Between fights: 12 to 15 percent, and the number nobody knows

There is a published figure for what a fighter should weigh between camps. 12 to 15 percent above the division limit. In 10 years I have met a handful of fighters who had heard it.

Everybody plans the camp. Almost nobody plans the part before it, and the part before it decides how the camp goes.

This is the article I would give a fighter the week after his last fight, not 8 weeks before his next one.

The number

The ISSN position stand on combat sports, published in 2025, is explicit about it. During the off camp or general preparation phase, athletes should maintain a body mass 12% to 15% above the weight division requirement.

Used the other way round, that band also answers which division you belong in.

It is also what decides whether a short-notice call is an opportunity or an impossibility, which is worked out in short notice, and it is the figure a fighter returning from a long break should reach before signing anything: coming back after a layoff.

This is also the only phase in which a fighter can add mass, if the plan is to move up.

Why that is rarely necessary, and what it costs when it is, is in moving up a weight class.

See the arithmetic behind it once, because it makes the figure usable rather than arbitrary. A typical acute cut takes around 5% of body mass. A sane longitudinal descent removes roughly 0.5 to 1% a week across an 8-week camp.

Add those together and you land in the low teens.

The authors are honest that the range is not fully substantiated by research and rests partly on practical application.

But it exists, it is published, and it beats the alternative, which is no number at all.

They also note that larger reductions are common practice. Losing 13 to 15% of body mass over an 8-week camp has been associated with testosterone falling below clinical reference ranges and with a decrease in resting metabolic rate.

The overshoot

What actually happens after a fight, and it has been measured.

A case study of a professional male mixed martial artist tracked body mass in the 2 weeks after competition. He came in 4.2% above the baseline taken before his fight camp had even started.

Not back to where he began. Past it.

That is a ratchet. Each camp starts a little higher, each descent is a little harder, and the fighter concludes that he is getting older or softer when what actually happened is that nobody managed the weeks in between.

What the cycle costs

A 2024 narrative review examined the metabolic consequences of this pattern in combat athletes. Short term: reduced metabolic rate, altered insulin and leptin. During regain: insulin resistance. Over years, the authors raise the possibility of contribution to metabolic dysfunction, while being careful that definitive support is not yet there.

A 2025 case study followed an elite female muay thai athlete through a 5-week camp. Resting metabolic rate fell by 253 kcal a day.

Creatinine and urea rose, the lipid profile moved unfavourably, and maximum cycling power output dropped by 27%.

Twenty-seven percent of peak power, in an athlete preparing to fight.

Fat-free mass loss was limited to 0.6 kg, which tells you the protein side of that camp was handled well. Diet quality held up; the problem was the size of the job the camp was asked to do.

What the off phase is actually for

The position stand describes it plainly: advancing aerobic capacity, technical skill, developing strength and power, and maintaining an appropriate body mass.

Read the order. Body mass is last, and it is the word maintaining rather than losing. This is the only window in a fighter's year when he can build something, because he is the only time he is properly fed.

Everything you gain during camp, you gain despite a deficit. Everything you gain between camps, you gain with the physiology on your side.

Floors that should not be crossed

The position stand sets minimums for the descent itself, and they are worth knowing because they define what a sane camp looks like.

• Carbohydrate not below 3.0 to 4.0 g/kg
• Protein 1.2 to 2.0 g/kg, prioritised throughout to protect lean mass
• Fat not below 0.5 to 1.0 g/kg

If a camp requires going under those to reach the limit in time, the camp did not start from the right weight. That is the whole argument of this page in one sentence.

What I would do the week after a fight

Recover deliberately for a week or two. Eat, sleep, do very little. That is not indiscipline, it is the repayment of a real debt, and skipping it is why people never get back to baseline properly.

Then weigh yourself and write the number down. Not to react to it. To know it. Most fighters genuinely do not know what they weigh between camps, only what they weigh in fight week.

Set the target from the division, never from a feeling. 12 to 15 percent above the limit. If you are 25 percent above, you are in the wrong division rather than out of shape, and that is a strategic conversation rather than a diet one.

Hold it with food, not with cardio, and the one supplement worth reconsidering in this phase is creatine. Between camps is when you build engine and strength.

Using conditioning as a weight-control tool costs you the training adaptation you came for.

Check monthly, not daily. The scale between camps is a trend line. A daily reading in a fed athlete is noise, and watching it every morning is how a fighter starts thinking about food the way he thinks about it in fight week.

The sentence I would put above the door

The camp you are about to have was decided by the 8 weeks before it started.

Fighters believe camp is where the work happens, and in a training sense it is. But the size of the gap you have to close was set long before anyone signed a contract, and no amount of discipline inside camp fixes a starting weight that was wrong.

12 to 15 percent. It is a number, it is published, and holding it costs less than one hard cut.