Weight Cutting for Beginners: 6 Mistakes to Avoid

Contents

To cut weight properly, lose most of it slowly over your camp, about 0.5–1 kg per week (ISSN, 2025), and keep the final water cut small, around the 2–3% of body weight you’d lose in normal training (Burke et al., 2021). Then refill properly after the weigh-in. Almost every beginner problem comes from breaking one of those three rules.

Your first cut is nerve-racking, and that’s where most mistakes happen. This guide is the practical how-to. If you want the background first, what cutting is and why fighters do it, read what is weight cutting.

What does a weight cut look like?

A good cut has phases, and each one removes a different kind of weight. Chronic loss (fat) happens over weeks; acute loss (water, glycogen, gut contents) happens in the last days before the weigh-in (Reale et al., 2017).

Phase	When	What you do	What you lose
Off-camp	Between fights	Stay roughly 12–15% above your division limit (ISSN)	—
Camp	Typically 8–10 weeks (ISSN)	Gentle calorie deficit, full training	Fat, about 0.5–1 kg/week
Fight week	Final days	Lower carbs and fibre, plan sodium and fluids	Glycogen water, gut contents
Final 24 hours	Before weigh-in	Small, supervised water cut	Water
After weigh-in	Until the fight	Fluids, salt, carbs	You regain the acute part

Mistake 1: You pick too low a weight class

The most expensive mistake of all. Aim for a class that needs a brutal cut and you spend the whole camp exhausted, and the final days in a sauna. The ISSN suggests staying about 12–15% above your division limit between camps (ISSN, 2025). If you’re far above that, the class is probably too low.

For your first fight, choose a class close to your normal, well-fed training weight. Our combat sports weight classes chart and how much weight you can cut guide help you check.

Mistake 2: You start too late

Water comes off fast, fat doesn’t. At 0.5–1 kg a week, you need weeks of lead time for anything beyond a small cut. The average fight camp runs 8–10 weeks (ISSN, 2025); start the gentle diet at the start of camp, not two weeks out.

Start late and you’re forced into the aggressive, acute methods for the bulk of the weight. That’s exactly where the risk lives.

Mistake 3: You cut calories too hard

A crash diet eats your muscle and your training. The ISSN sets floors that daily intake shouldn’t drop below during camp (ISSN, 2025):

Nutrient	Don’t go below (per kg body weight per day)
Carbohydrate	3.0–4.0 g
Protein	1.2–2.0 g
Fat	0.5–1.0 g

The ACSM links long-term low energy availability in weight-category athletes to problems with metabolism, hormones and, in younger athletes, growth (Burke et al., 2021). Read fight camp calories and macros to set your numbers.

Mistake 4: You lean on the sauna and sweat suits

Sweating is the riskiest way to lose water, and it’s far too common. In a survey of 637 combat athletes, MMA fighters reported the highest use of the sauna (76%) and water loading (67%), and 63% trained in rubber or plastic suits (Barley et al., 2018).

Passive sweating reduces plasma volume and raises the risk of overheating (Burke et al., 2021). If you use the sauna at all, keep it for the last small adjustment, never alone. See sauna weight cut for the safe limits.

Mistake 5: You forget the refuel

The weigh-in isn’t the finish line; the fight is. The ACSM recommends drinking about 150% of the fluid you lost and replacing sodium with it, which helps your body hold on to the fluid and limits urine losses (Burke et al., 2021). The ISSN recommends oral rehydration solutions at 1–1.5 litres per hour straight after the weigh-in, followed by fast-acting carbohydrate (ISSN, 2025).

Write the plan down before fight week. Our guide on how to rehydrate after the weigh-in gives you a timeline.

Mistake 6: You experiment in fight week

Fight week is not the time to try anything for the first time. Not water loading, not a new supplement, not a new meal plan. The ACSM still describes water loading as experimental, with a small risk of low blood sodium (Burke et al., 2021).

Acute weight loss also affects your head. Studies consistently find lower vigour and more anxiety, anger, fatigue, depression and confusion during rapid weight loss (Burke et al., 2021). Do a dress rehearsal in a normal training block so you know how your body responds when it matters.

How much should you cut for your first fight?

Less than the maximum, and mostly from camp. The numbers in the position stands are upper limits for experienced athletes, not targets for a debut.

Part of the cut	Upper limit in the guidelines	A sensible first-fight approach
Camp (fat)	0.5–1 kg per week (ISSN)	The lower end, so training stays sharp
Glycogen and fibre	About 1–2% of body mass each (ISSN)	Only if you’ve rehearsed it in a training week
Water	2–3% likely has few downsides; above 3% may cause real harm (Burke et al.)	As little as possible; ideally none with a same-day weigh-in

A simple test: if you’re more than a small water cut away from the limit at the start of fight week, move up a class for this fight. There will be other fights.

Track it the boring way. Weigh yourself every morning after the toilet and before food and drink, and follow the weekly trend rather than single days. If the trend is falling faster than about 1 kg a week, eat a little more.

Is it good to cut weight?

A small, planned cut is manageable; a big one is a gamble. The ACSM states that rapid weight loss causes some direct loss of performance, which can be at least partly offset if there’s enough time to recover after the weigh-in (Burke et al., 2021). Some researchers go further and argue that rapid weight loss should be banned from combat sports altogether, on health and fair-play grounds (Artioli et al., 2016).

For a beginner, the most useful mindset is: the less you need to cut, the better.

Methods you should never use

These appear in weight-cutting culture, but the evidence is clear that they don’t belong in your plan:

• Diuretics: banned in most sports and can cause electrolyte imbalance and cramps (Burke et al., 2021).
• Laxatives and enemas: banned in some sports, cause fluid loss and electrolyte imbalances (Burke et al., 2021).
• Fasting, diet pills, vomiting: explicitly not endorsed by the ISSN (ISSN, 2025).
• IV drips after the weigh-in: no better than drinking, and banned by sport governing bodies (Burke et al., 2021).

The short version

1. Pick a class close to your walking-around weight.
2. Start at the beginning of camp, 8–10 weeks out.
3. Lose about 0.5–1 kg a week and respect the macro floors.
4. Keep the sauna for a last small adjustment, if at all.
5. Plan the refill before fight week.
6. Test everything before fight week, never during it.

Do that and you’re ahead of most fighters on their first cut.

MyFightPrep helps you plan your first cut step by step, with weight, nutrition, hydration and training in one place — free.

Important

This guide is general information, not medical advice. If you’re new to the sport, do your first cut with your coach, and cut less than you think you can. If you’re under 18, don’t cut water weight at all: compete at or near your natural weight and involve your parents, coach and a doctor. If you feel dizzy, confused, unusually weak or unwell along the way, stop and seek help.

Frequently asked questions

How do you properly cut weight?

Lose most of the weight slowly during camp, about 0.5–1 kg per week according to the ISSN, then use lower carbs, lower fibre and a small, supervised water cut in the final days. Keep the water part to roughly 2–3% of body weight, and have a rehydration plan ready for after the weigh-in.

Is it good to cut weight?

A small, planned cut is common and manageable for healthy adults with a day-before weigh-in. Large, rapid cuts carry real health risks and can hurt performance, and some researchers argue rapid weight loss should be banned outright. For your first fight, the best cut is a small one.

What does a weight cut look like?

Typically an 8–10-week camp with a gentle calorie deficit, a fight week where carbs, fibre and sodium are reduced, a short water cut in the last 24 hours, and then a structured refill of fluids, salt and carbohydrates after the weigh-in. Each phase takes off a different kind of weight.

Sources

This guide is based on the works below. Numbers in the text refer to them.

1. Ricci AA, Evans C, Stull C, et al. (2025). International society of sports nutrition position stand: nutrition and weight cut strategies for mixed martial arts and other combat sports
2. Burke LM, Slater GJ, Matthews JJ, Langan-Evans C, Horswill CA (2021). ACSM Expert Consensus Statement on Weight Loss in Weight-Category Sports
3. Barley OR, Chapman DW, Abbiss CR (2018). Weight Loss Strategies in Combat Sports and Concerning Habits in Mixed Martial Arts
4. Reale R, Slater G, Burke LM (2017). Acute-Weight-Loss Strategies for Combat Sports and Applications to Olympic Success
5. Artioli GG, Saunders B, Iglesias RT, Franchini E (2016). It is Time to Ban Rapid Weight Loss from Combat Sports