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.

How to Read Your Body's Fuel Gauge Mid-Run: 7 Warning Signs You're Running Low
Fueling Strategy

How to Read Your Body's Fuel Gauge Mid-Run: 7 Warning Signs You're Running Low

Learn to spot the early signs of bonking, dehydration, and overheating before they wreck your race — and how to rescue the run.

25 August 20269 min
How to Fuel Your First 50K: The Ultramarathon Nutrition Plan That Starts With Your Watch Data
Fueling Strategy

How to Fuel Your First 50K: The Ultramarathon Nutrition Plan That Starts With Your Watch Data

Your marathon fueling plan won't work for a 50K. Here's how to build an ultra nutrition strategy using your wearable data.

21 August 20269 min
Why Your Running Buddy's Fueling Plan Won't Work for You
Fueling Strategy

Why Your Running Buddy's Fueling Plan Won't Work for You

Copying someone else's marathon nutrition is a gamble. Here's why fueling is personal and how to build a plan from your own data.

20 August 20267 min
How Hills Change Your Marathon Fueling Plan
Fueling Strategy

How Hills Change Your Marathon Fueling Plan

Hilly courses burn more carbs, shift your pacing, and change when you can take gels. Here's how to adjust.

18 August 20268 min
Why AI-Generated Marathon Nutrition Plans Get It Wrong
Fueling Strategy

Why AI-Generated Marathon Nutrition Plans Get It Wrong

ChatGPT can write a plausible fueling plan in seconds. Here's why it misses the data that actually matters on race day.

17 August 20267 min
How Much Fuel Do You Actually Need? A Body-Weight-Based Guide to Marathon Nutrition
Fueling Strategy

How Much Fuel Do You Actually Need? A Body-Weight-Based Guide to Marathon Nutrition

Stop guessing with the 60-90g/hour range. Calculate your personal fueling target based on body weight, pace, and conditions.

13 August 20267 min
Morning vs Evening Training: Why the Time You Run Changes How Much You Need to Fuel
Fueling Strategy

Morning vs Evening Training: Why the Time You Run Changes How Much You Need to Fuel

Glycogen, cortisol, and sweat rate all shift by time of day. Here's how to adjust your fueling.

11 August 20268 min
Why Your First 30 Minutes of Fueling Decide the Last 10K of Your Marathon
Fueling Strategy

Why Your First 30 Minutes of Fueling Decide the Last 10K of Your Marathon

Start fueling early or pay later. Here's why the first 30 minutes of your marathon set up the last 10K.

2 August 20269 min
Half Ironman Fueling: The Complete Nutrition Plan From Swim to Finish Line
Fueling Strategy

Half Ironman Fueling: The Complete Nutrition Plan From Swim to Finish Line

A leg-by-leg 70.3 nutrition plan with exact gram targets, timing cues, and the bike mistake that wrecks your run.

1 August 202611 min
Why Pace — Not Just Duration — Decides How Much Fuel You Need
Fueling Strategy

Why Pace — Not Just Duration — Decides How Much Fuel You Need

Your marathon fueling calculator ignores the biggest variable. Here's why pace changes your carb burn rate — and how to get the number right.

30 July 20269 min
Stop Taking a Full Gel Every 45 Minutes
Fueling Strategy

Stop Taking a Full Gel Every 45 Minutes

Smaller, more frequent gel doses reduce nausea and keep energy steadier. Here's how to find your personal rhythm.

28 July 20267 min
How to Fuel Back-to-Back Training Days — The Glycogen Debt Most Runners Ignore
Fueling Strategy

How to Fuel Back-to-Back Training Days — The Glycogen Debt Most Runners Ignore

Your Saturday long run empties the tank. Here's how to refuel so Sunday's session doesn't wreck your week.

25 July 20269 min
How to Fuel Long Runs When Your Appetite Disappears in Summer Heat
Fueling Strategy

How to Fuel Long Runs When Your Appetite Disappears in Summer Heat

Heat kills your appetite but raises your carb needs. Here's how to get fuel in when your body doesn't want it.

21 July 20268 min
You're Running a 4:30 Marathon. You Need More Fuel, Not Less.
Fueling Strategy

You're Running a 4:30 Marathon. You Need More Fuel, Not Less.

Slower marathoners spend longer on course, so total fuel demand equals or exceeds faster runners. Here's how to fuel properly.

20 July 20267 min
First Marathon Fueling Guide: What to Eat Before, During, and After Your Race
Fueling Strategy

First Marathon Fueling Guide: What to Eat Before, During, and After Your Race

A complete fueling plan for first-time marathoners — what to eat, when to eat it, and how to avoid the wall.

7 July 202610 min
What to Eat After a Long Run
Fueling Strategy

What to Eat After a Long Run

The 60-minute recovery window most runners miss — what to eat, when, and how much based on your actual effort.

5 July 20268 min
How to Fuel Easy Runs, Speed Work, and Long Runs — Why One Plan Doesn't Fit Every Workout
Fueling Strategy

How to Fuel Easy Runs, Speed Work, and Long Runs — Why One Plan Doesn't Fit Every Workout

Your training fueling should change with each workout type. Here's exactly what to eat and drink for easy runs, tempo sessions, and long runs.

4 July 202610 min
Drink Mix, Gels, or Both: How to Build Your Race-Day Fuel Stack
Fueling Strategy

Drink Mix, Gels, or Both: How to Build Your Race-Day Fuel Stack

High-carb drink mixes are changing race fueling. Learn when to use drink mix, gels, or both to hit your carb targets without GI distress.

2 July 202610 min
Your fueling plan should change every month of marathon training
Fueling Strategy

Your fueling plan should change every month of marathon training

Training load, heat, and fitness shift your carb and fluid needs. Here's how to adjust each month.

29 June 202610 min
Your Triathlon Run Fell Apart — Trace It Back to the Bike
Fueling Strategy

Your Triathlon Run Fell Apart — Trace It Back to the Bike

Most triathlon run blowups start on the bike. Here's how to fix your bike nutrition so the run doesn't fall apart.

27 June 20267 min
Glucose, Fructose, and Maltodextrin: Why the Type of Carb in Your Gel Matters More Than You Think
Fueling Strategy

Glucose, Fructose, and Maltodextrin: Why the Type of Carb in Your Gel Matters More Than You Think

Most runners count grams per hour but ignore carb type. Here's how glucose-to-fructose ratios set your absorption ceiling.

25 June 20268 min
Stop Guessing Your Race Nutrition: How to Build a Fueling Plan That's Actually Yours
Fueling Strategy

Stop Guessing Your Race Nutrition: How to Build a Fueling Plan That's Actually Yours

Every guide gives you ranges. Here's how to find your actual sweat rate, carb ceiling, and sodium needs.

19 June 20269 min
How to Fuel a Century Ride: A Cyclist's Complete Nutrition Plan for 100 Miles
Fueling Strategy

How to Fuel a Century Ride: A Cyclist's Complete Nutrition Plan for 100 Miles

A practical fueling and hydration plan for your century ride — carb targets, fluid timing, and what to carry for 100 miles.

10 June 202610 min
The 120g Carbs Per Hour Claim: What the Science Actually Shows
Fueling Strategy

The 120g Carbs Per Hour Claim: What the Science Actually Shows

Everyone's talking about 120g carbs per hour. Here's what the research really says and how to find the number that works for you.

4 June 20267 min
Caffeine in Your Racing Gels: How Much Helps, When to Take It, and When to Skip It
Fueling Strategy

Caffeine in Your Racing Gels: How Much Helps, When to Take It, and When to Skip It

A practical guide to caffeine dosing and timing in racing gels so you get the boost without the gut bomb.

22 May 20269 min
How to Find Your Personal Carb Ceiling — Why 90g Per Hour Isn't Right for Everyone
Fueling Strategy

How to Find Your Personal Carb Ceiling — Why 90g Per Hour Isn't Right for Everyone

The 60-90g carb advice is too vague. Here's how to find the number that actually works for your body, pace, and race distance.

17 May 20268 min
Do You Even Need Gels for a Half Marathon?
Fueling Strategy

Do You Even Need Gels for a Half Marathon?

A first-timer's honest guide to whether you need gels, how many, and when to take them during your half marathon.

14 May 20269 min
Hydrogels, Isotonic Gels, and Traditional Gels: Which One Should You Race With?
Fueling Strategy

Hydrogels, Isotonic Gels, and Traditional Gels: Which One Should You Race With?

A science-backed comparison of the three main gel types to help you pick the right fuel for your next race.

12 May 20269 min
Fueling a 3-Hour vs 5-Hour Marathon: Why One Plan Doesn't Fit All
Fueling Strategy

Fueling a 3-Hour vs 5-Hour Marathon: Why One Plan Doesn't Fit All

A 5-hour marathoner needs a completely different fueling strategy than a 3-hour runner. Here's exactly how pace changes everything.

10 May 20268 min
How to Train Your Gut to Handle 90g of Carbs Per Hour
Fueling Strategy

How to Train Your Gut to Handle 90g of Carbs Per Hour

A 12-week protocol to build carb tolerance for race day so you can fuel harder without GI distress.

3 May 20269 min
115 Grams Per Hour: What Sawe's Sub-2 Marathon Teaches You About Fueling
Fueling Strategy

115 Grams Per Hour: What Sawe's Sub-2 Marathon Teaches You About Fueling

Sawe fueled his 1:59 marathon on 115g carbs/hour. Here's what his protocol reveals about building your own race-day fueling plan.

29 April 20268 min
Real Food vs Gels: What Should You Actually Fuel With on Race Day?
Fueling Strategy

Real Food vs Gels: What Should You Actually Fuel With on Race Day?

Gels aren't the only option. Here's how to choose between real food and gels based on your pace, distance, and stomach.

26 April 20269 min
The 3 Biggest Nutrition Mistakes Runners Make in the Final 3 Weeks Before a Marathon
Fueling Strategy

The 3 Biggest Nutrition Mistakes Runners Make in the Final 3 Weeks Before a Marathon

Most marathoners sabotage race day before the gun fires. Avoid these three taper-phase nutrition mistakes.

25 April 20268 min
How to Fuel a Half Marathon: The Complete Plan by Finishing Time
Fueling Strategy

How to Fuel a Half Marathon: The Complete Plan by Finishing Time

Your half marathon fueling plan depends on your pace, not generic advice. Here's exactly what to eat and drink by finishing time.

22 April 20268 min
You Bonked at Mile 22 Despite a Fueling Plan — Here's What Went Wrong
Fueling Strategy

You Bonked at Mile 22 Despite a Fueling Plan — Here's What Went Wrong

Had a fueling plan and still hit the wall? These five mistakes explain why — and how to fix them before your next race.

20 April 20267 min
Why Your Energy Gels Make You Feel Sick — And How to Fix It
Fueling Strategy

Why Your Energy Gels Make You Feel Sick — And How to Fix It

Gel nausea isn't about the brand. It's about timing, carb load, and a gut that hasn't been trained. Here's the science and the fix.

15 April 20266 min
How Many Gels Per Hour Do You Actually Need? A Marathon Fueling Plan by Finishing Time
Fueling Strategy

How Many Gels Per Hour Do You Actually Need? A Marathon Fueling Plan by Finishing Time

Generic gel advice ignores your finishing time. Here is a per-hour fueling plan for sub-3 to 5-hour marathoners — plus why slower runners need more, not less.

7 April 20265 min
Why Do Gels Make You Feel Sick? How to Train Your Gut for Race Day
Fueling Strategy

Why Do Gels Make You Feel Sick? How to Train Your Gut for Race Day

GI distress ruins more races than tired legs. Here's the science behind gel nausea and a practical gut training protocol.

5 April 20266 min
When to take your first gel during a marathon
Fueling Strategy

When to take your first gel during a marathon

Most runners take gels too late, wait too long between them, and end up bonking despite carrying the right number. Here's the timing strategy that actually works.

14 March 20264 min