that sat on top of 2 training sessions a day.

That is the chronic phase, and a cut this size has to come mostly from there. What such a camp risks is well studied in general terms. The longer and harder the deficit, the more muscle tends to go with the fat, and the easier it is to run too little energy for the training being done. In professional MMA fighters followed by researchers, the slowest rates of loss preserved fat-free mass best. How the stages of a cut fit together.

My reading, from the outside: a 15-week descent with that much added cardio is how a careful team spreads a large loss across time. The division still sets the size of the loss.

The last pounds, and the night after

Her fight-week numbers are not public. Two data points are. She weighed 136 for her debut at UFC 300 in April 2024. On The MMA Hour afterwards she said she was 154 the next morning, and about 160 on the arena scale that night in clothes and shoes. The morning figure alone is 18 pounds, about 13 percent of her weigh-in weight, back in roughly a day.

For comparison, a UK study that followed 7 MMA fighters through a competition week recorded an average regain of 11.7 percent in 32 hours. A regain the size of hers means a large share of the last pounds came off as water, glycogen and gut content, because fat and muscle do not come back in a day.

Before UFC 307 in October 2024 she said she had gone to hospital the week before, urinating blood. She did not say what caused it, and the public record does not say either. She made 136 and won a unanimous decision over Ketlen Vieira, then said it had not been her best night, that she wanted time off because of the cut, and that she is "not built to weigh 135 pounds."

For the title fight in June 2025 she had to make 135 exactly, her first time at the championship limit, and she submitted Julianna Peña in the second round to win the belt.

What the results say, and what they do not

At this weight she is unbeaten in the UFC. A second-round submission of Holly Holm, a decision over Vieira, a second-round submission of Peña. On results alone, the cut has not cost her a fight.

Results are a blunt measure. The costs she has described sit in the camp and the week before: the hospital visit, the time off she asked for afterwards, and her own verdict that the process is unhealthy. Her UFC fights have come 6 and 8 months apart.

A title defense against Amanda Nunes was set for January 2026 and postponed when she had neck surgery, which nothing public connects to the weight. Her manager has said she will fight again toward the end of 2026. Bantamweight is the heaviest women's division the UFC runs, so as things stand the next fight asks for 135 again.

The part worth copying

Before she signed with the UFC, she ran a trial cut to 135 and simulated a fight at that weight. That is the one piece of her process every fighter considering a drop should copy: find out what a division costs before it is written into a contract.

The rest, the 15 weeks and the extra cardio, is what a large gap demands once the decision is made. Choosing the division sets the size of every cut that follows, and the calculator shows what a given gap means for your own weight and weigh-in format.

Common questions

How much weight does Kayla Harrison cut?

By her own figures, from a walk-around weight of 160 to 165 pounds in her PFL years to 135 or 136 on the scale, which is 25 to 30 pounds. Her fight-week numbers are not public.

What did Kayla Harrison weigh in judo?

She won Olympic gold in 2012 and 2016 in the 78 kg category, about 172 pounds.

Why does Kayla Harrison fight at 135 pounds?

Bantamweight is the heaviest women's division the UFC runs. She fought most of her career at 155 in the PFL, and the UFC has never promoted a women's 155-pound division.

Was Kayla Harrison hospitalized during a weight cut?

She said she went to hospital the week before UFC 307 in October 2024, urinating blood. She did not say what caused it. She then made 136 pounds and won by unanimous decision.