RaceDayPace
Personal Essay

Why Most Half Marathon
Blowups Start Early

Every bad race has a common root. Looking back at late-race collapses, the mistakes were almost always made in the first few miles — not the last.

5 min readMay 2026

Looking back on the half marathons where I've blown up late, it honestly was never because I slept badly the night before or forgot my favorite race outfit.

Every bad race I can remember came down to one of two things.

1

Going Out Too Fast

Adrenaline and crowd energy make early miles feel effortless. Runners convince themselves to push sooner than planned — and pay for it around mile 10 or 11.

2

Underfueling

Waiting until you feel terrible is too late. Fueling works proactively, not reactively. By the time you feel depleted, it's already affecting your pace.

That's really it.

Why the First Miles Are So Deceptive

The first few miles of a half marathon can feel incredible. You feel fresh, adrenaline is high, the crowd energy is pulling you along, and goal pace can feel almost effortless.

"I feel amazing today, I can push earlier."

— The thought that has ended many races early

Almost every time that decision gets made, it comes back late — around mile 10 or 11 — when the legs that felt so good at mile 2 suddenly stop cooperating.

On the other hand, the races where I stayed patient early almost always ended up being stronger overall performances.

Practice Fueling During Training — Not on Race Day

Your long runs are basically dress rehearsals for race day. Don't wait until race morning to figure out what works.

What to Practice on Long Runs

Practice gels during long runs to know what works for you
Learn your exact water needs before race day
Test fueling timing — when to take gels relative to effort changes
See how your stomach reacts during harder-paced long runs
Treat long runs as dress rehearsals, not just mileage accumulation

Patience Is a Race-Day Skill

Practicing pacing discipline during opening miles is just as important as any workout. Here's what I've learned from races that went well.

Let people pass you early

Many runners flying by in the first mile are the ones you'll catch later once fatigue sets in.

Feel like it's "too easy" early

That feeling during the first couple miles usually means your pacing is correct. Trust it.

Don't try to bank time

You'll get that time back naturally if you stay controlled and finish strong. Banking time early almost never works.

There's also a huge mental boost that comes from passing fading runners late in a race while still feeling relatively controlled yourself. That only happens if you paced well early.

Small Mistakes Compound Over 13.1 Miles

Most late-race blowups aren't random. They're usually small mistakes made early that slowly compound over the course of the race.

The Takeaway

Go slower than you think you should in the first few miles. Almost feeling like things are "too easy" early usually means you're pacing correctly. Stay patient, fuel early, and let the race come to you.

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