Endurance 101 - Endurance Nutrition Made Simple

Endurance fueling is one of the most important factors in performance for runners, cyclists, and

triathletes. Knowing how many carbs per hour to consume, how to manage electrolyte intake, and what foods to use during long sessions can prevent energy crashes and improve endurance. This guide breaks down endurance nutrition in a simple, practical way—covering carbohydrate needs, hydration strategies, and real food fueling options for training and race day How to Fuel Properly for Endurance Sport: Carbs, Electrolytes & Real Food (Made Simple)

If you’ve ever hit the wall mid-run, ride, or race—you’ll know it’s not just about fitness.

It’s fuelling.

Most endurance athletes don’t struggle because they’re unfit. They struggle because they’re under-fuelled, over-fuelled, or incorrectly fuelled.

The good news? Once you understand how carbs, fluids, and electrolytes work together, everything starts to click. Your energy stabilises. Your effort feels more controlled. And those late-session fades? They become far less dramatic.

Let’s walk through it in a practical, no-nonsense way.

Why Fuelling Matters More Than You Think

Your body uses a mix of fat and carbohydrates for energy. But when intensity increases—even slightly—carbohydrates become the dominant fuel source.

The problem is:👉 Your body can only store a limited amount (glycogen)

So during longer sessions, you’re constantly burning through that supply. If you don’t replace it?

You “bonk.”

That heavy-legged, slow-motion feeling where even easy pace feels hard—that’s your body running low on usable fuel.

Step 1: How Many Carbs Do You Actually Need?

Let’s simplify this.

General guidelines based on duration:

• Under 60 minutes You’re fine with just fluids

• 1–2 hours 30–60g carbs per hour

• 2–3+ hours 60–90g carbs per hour

• Ultra endurance (3+ hours, trained athletes) 90–120g carbs per hour (only if your gut is trained)

A simple formula you can actually use:

Body weight (kg) × 0.8 = carbs per hour

So if you weigh 70kg:→ 70 × 0.8 = ~56g carbs/hour

That’s your starting point—not a fixed rule.

From there, you adjust based on:

• Intensity (easy vs race pace)

• Conditions (heat increases needs)

• Gut tolerance (this is big)

Step 2: Electrolytes — The Missing Piece 💧

A lot of athletes focus only on carbs… and then wonder why they cramp, feel dizzy, or can’t stomach their nutrition.

That’s usually an electrolyte issue.

When you sweat, you lose:

• Sodium (main one)

• Chloride

• Potassium

And sodium is critical for:

• Fluid absorption

• Muscle function

• Preventing cramping

How much do you need?

• Sodium: 300–600mg per hour (baseline) 800–1000mg/hour in heat or heavy sweating

• Fluids: 400–800ml per hour

Real-world signs you’re low on electrolytes:

• Salt stains on clothes

• Headaches

• Muscle cramps

• Feeling “flat” despite eating

Step 3: What Does 60g of Carbs Actually Look Like?

This is where things become practical.

Here are common foods with carbs per 100g so you can mix and match:

🍌 Fruits

• Banana → 23g carbs / 100g

• Apple → 14g carbs / 100g

• Orange / Naartjie → 12g carbs / 100g

• Dates → 75g carbs / 100g

• Raisins → 79g carbs / 100g

• Dried apricots → 63g carbs / 100g

👉 Dried fruit = compact, high-carb, race-friendly 👉 Fresh fruit = more hydrating but bulkier

🥔 Simple Whole Foods

• Boiled potatoes → 17g carbs / 100g

• Sweet potatoes → 20g carbs / 100g

• White rice (cooked) → 28g carbs / 100g

• White bread → 49g carbs / 100g

• Honey → 82g carbs / 100g

• Jam → 60–65g carbs / 100g

🧪 Sports Nutrition

• Energy gels → ~60–70g carbs / 100g

• Sports drinks → 6–8g carbs per 100ml

Step 4: Putting It Together (Real Example)

Let’s say you’re aiming for 70g carbs per hour.

You could do:

• 1 medium banana (120g) → ~28g carbs

• 30g raisins → ~24g carbs

• 250ml sports drink → ~15g carbs

Total: ~67g carbs/hour

Simple. No overthinking.

Step 5: Real Food Fuelling (That Actually Works)

You don’t need to rely only on gels.

In fact, many athletes perform better mixing in real food.

Easy, stomach-friendly options:

• Bananas

• Naartjies (great in South African races)

• Boiled potatoes with salt

• Rice balls with honey

• White bread + jam

For A More in depth explanation about electrolytes VS Carbs for fuelling Read HERE Step 6: Homemade Fuel Options (Highly Underrated)

If you want control over ingredients (and cost), these are gold: (Recipe's at the end)

🍯 Oat & Honey Bars

Carb density: ~55–65g per 100g

Made from oats, honey, peanut butter, and dried fruit.

👉 Great for training and longer steady sessions

🍚 Rice Cakes

Carb density: ~35–50g per 100g

White rice + honey + pinch of salt

👉 Easy on the stomach, very race-friendly

🥜 Date Energy Balls

Carb density: ~60–70g per 100g

Dates + oats (blended)

👉 High energy, small volume, very effective

Step 7: Train Your Gut (This Is Where Performance Is Won or Lost)

Here’s the truth most people don’t realise:

Your gut is trainable—just like your legs, heart, and lungs.

If you’ve ever struggled with bloating, nausea, or “food just sitting in your stomach” during a run, it’s not just bad luck. It’s often because your digestive system hasn’t been trained to handle fuel during exercise.

When you train your gut properly:

• You absorb more carbs per hour

• You reduce the risk of GI distress

• You can sustain higher intensities for longer

🧠 What’s actually happening?

During exercise:

• Blood flow is redirected away from your gut to your muscles

• Digestion slows down

• Absorption becomes limited

But with consistent practice, your body adapts by:

• Improving gastric emptying (food leaves the stomach faster)

• Increasing transporter capacity for carbs (especially glucose + fructose)

• Reducing sensitivity to food intake under stress

📈 How to Train Your Gut (Step-by-Step)

1. Start Lower Than You Think

Begin with: 👉 40–50g carbs per hour

Even if your goal is 80–90g/hr.

2. Progress Gradually

Increase intake slowly: 👉 Add ~10g carbs per hour every 1–2 weeks

Example progression:

• Week 1–2: 50g/hr

• Week 3–4: 60g/hr

• Week 5–6: 70g/hr

3. Practice in Key Sessions Only

You don’t need to fuel every run.

Focus on:

• Long runs

• Race-pace workouts

• Brick sessions (for triathlon)

4. Match Race Conditions

Train your gut under:

• Similar intensity

• Similar heat

• Similar hydration strategy

Your race day should feel familiar—not experimental.

5. Mix Your Carb Sources

Your body absorbs more when you combine:

• Glucose sources (rice, bread, sports drink)

• Fructose sources (fruit, honey)

👉 This allows higher intake (up to 90g/hr+)

6. Practice Timing

Instead of large infrequent feeds: 👉 Aim for small amounts every 15–20 minutes

This improves absorption and reduces gut overload.

7. Listen and Adjust (Not Everything Is “Push Through”)

There’s a difference between:

• Mild discomfort (normal during adaptation)

• Severe bloating, cramping, nausea (needs adjustment)

If something isn’t working:

• Reduce intake slightly

• Change food type

• Adjust fluid intake

⚠️ Common Gut Training Mistakes

• Jumping straight to high carb intake

• Only using gels without practicing

• Ignoring hydration while increasing carbs

• Trying new foods on race day

• Not being consistent with practice

Real-World Context

If you’re preparing for something like the Comrades Marathon, your fuelling becomes just as important as your training.

A smart strategy might look like:

• 60–70g carbs/hour early on

• Build toward 75–90g/hour

• Combine fluids, electrolytes, and real food

Because over that kind of distance, small mistakes compound.

The Simple Takeaway

If you strip it all down:

👉 Carbs fuel your engine 👉 Electrolytes keep the system running 👉 Your gut determines how much you can actually use

Start with:

• Body weight × 0.8 = carbs/hour

• 300–600mg sodium/hour

• 400–800ml fluid/hour

Then train your system to handle it.

Final Thought

Fuelling isn’t just about avoiding the crash—it’s about unlocking consistency.

When you get this right:

• Your pace stabilises

• Your energy lasts

• Your performance improves

And instead of just getting through your session…

You actually finish strong. BONUS SECTION: RECIPE'S

🍯 Oat & Honey Energy Bars Ingredients

• 2 cups rolled oats

• ½ cup honey

• ¼ cup peanut butter

• ¼ cup dried fruit (raisins or chopped dates)

• Pinch of salt

Method

1. Mix all ingredients in a bowl until well combined

2. Press firmly into a lined tray

3. Refrigerate for 1–2 hours

4. Cut into bars

Fuel Notes

• ~55–65g carbs per 100g

• Great for long steady sessions

• Easy to carry, not overly sweet

🍚 Rice Cakes (Endurance Favourite) Ingredients

• 2 cups cooked white rice

• 2–3 tbsp honey or maple syrup

• Pinch of salt

Optional:

• Mashed banana

• Small amount peanut butter

Method

1. Mix rice, honey, and salt while rice is still slightly warm

2. Press into a tray or container

3. Chill in fridge until firm

4. Cut into squares and wrap individually

Fuel Notes

• ~35–50g carbs per 100g

• Very easy on the stomach

• Ideal for long runs or races

🥜 Date Energy Balls Ingredients

• 1 cup pitted dates

• ½ cup oats

• 1 tbsp cocoa powder (optional)

• Pinch of salt

Method

1. Blend everything in a food processor

2. Roll into small bite-sized balls

3. Store in fridge

Fuel Notes

• ~60–70g carbs per 100g

• High energy in small volume

• Great for higher intensity or later stages of sessions

🍌 Simple Real Food Combos (No Prep Needed)

Easy Options

• Banana + handful of raisins

• Dates + sip of sports drink

• White bread + honey/jam

Fuel Notes

• Flexible and accessible

• Great to mix with gels/drinks

• Helps prevent flavour fatigue