Supplements for Runners — Running Nutrition | 6AM Run

Mile 20 is not magic. It just feels that way. Two miles later your legs feel like concrete, your brain gets foggy, and every step becomes a negotiation. Runners call it hitting the wall, or bonking. The good news: it is rarely bad luck. It is almost always math, pacing, and practice — and all three are fixable before your next race.

What hitting the wall actually is

Your body stores carbohydrate as glycogen in your muscles and liver — roughly 1,600 to 2,000 calories' worth if you start fully loaded. At marathon pace, most runners burn through that store in about 18 to 22 miles. Fat can fuel running too, but not at marathon-pace effort. When glycogen runs low, your body has to slow down to the speed fat can support. That sudden slowdown is the wall. It does not mean your training failed. It means the tank emptied faster than you refilled it.

Dehydration, heat, and going out too fast make it arrive earlier — ten miles run 15 seconds per mile too fast can move your wall from mile 23 to mile 18.

Fix 1: Start the race with a full tank

You cannot fuel your way out of starting empty. In the two to three days before a marathon, shift your meals toward carbohydrate — pasta, rice, bread, potatoes, oatmeal, fruit — while keeping protein and fat moderate. Aim for carbs at every meal, plus a carb-based evening snack, and drink to thirst so you start hydrated.

Race morning matters just as much. Eat a familiar, mostly-carbohydrate breakfast two to three hours before the start — the full routine is in my guide to what to eat the morning of a marathon. Then top off with a small carbohydrate in the last 30 minutes before you start.

Fix 2: Fuel early, fuel on a schedule — not when you feel hungry

This is the mistake I see most, and the one I made myself: waiting until mile 10 or 12 to take the first fuel because the early miles feel easy. By the time you feel low, you are already behind, and your stomach absorbs carbohydrate more slowly late in a race. Start fueling in the first 30 to 45 minutes and keep taking carbohydrate every 20 to 30 minutes after that, whether you feel like you need it or not. Set a watch alert — treat it like a schedule, not a craving.

How much? Most runners do well on 45 to 75 grams of carbohydrate per hour, and well-trained stomachs can handle 90 grams or more. A typical gel, serving of chews, or handful of gummies carries roughly 20 to 25 grams, so think two to three servings an hour, every hour, from early on. For your personal number by weight and pace, use our Marathon Fueling Calculator before race week.

Format is personal. Gels deliver carbs fastest but can be sticky late in a race; chews and gummies let you graze a little at a time, which many runners find easier on the stomach. I compared the honest trade-offs in gels vs. gummies vs. chews — the best fuel is the one you will actually take at mile 22.

Fix 3: Practice your race fueling on every long run

Your gut is trainable, just like your legs. Every long run in the final eight weeks should rehearse race day: same breakfast timing, first fuel at the same minute, same amount per hour, same products, carried the same way. Start around 40 grams an hour and build up week by week. If something upsets your stomach at mile 14 of a training run, that is useful information you got for free — finding out at mile 14 of your marathon is expensive.

Practice the logistics too: opening packets with sweaty hands, carrying enough for four-plus hours, what you do if you drop one. On my own long runs I carry Marathon Gummies because I can take a few at a time with no sticky mess and they sit well on my stomach at 6 AM — that is what works for me. If a gel works better for you, use that. The brand matters far less than starting early, taking enough, and having practiced it.

Fix 4: Pace like you want a last 10K, not a first 10K

No fueling plan survives a reckless start. The first miles should feel almost too easy — crowds, fresh legs, and adrenaline lie to you. Every second banked early costs far more later. Run the first 5K at, or a touch slower than, goal pace, settle in by mile 5, hold through mile 18, and only then decide what you have left.

On hills and into wind, run effort, not pace. Surges are glycogen-expensive, and you will want that glycogen at mile 24.

If you feel the wall coming anyway

If your pace is slipping and your head feels fuzzy, act immediately: take carbohydrate right away, plus water or sports drink at the next aid station. Slow down for a mile on purpose rather than grinding to a stop — a controlled slowdown lets that fuel start working, and the fog often lifts within ten minutes. Shorten your focus to the next mile marker. And never stop fueling because the finish feels close; the last 5K is when it matters most.

Afterwards, log what you ate the day before, what you took per hour, and where the pace first slipped — that log is your plan for next time. Recovery starts at the finish: carbohydrate and protein within the hour, electrolytes, then a real meal. On my own race days I use Finishline aminos as part of that first step — my routine; any protein-and-carb meal you enjoy does the main job.

Your anti-wall checklist

• Carb-load for 2–3 days; make every meal carb-led.
• Eat a familiar race-morning breakfast 2–3 hours before the start.
• Start fueling at 30–45 minutes — on a schedule, not on hunger.
• Target 45–75 grams of carbohydrate per hour (more only if practiced).
• Rehearse the exact plan, products, and carrying system on long runs.
• Run the first 5K controlled; pace by effort on hills and in wind.
• If the fog comes: fuel immediately, slow for one mile, keep moving.

The wall feels personal, but it is really just an empty tank and an honest pace away from disappearing. Fill the tank, refill it early and often, practice the plan, and mile 20 becomes just another mile — the one where you start passing people. See you out there.

— Hami, 6AM Run