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The Day Before Your Half Marathon: What to Eat, How to Rest, and What to Avoid (Especially at Altitude)

half marathonrace prepaltitude trainingBogota runningtaperrace day nutrition
The Day Before Your Half Marathon: What to Eat, How to Rest, and What to Avoid (Especially at Altitude)

Photo by Jozsef Hocza on Unsplash

The half marathon is a distance people love to underestimate — and doing it in Bogota, with altitude and a brutal elevation profile, punishes that mistake fast. Here's exactly what to do 24 hours out, from your last training session to your shoelaces.

Let's Get One Thing Straight: The Half Marathon Is Not a "Long Run With a Number Pinned On"

I see this every season. Runners treat the 21.1K like it's a stepping stone distance — not quite a marathon, so it doesn't deserve marathon-level respect. That's a mistake. The half punishes bad pacing, bad fueling, and bad taper decisions just as harshly as its bigger sibling, just faster. And if you're racing in Bogota — altitude around 2,600m, with rolling hills that never let your legs settle into a rhythm — the margin for error shrinks even further.

Here's the good news: if you've trained properly, you are already fit. The work is done. Fitness doesn't disappear in 24 hours. What can disappear — fast — is that fitness expressing itself on race day, because of poor sleep, bad nutrition timing, or an ill-advised "shake out" that turns into an accidental tempo run. This is the day we protect the investment.

Why You Should Feel Strong Right Now (And Why That's Science, Not Vibes)

If your training block was built correctly, you should be feeling primed, not fatigued, the day before the race. This isn't wishful thinking — it's supercompensation theory in action. The taper period allows accumulated fatigue to dissipate while fitness adaptations remain, which is why well-tapered runners consistently outperform their training paces on race day.

This is also why monitoring how your body is actually responding matters more than trusting a spreadsheet blindly. Modern exercise science increasingly uses biomarkers to track how the body is truly recovering and adapting to training load — not just how many miles you logged [PMID:41922043]. I tell my athletes: the plan is a hypothesis, your body's response is the data. If you're still carrying heavy soreness or your resting heart rate is elevated the day before, that's information, not something to push through with one more hard effort.

The Physical Session You SHOULD Do

Yes, you should move. No, you should not

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