Hami Mahani

Marathon Week Mistakes: 9 Things That Quietly Ruin Race Day

You did the training — don't lose the race in the final week. The 9 most common marathon-week mistakes, from late carb loads to expo legs, and the simple fix for each one.

You trained for 16, 18, maybe 20 weeks. You hit the long runs in the dark, you figured out your fueling, you earned the taper. And then marathon week arrives — and this is, honestly, where I see more good races quietly unravel than at mile 20.

They care too much in the final seven days — they test, they tinker, they add. With the NYC Marathon five days out, here are the nine mistakes I watch for in my own race weeks, and the fix for each.

1. Trying Something New — Anything New

New shoes, new socks, a new breakfast, a gel flavor someone handed you at the expo. Race week is not the week to experiment. Your body is a system you have spent months calibrating. Every new variable is a gamble you do not need to take.

The fix: If you did not train with it, it does not race with you. Lay out exactly what worked on your best long run — same shoes (or the same model with low miles), same socks, same fuel, same breakfast — and repeat it. Boring is fast on race day.

2. Testing Your Fitness in the Taper

The taper feels wrong, and suddenly you want to prove you are still fit with one hard workout. Do not. Fitness is already banked — nothing this week makes you faster, but one hero session can leave fatigue in your legs on Sunday.

The fix: Follow the taper as written: shorter, easier, with a few short strides to stay sharp. A proper shakeout run the day before — 15 to 20 minutes, very easy — is the last run that matters. Trust the work you already did.

3. Starting Your Carb Load Too Late (or Barely Doing It)

The classic version of this mistake: a normal week of eating, then one giant pasta dinner the night before and a stomach full of regret. Carb loading is a three-day process, not a single meal. Your muscles need time to actually store the glycogen.

The fix: Start three days out, shift your plate toward carbs at every meal, and keep fiber and fat lower in the final 24 hours so your stomach is calm. I break down the exact days and amounts in our 3-day carb load plan, and the broader picture in taper week nutrition. Eat like it is part of training — because it is.

4. Walking the Expo Like It Is a Second Job

Three hours on concrete in street shoes the day before 26.2 miles is real, avoidable leg fatigue. Add a skipped lunch and low hydration, and you start already depleted.

The fix: Get in, get your bib, take your photo, get out. Sit as much as you can the rest of the day, keep a bottle in your hand, and use our day-before checklist so nothing is left to a last-minute store run.

5. Panicking About Sleep on the Wrong Night

Almost nobody sleeps well the night before a marathon. The good news: that night matters far less than the night two nights before. One short night will not undo a training block.

The fix: Bank sleep Thursday and Friday, protect Friday night especially, and stop stressing about Saturday. We covered the science and the routine in how to sleep before a marathon. Rest is a skill — practice winding down early all week.

6. Gambling on Race-Morning Breakfast

Race morning is not the time for a hotel buffet experiment. Too much, too late, too much fiber or fat — all of it shows up around mile 8.

The fix: Eat the breakfast you rehearsed before your long runs, 2 to 3 hours before the start, mostly simple carbs, low fiber, low fat. If you need a refresher, our guide on what to eat the morning of a marathon has the exact protocol I use.

7. Ignoring the Small Stuff: Skin, Feet, and Weather

Blisters, chafing, and being dressed wrong for a 38-degree start that becomes 55 by mile 18 — these feel small on Tuesday and enormous at mile 22. Race week is when you solve them, not race morning.

The fix: Trim toenails early in the week (not the night before), plan your anti-chafe routine, and decide your layers and throwaway clothes in advance. Our guides on preventing blisters and chafing and what to wear in cold weather cover both in detail.

8. Going Out Too Fast Because You Feel Amazing

Tapered legs, carb-loaded muscles, crowds screaming — the first miles will feel effortless. That feeling is a trap. Every minute you bank too early is repaid with interest after mile 20, which is exactly how hitting the wall happens.

The fix: Write your pacing plan down this week, not at the start line. Know your first-5K split and protect it. If you are racing New York, our NYC course strategy and general marathon pacing guide will help you run the bridges and boroughs the smart way.

9. Having No Fueling Discipline — and No Recovery Plan

Two sides of the same mistake. During the race, runners wait until they feel empty to start fueling — by then it is too late, because your gut needs fuel before the tank runs dry. And after the race, they collapse, skip food for hours, and wonder why the next week hurts so much.

The fix: Start fueling early — by 30 to 45 minutes in — and stay on a schedule, roughly every 20 to 30 minutes, whether you feel like it or not. This is where I am honest about what I personally use: I built 6AM Run Marathon Gummies for my own races because gels left me with sticky hands and a stomach that quit before my legs did. Gummies are portable, easy to chew in small amounts, and gentler for me — but if gels work for your gut and you trained with them, stay with gels. The best fuel is the one you practiced, which is the whole point of training your gut.

After the finish, get carbs and protein in within the first hour, keep walking, and follow a real plan for the week — our first 7 days recovery guide lays it out hour by hour. Personally, that first hour is when I take FinishLine, our amino recovery blend, because I want to start repairing while I am still at the finish festival instead of waiting until I get home. Whatever you use, use something early — recovery starts at the finish line, not the next morning.

The Marathon Week Rule I Actually Live By

Subtract, do not add. Fewer decisions, fewer experiments, fewer miles, more food, more rest, more sitting down. Your training made you ready. This week, your only job is to arrive at the start line with that readiness intact.

Your turn: What is the one marathon-week mistake you have made — or the one ritual you swear by in race week? Tell me in the comments. I read every one, and the best ones end up helping the next runner in this club.

— Hami, 6AM Run