• Kaiju - 10 sticks box
1 8
OSMØ®
ANTI-CRAMP FORMULA

RUNNER HYDRATION STICK

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

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

Stops cramping
593 mg of sodium per serving. Designed for runners.
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 run 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 runners need more sodium than they think

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 running 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 runners 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 runners say

4.8 ★ from 87 reviews on Trustpilot

Better than the rest
★★★★★

"Tried several brands. Kaiju is the only one that doesn't taste like sweet flavoured water and actually works."

Anna K.

Marathon runner · London

Sceptic converted
★★★★★

"Was sceptical because of the price. Used it through marathon training. Worth every euro."

David R.

Marathon runner · Paris

Better than the rest
★★★★★

"Tried several brands. Kaiju is the only one that doesn't taste like sweet flavoured water and actually works."

Anna K.

Marathon runner · London

Sceptic converted
★★★★★

"Was sceptical because of the price. Used it through marathon training. Worth every euro."

David R.

Marathon runner · Paris

Better than the rest
★★★★★

"Tried several brands. Kaiju is the only one that doesn't taste like sweet flavoured water and actually works."

Anna K.

Marathon runner · London

Sceptic converted
★★★★★

"Was sceptical because of the price. Used it through marathon training. Worth every euro."

David R.

Marathon runner · Paris

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 during your run

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

What Kaiju does for you?

Stops you bonking

Sustained sodium where standard tabs run out. Built for runners.

No more cramps

Replaces the salt your body actually loses during a run.

No headaches after hot sessions

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

Bounce back next morning

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

FAQ

How many Kaiju sticks should I take during a marathon?

Most heavy-sweater runners take one stick (500 ml) before the race, then one stick per hour during, then one after. For lighter sweaters, one before and one mid-race is usually enough. Use the 60-second sweat test to dial it in.

Will Kaiju stop me cramping in the back half of a marathon?

Most race-day cramps are sodium-driven. Each stick delivers 593 mg — about 10× a typical sports drink. Sipped steadily through the race, most heavy-sweater runners using Kaiju report no more cramping at mile 20.

Is Kaiju good for trail and ultra running?

Yes. The dose, the lack of sugar, and the magnesium bisglycinate form make it well-suited to multi-hour trail and ultra efforts. Mix into a soft flask or vest reservoir.

Can I use Kaiju for hot-weather marathon training?

Yes — hot-weather training is where the 593 mg sodium dose earns its keep. Heavy sweaters can lose 4,000+ mg per hour in heat. Start with one stick per long run; scale to 2 per hour for hot Saturday efforts.

Should I take electrolytes before, during, or after a long run?

All three for sessions over 90 minutes. One bottle to start hydrated, one or two per hour during, one after to begin recovery and reduce the next-day headache.

Why no sugar? I get my carbs from gels.

Exactly. Kaiju is built for hydration, not fuel. Your carbs come from gels, bars, or real food during the run. Doubling up sugar in the electrolyte makes both jobs worse.

Is Kaiju safe for tested runners (UKA, USATF, WADA)?

Yes. Every batch is independently tested by Informed Sport against the WADA prohibited substances list.