Sweatr

Sweatr blog

The science behind performing on race day

Guides, deep-dives, and practical advice for runners, cyclists, and triathletes who want to get their fueling right.

Summer Cycling Hydration: Why Your Bottle-Per-Hour Rule Breaks Down Above 30°C
Hydration Science

Summer Cycling Hydration: Why Your Bottle-Per-Hour Rule Breaks Down Above 30°C

Your one-bottle-per-hour habit worked in spring. Here's why it fails in summer heat and how to calculate what you actually need.

11 July 20267 min
Your Watch Knows You're Overheating — Here's How to Adjust Your Hydration Mid-Run
Hydration Science

Your Watch Knows You're Overheating — Here's How to Adjust Your Hydration Mid-Run

Your wearable data reveals when heat is draining you faster than planned. Learn to read those signals and adjust your hydration before it's too late.

9 July 20268 min
Electrolyte Tablets vs Drink Mixes vs Salt Caps: Which Format Matches Your Sweat?
Hydration Science

Electrolyte Tablets vs Drink Mixes vs Salt Caps: Which Format Matches Your Sweat?

Stop comparing brands. The format you choose matters more — here's how to pick the right one for your sweat rate and race.

30 June 20269 min
Do You Need Electrolytes on Every Run?
Hydration Science

Do You Need Electrolytes on Every Run?

A sweat-rate-based guide to when electrolytes matter, when water is enough, and how to stop guessing.

26 June 20269 min
Why You Need a Different Hydration Plan for Every Type of Workout
Hydration Science

Why You Need a Different Hydration Plan for Every Type of Workout

Your easy jog and your tempo run demand completely different hydration. Here's how to match your fluid intake to workout intensity.

24 June 20268 min
You're Probably Dehydrated Before Your Long Run Even Starts
Hydration Science

You're Probably Dehydrated Before Your Long Run Even Starts

Most hydration advice focuses on race day. The real problem starts 24 hours earlier in your daily training.

23 June 20268 min
Why Summer Heat Wrecks Your Gut on Long Runs — and How to Fuel Through It
Hydration Science

Why Summer Heat Wrecks Your Gut on Long Runs — and How to Fuel Through It

Heat redirects blood from your gut, killing your ability to absorb fuel. Here's the science and a protocol to fix it.

18 June 20269 min
How Heat Acclimatisation Changes Your Sweat — and Why You Need to Re-Test Every Summer
Hydration Science

How Heat Acclimatisation Changes Your Sweat — and Why You Need to Re-Test Every Summer

Your spring sweat rate is wrong by June. Here's what heat acclimatisation does to your body and how to recalibrate.

5 June 20268 min
Dehydrated or Overhydrated? How to Read the Signs Mid-Race
Hydration Science

Dehydrated or Overhydrated? How to Read the Signs Mid-Race

Learn to tell the difference between dehydration and overhydration during a race — and what to do before either one ruins your day.

25 May 20268 min
Your Hydration Plan Worked in April — Here's Why It Fails When Summer Hits
Hydration Science

Your Hydration Plan Worked in April — Here's Why It Fails When Summer Hits

Rising temps change everything about your sweat rate and sodium needs. Here's how to adapt before your next long run.

16 May 20268 min
How Much Should You Drink During a Half Marathon?
Hydration Science

How Much Should You Drink During a Half Marathon?

A personalised guide to half marathon hydration based on your sweat rate, pace, and race-day conditions.

15 May 20269 min
Every Sodium Guide Gives You a Range. Here's How to Find YOUR Number.
Hydration Science

Every Sodium Guide Gives You a Range. Here's How to Find YOUR Number.

Stop guessing between 300mg and 1500mg per hour. Here's how to find your personal sodium needs for running and racing.

9 May 20269 min
Sodium Loading Before a Marathon: How Much You Need and When to Start
Hydration Science

Sodium Loading Before a Marathon: How Much You Need and When to Start

Pre-race sodium loading boosts plasma volume and cuts cramping risk. Here's the exact protocol for the 48 hours before your marathon.

30 April 20269 min
Your Sweat Rate Isn't Fixed: How Fitness, Heat, and Humidity Change Everything
Hydration Science

Your Sweat Rate Isn't Fixed: How Fitness, Heat, and Humidity Change Everything

Sweat rate shifts with fitness, weather, and acclimatisation. Here's what changes, why it matters, and how to adjust.

28 April 20267 min
You Can Drink Too Much During a Marathon — Here's How to Stay in the Safe Zone
Hydration Science

You Can Drink Too Much During a Marathon — Here's How to Stay in the Safe Zone

Overhydration hospitalises runners every year. Learn how to find your personal fluid ceiling and avoid hyponatremia on race day.

23 April 20268 min
Drink to Thirst or Follow a Plan? Warm-Weather Marathon Hydration Without the Cramp or the Hospital
Hydration Science

Drink to Thirst or Follow a Plan? Warm-Weather Marathon Hydration Without the Cramp or the Hospital

How to avoid both cramping and hyponatremia when race day is hotter than you trained in — the middle path between drink-to-thirst and a rigid plan.

15 April 20268 min
Electrolytes for Runners: Which Ones Actually Matter and How Much You Need
Hydration Science

Electrolytes for Runners: Which Ones Actually Matter and How Much You Need

Sodium, potassium, magnesium — here's what each one does during a run, how much you lose in sweat, and how to stop guessing your dosage.

13 April 20266 min
How to Calculate Your Personal Sweat Rate (and Why Generic Hydration Advice Is Failing You)
Hydration Science

How to Calculate Your Personal Sweat Rate (and Why Generic Hydration Advice Is Failing You)

Your sweat rate is unique. Here's how to measure it at home and turn it into a hydration plan that actually works on race day.

10 April 20265 min
Why Do I Cramp During Marathons? The Science Your Watch Can't Tell You
Hydration Science

Why Do I Cramp During Marathons? The Science Your Watch Can't Tell You

Cramps ruined your race? Here's what actually causes them and how to build a hydration plan that fights back.

4 April 20266 min
How much should you drink during a marathon?
Hydration Science

How much should you drink during a marathon?

The generic answer is 500ml per hour. The right answer is calculated from your body weight, sweat rate, and how hard you're actually working. Here's how to find your number.

20 March 20264 min