The bodybuilding aesthetician

As someone who has spent years studying Exercise and Nutrition, and having done my MSc research project on weight cutting in combat sports, and completing the UFC Level 3 Specialist Sports Nutrition course, this is an area I’ve spent a lot of time on. I also love Muay Thai, and performance nutrition has always been a huge interest of mine, so this is something I care about both from a research and real-world perspective.

Weight cutting is part of the sport. That’s just the reality of it. But how you approach it can make a huge difference to how you feel, how you perform, and how repeatable it is across a season.

What Female Fighters Actually Do

Weight cutting is extremely common across combat sports, with around 80–90% of female fighters doing it, often multiple times per year. The most common methods you’ll see, both in research and in real life, are dieting during camp, increasing training volume, using saunas or hot baths, and manipulating fluids in the final days. Professional fighters tend to push things further than amateurs.

At higher levels, female fighters typically lose around 4.5–6.6% of their body mass in the final 72 hours before weigh-in. That is fairly consistent across weight classes. Where problems start to show up is when cuts go beyond about 5% in the last 24 hours, which is where you tend to see more fatigue, poorer performance, and higher injury risk.

How Weight Cutting Is Usually Structured

Most cuts follow a similar pattern, whether they are planned well or not. During the fight camp phase, the majority of the work should be done through a small calorie deficit, structured nutrition, and enough protein to preserve muscle and training quality. In the final 7–14 days, food gets a bit more controlled, training remains high, and some fighters start adjusting fluids. This is also where fatigue can creep in if things are not planned properly.

In the final 24–72 hours, acute strategies come into play. When done correctly, this is not about starving yourself, it is about shifting body content. Common strategies include water loading then pulling it back, reducing sodium, dropping carbs and fibre, and using sauna or hot baths to sweat. These can work well when controlled and not overdone.

Extreme methods such as laxatives, diuretics, vomiting, or diet pills still happen, especially at higher levels, but they increase risk without real performance benefit. These are methods to avoid from a coaching and evidence perspective.

A More Structured, Evidence-Based Approach

The goal is not to avoid weight cutting completely, it is to make it more controlled and predictable. Research supports keeping total loss in the final week to around 5% or less, avoiding going over that in the last 24 hours, and doing most of the work over 8–12 weeks during camp.

From a nutrition side, aim for protein around 1.2–2.0 g/kg to hold onto muscle, carbohydrates around 3–4 g/kg to keep training quality high, and fats at 0.5–1 g/kg to support overall function. Nothing extreme, just structured.

Using Carbohydrate and Fibre Reduction Properly

This is one of the most useful tools in fight week when done right. Dropping carbohydrates reduces glycogen stores, and because glycogen holds water, body weight comes down without relying on dehydration. Reducing fibre lowers gut content. A low-residue approach in the final few days can make a real difference, accounting for around 1–2% of body weight. It is practical and generally well-tolerated short-term.

Water Retention and Female Athletes

Water retention in women is shaped by both menstrual hormones and deliberate fluid manipulation for weight cutting. Average shifts across the cycle are modest, but for some individuals, they can be meaningful, especially when combined with acute cuts.

Estrogen and progesterone influence vasopressin and aldosterone, but for most women, overall fluid retention, plasma volume, and sweat losses change very little across the cycle. Some women see small increases in body weight of approximately 0.3–0.5 kg and extracellular fluid around menstruation or the luteal phase. MRI studies show calf muscle edema in some women during the menstrual phase, which can reduce agility if edema is noticeable.

During the late follicular phase, heat dissipation may be slightly improved, with no consistent extra edema. In the mid to late luteal phase, fluid retention increases slightly and may shift to extracellular space, leaving some women feeling “puffy” with a slight weight increase. During menstruation, small body weight increases occur in some women along with localized edema, which can slightly reduce agility.

Rapid cuts of 5–6% body mass in a few days rely almost entirely on body water loss, mainly extracellular water and plasma volume. This hypohydration can impair repeat-effort performance and heart-rate recovery if not carefully planned. Position stands recommend controlled acute water loss of 2–4% in 24 hours with structured rehydration and sodium replacement after weigh-in. Women should be cautious with water loading plus sodium restriction around the luteal phase, as higher hormone levels and naturally higher total body water may increase hyponatremia risk.

Practical tips include expecting 0.3–0.7 kg “hormonal water” swings during menstruation or luteal phase. For tight weight cuts, this can be the difference between making weight or not, so track your cycle and daily weight trends. When using water loading or sauna, avoid overdrinking with low sodium, particularly in the luteal phase, and prioritize structured rehydration after weigh-in with oral solutions containing sodium at 125–150% of fluid lost.

Menstrual Cycle, Hormones, and Weight Cutting

The menstrual cycle itself has small and inconsistent effects on objective performance, but symptoms and perceived effort can vary noticeably. Many women feel worse during early follicular (menstrual) and late luteal phases. The bigger risk comes from aggressive or repeated weight cutting combined with low energy availability. This can lead to menstrual disruption, suppressed ovarian hormones, changes in stress hormones like cortisol, and reduced recovery, bone health, and overall performance. Tracking your cycle, symptoms, and weight-cut responses can help guide safer, more effective planning.

Practical Takeaways

The most effective approach is usually the least extreme:

• Do most of the work during camp
• Use carbohydrate and fibre reduction strategically in fight week
• Keep acute cuts within a manageable range
• Avoid high-risk methods like diuretics and laxatives
• Take recovery seriously after weigh-in
• Track your cycle, symptoms, and water retention to understand what feels best for you

Take-Home Message

Weight cutting is not going anywhere in combat sports, but the way it is done makes all the difference.

A structured approach built around gradual fat loss, with smart use of fight-week strategies like carbohydrate and fibre reduction, careful acute water manipulation, and evidence-based rehydration, is the safest way to make weight while maintaining performance.

For female fighters, understanding your cycle, tracking symptoms, and avoiding aggressive or repeated cuts is key. The goal is not just to make weight once, it is to do it safely, effectively, and consistently every time you step into the ring.

Disclaimer: This information is for educational purposes only. Consult a qualified professional before making changes to your weight, nutrition, or training. Safety should always come first.