Weight Cut Stack for Combat Sports: 6 Supplements, 3 Phases, and 5 Things to Drop Before Weigh-In

Key caveat. Creatine, high-sodium pre-workouts, OTC diuretics, and proprietary blends belong off the table for this entire window. The protocol below explains exactly why, with mechanisms not marketing.Stack-kit editorial

If you've never cut weight for a fight, here's the one-line version: in the last week you'll strip off water and food to make the scale, then put it all back fast before you compete — and the supplements that help you the rest of the year mostly hurt you during that week.

That's the part most people get wrong. They keep their usual stack running straight into weigh-in because it "worked all season," and it quietly fights the cut the whole way down. The seven days before weigh-in in combat sports — MMA, boxing, wrestling, judo, BJJ — are the most supplement-hostile training environment most athletes will ever face. Caloric restriction, fluid manipulation, and a recovery window squeezed down to nothing all run at the same time, and the wrong stack in that window actively costs you weight or performance. So we built this around the three phases as they actually happen in sequence — the cut itself, the rehydration scramble after you step off the scale, and fight day — with exact doses, timing, brands, and the studies behind each call.

Quick answer — the full protocol at a glance

Key caveat. Creatine, high-sodium pre-workouts, OTC diuretics, and proprietary blends belong off the table for this entire window. The protocol below explains exactly why, with mechanisms not marketing.

Hard safety boundary. This page is for adult competitors working with an experienced coach and, ideally, sports-medicine oversight. It is not for casual weight loss, youth athletes, pregnancy, eating-disorder history, same-day weigh-ins with a meaningful dehydration cut, kidney disease, heart disease, uncontrolled hypertension, diuretic use, or anyone on a physician-directed sodium/fluid restriction. Rapid weight cutting can cause heat illness, hyponatremia, kidney injury, arrhythmia, fainting, and worse. Stop the cut and seek medical help for confusion, fainting, chest pain, severe cramping, vomiting, inability to keep fluids down, dark urine, severe headache, or abnormal heart rhythm. Do not use OTC diuretics, sauna suits, laxatives, or stimulant thermogenic stacks to force the scale.

Phase A: The Cut (Day 7 Through Weigh-In)

Beta-Alanine — Maintain What You Already Built

Beginner read: this one isn't something you start during fight week — it's something you protect. If you've been taking it for weeks, keep going. If you haven't, this week is too late.

Mechanism

Beta-alanine works by slowly raising muscle carnosine — a buffer that mops up the acid your muscles dump out during hard, oxygen-starved efforts — and it builds up only across four to six weeks of daily dosing. That buffering is exactly what matters in rounds two through five of a match, where the accumulated acid load narrows the gap between "performing" and "surviving." None of this is acute. A single dose the morning of a fight does nothing.

Dose

3.2g/day, split into four 800mg doses taken with food throughout the day. Hold that dose straight through the cut. Here's the thing people miss: stopping during fight week saves you none of the water weight you're chasing and throws away carnosine that took six weeks to bank. If the calorie restriction makes the full dose hard to stomach — and paresthesia, that pins-and-needles tingle, hits harder on an empty, calorie-restricted gut — drop to 4 × 400mg/day. That's the maintenance floor, not a number to go below.

Brand

Momentous Beta-Alanine — NSF Certified for Sport, 3.2g per serving, approximately $38 per 30 servings. [Affiliate link →]

Study

Hobson et al. (2012) — systematic review and meta-analysis, 18 trials, N = 360 subjects; pooled effect size ES = 0.374 (95% CI 0.26–0.49) for exercise bouts between 60 and 240 seconds in duration. No statistically significant effect for efforts under 60 seconds. Amino Acids, 43(1):25–37.

When to skip it

Skip it outright and start a loading cycle the week after the event if you haven't already completed a minimum four-week loading phase before fight week — there's nothing to maintain yet. Skip it too if your competitive rounds typically end in under 60 seconds, where the buffering benefit doesn't show up, or if you genuinely can't manage paresthesia at your Phase A calorie intake even at the 400mg dose.

Sodium Depletion Taper — The Primary Water-Weight Lever

Beginner read: cut back on salt for a few days and your body sheds water with it. This is the single biggest water lever you have — and it's free, because the "supplement" here is mostly the stuff you stop taking.

Mechanism

Pull dietary sodium down in the three to four days before weigh-in and you trigger a 24–48 hour aldosterone lag — aldosterone being the hormone that tells your kidneys to hold onto sodium. As it drops, the kidneys excrete more sodium, and water follows it out at roughly 3.7ml per mmol excreted. This is the most evidence-supported lever for the water side of a fight-week cut. Strictly speaking it's a dietary manipulation, not a supplement — but it lives here because the most common Phase A supplement mistakes directly sabotage it. High-sodium BCAAs, pre-workouts, and electrolyte drinks taken during the depletion window work against the aldosterone lag and cost you water weight.

Dose + timing

Days 7–4: eat your normal dietary sodium (~2,000–3,000mg/day). Days 3 through weigh-in: drop under 500mg/day only if your coach and medical context support a fluid-manipulation cut. Through that window, every electrolyte-containing supplement comes out — Precision Hydration, high-sodium protein powders, flavored BCAAs, all of it. Everything resumes the moment you're off the scale, in Phase B.

Brand

Not applicable. The move is removing products you already own, not buying a new one. Phase A spend on this item is zero.

Study

Shirreffs et al. (1996) — N = 8 trained males; beverages with sodium concentrations above 20 mmol/L produced significantly greater 6-hour fluid retention versus low-sodium controls matched for volume (p < 0.05). The mechanism validates sodium depletion as a water-weight lever: obligate fluid follows sodium in both directions. Medicine & Science in Sports & Exercise, 28(10):1260–71.

When to skip it

If your cut is built entirely on caloric restriction with no fluid-manipulation component, talk to your coach before adding a sodium taper — it may be solving a problem you don't have. Skip it entirely for youth athletes, pregnancy, eating-disorder history, uncontrolled hypertension, renal impairment, cardiac conditions, documented hyponatremia history, diuretic use, or any medical sodium/fluid restriction unless a sports-medicine clinician is directly supervising it. This one isn't a judgment call.

Tart Cherry Extract — Inflammation Control Under Restriction

Beginner read: your last hard sessions of the cut beat your body up at the worst possible time. Tart cherry takes some of that edge off — but only if you start it days ahead, not the night before.

Mechanism

Montmorency tart cherry is loaded with anthocyanins — the same pigments that make it red — and they tamp down the COX-1 and COX-2 inflammatory pathways, lowering the post-exercise spikes in CRP, IL-6, and creatine kinase that track tissue damage. Your final training sessions of cut week happen under restriction and on shortened recovery, which is the highest cumulative tissue-damage rate in most fighters' whole training block. It needs three to five straight days of dosing before those inflammatory markers move in any meaningful way. A single pre-fight dose is not a strategy.

Dose + timing

480mg anthocyanin-standardized extract twice daily, or 30ml of concentrated juice standardized to equivalent anthocyanin content, twice daily. Start Day 7 of the cut and carry it through fight day — this is the one item that spans both Phase A and Phase B.

Brand

Thorne CherryFlex — NSF Certified for Sport (verify current product-level certification status at time of purchase; Thorne certification is per-product, not brand-wide), approximately $28 per 90 capsules. [Affiliate link →]

Study

Howatson et al. (2010) — N = 20 marathon runners; tart cherry juice at 2 × 30ml/day for five days pre-race through race day significantly reduced post-race muscle soreness, creatine kinase (p = 0.03), and inflammatory markers versus matched placebo. Scandinavian Journal of Medicine & Science in Sports, 20(6):843–852.

When to skip it

Skip it if you're on NSAIDs or antiplatelet medications — the anthocyanins may potentiate anticoagulant effects, so clear it with your prescribing physician first. Skip it if you have documented salicylate sensitivity. And skip it if your cut runs under five days, because the accumulation window never closes and you're paying for an effect you won't get.

The Protocol — Detailed

Phase B: Rehydration Window (Weigh-In Through 2 Hours Pre-Competition)

Precision Hydration PH1500 — Sodium-Driven Fluid Retention

Beginner read: after weigh-in, chugging plain water is a trap — most of it just runs straight through you. Salty water actually stays in. That's the whole game in this phase.

Mechanism

Post-weigh-in rehydration is not "drink as much water as you can." Plain water taken fast dilutes plasma sodium, slows gastric emptying — how quickly your stomach hands fluid off to the gut — through osmotic feedback, and prompts your kidneys to pee out a real chunk of what you just drank. Sodium-containing solutions hold plasma osmolality steady, keep the absorptive drive running across the intestinal wall, and pull more fluid into the plasma and interstitial compartments where you want it. PH1500 at 1,500mg sodium per liter (~65 mmol/L) is the highest-sodium commercially available NSF Certified for Sport oral rehydration product, and it's the right tool for a fighter walking into a compressed rehydration window after a serious sweat deficit.

Dose + timing

The instant you're off the scale: 750ml–1L of PH1500 solution inside the first 30 minutes. Then 500ml every 30–45 minutes for the next two to three hours. Your total fluid target is 150% of estimated sweat deficit — take pre-cut bodyweight minus weigh-in weight to get the deficit, then multiply by 1.5. Don't exceed 1L/hour later in the window once you start mixing in lower-sodium co-beverages; hyponatremia risk climbs when water volume is high and sodium co-load isn't keeping up. If your weigh-in-to-fight window is under three hours, scale total volume down proportionally and put the sodium front-load first.

Brand

Precision Hydration PH1500 — NSF Certified for Sport, 1,500mg sodium per 500ml serve, approximately $3 per serve. [Affiliate link →]

Study

Shirreffs et al. (1996) — cited above in Phase A; the mechanism runs bidirectionally. Higher sodium concentrations (above 20 mmol/L) retained significantly more fluid at six hours versus low-sodium controls at matched volume. PH1500 at ~65 mmol/L exceeds the validated threshold by a factor of three.

When to skip it

If your competition uses same-day weigh-ins with under 90 minutes between the scale and the first bell, a full rehydration cycle simply isn't completable — take a single 500ml dose and don't try to force aggressive fluid loading into a timeline that can't hold it. Same-day weigh-ins should also rule out any meaningful dehydration cut in the first place. And with hypertension or any physician-supervised sodium restriction, get medical clearance before high-sodium rehydration.

Maurten 320 — Glycogen Restoration at Certified Rates

Beginner read: the cut also drains your fuel tank. This refills it fast, in the same window you're rehydrating — and you start both at the same time, not one after the other.

Mechanism

Caloric restriction during the cut empties liver glycogen within 12–18 hours and grinds muscle glycogen down progressively as training continues. Liver glycogen is what keeps your blood sugar steady through a fight; muscle glycogen is what caps your high-intensity work in the later rounds. Refilling it means getting carbohydrate in alongside fluid in the post-weigh-in window, while glycogen synthase — the enzyme that builds glycogen back up — is running hot. The ceiling for glycogen synthesis is roughly 1.0–1.2g carbohydrate/kg/hour in the first two hours after depletion. Maurten 320's dual-transporter formula uses an engineered glucose:fructose ratio to saturate two independent intestinal transporters at once, which lets it approach that ceiling while sitting easier in the gut than an equivalent glucose-only load.

Dose + timing

Start the carbohydrate at the same moment as your Phase B fluid — don't wait to "let the fluid settle first." Target 1.0–1.2g/kg/hour across the first two hours post-weigh-in. For an 80kg fighter that's about 80–96g carbohydrate per hour, and one serving of Maurten 320 (80g carbohydrate in 500ml) per hour hits it. Run it on the same schedule as your PH1500 rather than as a separate drink event.

Brand

Maurten 320 — dual-transporter hydrogel, NSF Certified for Sport, 80g carbohydrate per serve, approximately $4.50 per serve. [Affiliate link →]

Study

Ivy et al. (2002) — N = 10 trained cyclists; carbohydrate supplementation administered immediately post-exercise increased muscle glycogen synthesis rate by 38% at four hours versus delayed carbohydrate intake (45 minutes post-exercise). The timing window is the load-bearing finding: synthetic rate is highest in the first 30–60 minutes post-depletion and declines thereafter. International Journal of Sport Nutrition and Exercise Metabolism, 12(4):383–402.

When to skip it

If your cut was mild — under 1.5% bodyweight reduction with no caloric restriction — you may not be meaningfully glycogen-depleted, so there's little to restore. And a big carbohydrate bolus on a sensitized pre-competition gut carries real GI risk: start at 0.5g/kg/hour and scale up with tolerance rather than leading with the full load.

Phase C: Fight Day (60–90 Minutes Pre-Competition)

Caffeine — Reaction Time, Pain Tolerance, Neural Drive

Beginner read: caffeine sharpens you up on fight day — but it pays off far more if you've laid off it for the prior week. Daily coffee drinkers get a fraction of the effect.

Mechanism

Caffeine blocks adenosine receptors centrally and peripherally — adenosine being the molecule that builds up and tells your brain it's tired — which pushes back perceived fatigue and turns up neural drive to working muscles. In combat sports the acute, evidence-supported effects are specific: faster simple and choice reaction time, a higher pain tolerance threshold, better sustained attention under fatigue, and a modest bump in peak power output. The effect is biggest in athletes who've tapered or cut habitual caffeine for five to seven days before the event; habitual daily drinkers with no washout see a blunted response on the same dose.

Dose + timing

3mg/kg bodyweight, taken 60 minutes before competition onset. For an 85kg fighter that's 255mg — two Klean Athlete tablets at 200mg total, plus 55mg from a small black coffee, or just round down to 200mg if anxiety is a known pre-competition response for you. Do not exceed 6mg/kg; past that the performance returns flatten out while tachycardia, anxiety, and GI disruption climb. Take it with 200–300ml water, and skip the completely empty stomach if you're GI-sensitive.

Brand

Klean Athlete Caffeine Tablets — NSF Certified for Sport, 200mg per tablet, no proprietary blend, approximately $18 per 60 tablets. [Affiliate link →]

Studies

Grgic et al. (2020) — meta-analysis, 21 studies, N = 283; caffeine at 3–6mg/kg produced significant improvement in maximal muscular strength (ES = 0.20, 95% CI 0.11–0.28) and muscular endurance (ES = 0.35, 95% CI 0.20–0.51). British Journal of Sports Medicine, 54(11):681–688. For reaction time: Duvnjak-Zaknich et al. (2011) — N = 12 team-sport athletes; 6mg/kg caffeine improved reactive agility time by 3.8% versus placebo (p < 0.05). Medicine & Science in Sports & Exercise, 43(8):1523–30.

When to skip it

If you have a documented anxiety disorder or pre-competition panic response, caffeine at 3–6mg/kg will push your pre-fight anxiety higher and most likely drag performance down with it. If you have a cardiac arrhythmia or take beta-blockers, caffeine is contraindicated — talk to your cardiologist, full stop. And if your event runs a youth combat format with caffeine testing limits — rare, but real in some scholastic boxing and youth wrestling associations — confirm with your governing body first.

What to Cut and Why

Five things show up in fight-week stacks again and again, and every one of them costs athletes performance. Here's why each comes out.

Creatine — pause Day 7 through weigh-in. The thing that makes creatine useful (phosphocreatine resynthesis) and the thing that makes it a liability in a cut (intramuscular water retention, roughly 1–2kg in loaded athletes) are the same mechanism — you can't keep one without the other. Every gram held in muscle drags water along with it. If you're running a water cut, creatine is pulling the opposite direction from Day 7 to the scale. Bring it back the moment you're off the scale as part of Phase B, if you carry a loading dose.

OTC diuretics and thermogenic "weight loss" stacks — remove entirely. OTC diuretics — hydrochlorothiazide analogs, herbal "water pills" built on dandelion or uva ursi — flush electrolytes in a way you can't control, which then wrecks your Phase B rehydration response. Thermogenic stacks, usually caffeine + synephrine + yohimbine blends, pile uncontrolled diuretic and cardiovascular load onto a body whose training stress is already near peak. The sodium and electrolyte disruption from both conflicts head-on with the Phase A aldosterone-lag mechanism.

High-sodium pre-workouts — remove during Days 3 through weigh-in. Most pre-workout blends carry 200–500mg of sodium per serving, on top of undisclosed electrolyte content riding in through the flavoring systems. Inside the Phase A sodium depletion window (Days 3 to weigh-in), a single serving can put back enough sodium to blunt the aldosterone-lag effect for 6–12 hours. If you need a lift for cut-week training, borrow the Phase C caffeine dosing on training days instead.

BCAA powders — remove entirely for this window. No evidence supports BCAA supplementation as a meaningful performance or muscle-sparing intervention in athletes already eating adequate dietary protein. The flavored, electrolyte-fortified versions add sodium and often hide behind proprietary blends. In a Phase A sodium depletion window, that added sodium directly antagonizes the cut. The benefit-to-interference ratio doesn't clear.

Proprietary "combat sports" blends — remove and do not reintroduce. Products sold straight at combat athletes under proprietary-blend labeling — undisclosed per-ingredient doses — hand you two problems at once: you can't verify the dose, and you can't clear them for WADA or USADA compliance without NSF Certified for Sport or Informed Sport independent testing. One contamination failure ends a career. This protocol uses only NSF Certified for Sport products.

FAQ

Does the weigh-in-to-fight window change the protocol?

Yes, significantly. A 24-hour window lets you run Phase B in full — 150% deficit replacement across 3–4 hours of rehydration, plus glycogen restoration. A same-day weigh-in with under 3 hours between scale and first bell compresses Phase B down to a single 500ml PH1500 dose and modest carbohydrate at a GI-tolerable rate. Don't try to cram 2L of fluid and 160g of carbohydrate into a 90-minute window before you compete — GI distress is the near-certain result.

Should I add glycerol to the Phase A or Phase B stack?

Glycerol (as GlycoFuse or similar) has evidence for hyperhydration — boosting total body water retention — but its NSF Certified for Sport status is inconsistent across products, and some governing bodies prohibit it outright at high doses. If you're a tested athlete, confirm your governing body's position before using it. If you're untested, the Phase B PH1500 + volume protocol gets you the rehydration outcome you're after with cleaner certification status.

What about magnesium during the cut?

Magnesium depletion speeds up under sweat stress and caloric restriction. If you're running a cut longer than 7 days, or you've historically cramped in the later rounds, magnesium glycinate at 300–400mg nightly is a reasonable Phase A addition. Magnesium oxide has poor bioavailability — how much actually makes it into your system — and it's the form you'll find in most low-cost products, so specify glycinate. It didn't make the primary protocol because the evidence base is thinner than for the six named items, and cramping in combat sports is usually multifactorial anyway.

Can I run this protocol if I am not a tested athlete?

It applies either way. The NSF Certified for Sport requirement is there because unverified supplements carry contamination risk that can surface on a drug test — but that same contamination risk can hit your health and your performance regardless of whether anyone's testing you. Third-party testing isn't an administrative box to tick; it's quality verification. Tested or not, buy certified.

Does caffeine interfere with the Phase B rehydration?

Caffeine at 3mg/kg has a mild diuretic effect, but at exercise-habituated doses it's modest and doesn't offset the rehydration benefit inside the Phase B window. The concern matters more in Phase A: caffeine used as a stimulant during cut-week training doesn't meaningfully impair the sodium depletion mechanism. And Phase C timing — 60 minutes pre-competition — lands after the Phase B rehydration window has already closed, so the two never collide.

Affiliate Disclosure

Stack-kit earns affiliate commission when readers purchase through links on this page. Brand selection is not influenced by affiliate fee structure. Every brand named in this protocol was selected on NSF Certified for Sport certification status, dose transparency, and third-party testing record. If a better-certified equivalent exists at time of purchase, that product is the right choice. Affiliate relationships do not change that recommendation.