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OSMØ®
ANTI-CRAMP FORMULA

ANTI-CRAMP HYDRATION STICK

4.8 Rating 87 reviews on Trustpilot
Stomach friendly
Easy to mix
Tested by athletes
Not too sweet
No aftertaste

Built for the long sessions where water alone isn't enough. Each stick: 593 mg sodium, 402 mg potassium, 81 mg magnesium — designed around what heavy sweaters actually lose. No sugar. No sucralose. No fillers.

Stops cramping
593 mg of sodium per serving. Designed for heavy sweaters.
Olympic designed
Built with Olympic Champion Tom Digby and sports scientists, using real athlete sweat rate analysis.
Informed Sport certified
Tested for banned substances. Trusted by tested athletes.
Select Quantity
10 sticks per box
4.8 ★ from 87 reviews · 60-day money back
View full details

SOUND FAMILIAR?

White salt rings on your kit

Cramping during long sessions

Headaches after hot training

Hydration tabs that taste sweet but don't actually do anything

You're a heavy sweater. Kaiju is built for you.

Take the 60 second sweat test →

Why most cramps come from sodium loss

At a steady pace in moderate heat, you can lose up to ~1,200 mg of sodium per hour. Most sports drinks don't come close to replacing that. Kaiju does.

593mg

Sodium per serving

≈10×

More than a typical sports drink

0g

Sugar · sucralose · fillers

HOW KAIJU COMPARES TO OTHER ANTI-CRAMP ELECTROLYTES

Others
Kaiju
Sodium (Na)
Low dose
≈10× higher
Potassium (K)
Low dose
≈3× higher
Magnesium (Mg)
Missing
Included
Sugar
Dextrose
None
Sweeteners
Sucralose
None
Goal
Flavour
Performance

BUILT ON WHAT YOUR CRAMPING MUSCLES ACTUALLY LOSE

  • Elite level sodium

    593mg

    Elite level sodium

    Replenishes what you lose through sweat to maintain optimal hydration.

  • Potassium for muscle balance

    402mg

    Potassium for muscle balance

    Supports muscle contraction, nerve signalling, and steady energy output.

  • Magnesium for recovery and focus

    81mg

    Magnesium for recovery and focus

    Highly absorbable bisglycinate form, gentler on the gut than common alternatives.

A team that designs your hydration around your physiology.

Olympic Champion. Olympic medalist sports scientist. Performance nutritionist. They built the sweat test that tells you exactly how much sodium you actually lose per hour.

Tom Digby

Olympic champion

Co-founder of Kaiju. World class rower. Brings firsthand insight into endurance, recovery, and sustained performance.

Hélène Defrance

Sport scientist

Olympic medalist. Bridges research and practice.

Gareth Nicholas

Performance nutritionist

Renowned sports nutritionist. Shapes Kaiju's formulations with evidence based expertise.

Take the 60 second sweat test

WHAT HEAVY SWEATERS SAY

4.8 ★ from 87 reviews on Trustpilot

No more cramps
★★★★★

"First long ride this year without cramping. Cannot recommend enough."

Marc D.

Endurance cyclist · Girona

No more cramps
★★★★★

"First long ride this year without cramping. Cannot recommend enough."

Marc D.

Endurance cyclist · Girona

No more cramps
★★★★★

"First long ride this year without cramping. Cannot recommend enough."

Marc D.

Endurance cyclist · Girona

No more cramps
★★★★★

"First long ride this year without cramping. Cannot recommend enough."

Marc D.

Endurance cyclist · Girona

No more cramps
★★★★★

"First long ride this year without cramping. Cannot recommend enough."

Marc D.

Endurance cyclist · Girona

How to use

STEP 1

Take the sweat test

Find your sodium loss profile in 60 seconds.

STEP 2

Mix with 500 ml water

Pour one stick into your bottle.

STEP 3

Shake until dissolved

Shake for 10 seconds until fully mixed.

STEP 4

Sip through long sessions

Drink before, during, or after your session to hydrate and recover.

WHAT KAIJU DOES FOR YOU?

STOPS YOU BONKING

Sustained sodium where standard tabs run out. Built for heavy sweaters.

NO MORE CRAMPS

Replaces the salt your body actually loses during long sessions.

NO HEADACHES AFTER HOT SESSIONS

Magnesium bisglycinate, not malic acid filler. Gentle on the gut at high heart rates.

BOUNCE BACK NEXT MORNING

Better hydration recovery between sessions, so weekday training holds up.

FAQ

Why do I cramp so much when I sweat heavily?

Most exercise cramps are sodium-driven. Average athletes lose 800–1,000 mg/L of sodium in sweat; "salty sweaters" can lose well over 2,300 mg/L. When you don't replace it fast enough, the cramps come. Kaiju puts 593 mg back per stick.

Will Kaiju actually stop my cramps?

If your cramps are sodium-driven (most are), yes — most heavy sweaters using Kaiju report no more cramping. Each stick delivers 593 mg of sodium, about 10× a typical sports drink, plus potassium and magnesium. Take the 60-second sweat test to see how many sticks you need per hour.

How fast does Kaiju work on cramps?

Prevention is faster than treatment. Sip Kaiju steadily through long sessions and you front-load the sodium your muscles need. Mid-cramp, one stick can shorten the episode — but the sodium dose works best as a steady drip, not a fire extinguisher.

How many Kaiju sticks should I take to prevent cramps?

Most heavy sweaters take one stick (500 ml) before a long session, one per hour during, one after. Salty sweaters often need two per hour during heat or hard efforts. The 60-second sweat test gives you a personalised number.

What's the difference between Kaiju and regular electrolyte tabs for cramps?

Most tablets deliver ~100 mg of sodium per serving. Kaiju delivers 593 mg — about 10× higher. Heavy sweaters can lose 4,000+ mg per hour. The standard low-dose tab doesn't move the needle on cramps. Kaiju does.

Can I use Kaiju for night-time leg cramps?

Yes — many users report fewer overnight cramps after starting Kaiju in the evening, especially after hot training days. The sodium and magnesium bisglycinate support muscle and nerve recovery during sleep.

Is Kaiju safe for tested athletes?

Yes. Every batch is independently tested by Informed Sport against the WADA prohibited substances list. Safe for athletes under anti-doping rules.