We forget to train this very important organ…
Reflecting on a hard-learned lesson from the WA Masters Athletic Club Half Marathon at Applecross Foreshore.
My gut had other plans.
Here’s why training your gut is as crucial as your long runs for half and full marathons, plus the latest elite research and dietician tips to fuel smart.
My Gut Check at Applecross
My coach threw me into the half with minimal long-run prep.
The plan?
Hold 4:00 min/km. But I hadn’t carb-loaded during training runs, nor practiced handling the 600g of carbs (8–10g/kg body weight) needed in the 36 hours before a half marathon.
Despite eating 2,500+ calories daily with plenty of carbs (think YoPRO yogurt, bread, fruit, lollies & oats), my gut rebelled. By KM 14, a headwind, weak conditioning and hitting the wall in glycogen stores saw my pace drop to 4:20+ min/km.
I finished in 1:26:59, fifth place, just shy of my PB.
Lesson? An untrained gut is a disaster waiting to happen.
Why Train Your Gut?
Carb-loading for half and full marathons (races >90 minutes) boosts glycogen stores, delaying fatigue and helping you avoid “hitting the wall.” Research shows carb-loading can improve performance by 2–3% by maximizing muscle glycogen, which fuels 60–90 minutes of running.
But cramming 8–12g/kg of carbs (e.g., 560–840g for a 70kg runner) in less than two days without practice can cause bloating, cramps, or worse, mid-race GI distress. Elite runners train their gut during long runs to adapt to high-carb intake, using gels, chews, or sports drinks (30–90g carbs/hour) to optimize absorption and minimize stomach issues.
Elite Fueling Strategies for Half & Full Marathons
Recent studies and sports dieticians emphasize a strategic approach:
Carb-Loading (2 Days Pre-Race): Aim for 8–10g/kg body weight daily (e.g., rice, pasta, oats, low-fiber fruits like bananas). A 2024 study found runners consuming >7g/kg the day before a marathon ran 13.4% faster. Start tapering mileage 3–6 days out to store glycogen without burning it.
Train Your Gut: Practice carb-loading and in-race fueling (gels, chews, or drinks with 30–60g carbs/hour for half marathons, up to 90g/hour for marathons) during long runs. A 2024 study showed frequent gel intake (every 30–45 minutes) improved half marathon performance by maintaining blood glucose. Use multiple transportable carbs (glucose + fructose) to enhance absorption.
Race Day: Eat a familiar, carb-rich breakfast (1–4g/kg, e.g., oatmeal with honey) 2–4 hours before, and a 25–30g carb snack (e.g., Energy Chews) 5–10 minutes pre-race. During the race, aim for 50–70g carbs/hour for faster runners (sub-3-hour marathon) to sustain pace.
Hydration & Electrolytes: Pair carbs with 400mg sodium/hour and 8–16oz fluid to avoid dehydration or GI issues.
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Keep running,
Alistair Chegwidden
@Chegitout | #TheRunMaker