Carb Loading for a Marathon: What the Science Actually Says
October 15, 2026
How much to eat, when to start and what to eat for a marathon carb load, plus what the newest research says about whether it actually makes you faster.
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Latest article
Latest article · Nutrition
15 October 2026 · 9 min read
Read article →TL;DR
Carb loading reliably fills your muscles with more glycogen, and 2026 research shows more carbs meant more stored fuel, up to about 10 g per kg a day.
Whether that makes you faster is less certain than marathon culture suggests. The mechanism makes sense and the risk is low, so if your race is longer than about 90 minutes, load with the right foods.
Latest article · Nutrition
13 October 2026 · 9 min read
TL;DR
That shaky, starving, raid-the-cupboards feeling after a long ride gets called a “sugar crash”, but it’s almost always underfuelling.
Set an hourly carb target, pack more food than you think you’ll need, and have recovery food ready for when you get in. It’s your body asking for the fuel it didn’t get.
FuellingBonkingRecovery
All articles
How much to eat, when to start and what to eat for a marathon carb load, plus what the newest research says about whether it actually makes you faster.
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