Do's and Don'ts for Running a Half Marathon
People train for a half marathon for all kinds of reasons — to see what 13.1 miles feels like, to build toward a full marathon, or just to try a shorter distance fast. Whatever brought you here, the same paired guidance applies across training and race day. Here's what to do, and what to avoid, organized by topic so you can scan straight to the part you need.
The Half Marathon Decision Table
| Topic | Do | Don't |
|---|---|---|
| Training | Build up gradually with long runs, easier recovery days, and a shorter tune-up race (5K or 10K) before race day | Skip structured training and rely on race-day adrenaline alone |
| Gear | Lay out tested shoes and clothing a few days early; break in anything new well before race week | Wear brand-new shoes or clothing you haven't run in |
| Pre-race meal | Eat a balanced meal with protein, carbs, and a little fat, 2-3 hours before the start | Eat within 1-2 hours of the gun, or eat greasy or high-sugar foods that can upset your stomach |
| Hydration | Drink steadily in the days leading into the race; a hydration calculator can estimate how much fluid you need, and the hydration strategy guide covers the full training-week approach | Wait until you're thirsty on the course to start drinking |
| Pacing | Know your goal pace ahead of time — a pace calculator turns a target finish time into an even mile split, and the half marathon pacing guide turns it into a full race plan | Charge off with the crowd in the first mile; a fast start almost always costs you late |
| Running form | Land on your midsole rather than your heel, and use planned run-walk intervals if that's part of your strategy | Ignore your form once fatigue sets in |
| Pain | Slow down or stop if pain shows up and gets worse as you go | Push through worsening pain hoping it fades — that's how a minor issue becomes an injury |
| Health | Get a medical checkup before ramping up training, especially with any existing condition | Attempt your first half marathon without ever having a checkup |
| The night before | Stay hydrated, eat normally, and get to bed at a reasonable hour | Drink alcohol — the dehydration and poor sleep will show up in your legs the next morning |
| Race-day awareness | Stay alert to your surroundings — traffic, other runners, aid station volunteers | Wear headphones outdoors; they block out the hazards you need to hear, from bikes to traffic |
Don't forget to hydrate early and often, especially on your long runs.
A few of these deserve a second look. Pain is the one runners most often talk themselves out of respecting — post-run soreness is normal, but pain that gets worse during the run is your body telling you something is wrong, and pushing through it is how a manageable niggle turns into weeks off. The same logic applies to pacing: starting conservatively costs you almost nothing if you feel great at mile 10, but starting too fast can turn your last 5K into a walk.
Frequently Asked Questions
How should you prepare for a half marathon?
Prepare by making sure you are well trained before race day rather than deciding to run on a whim. It helps to complete a shorter race, such as a five or ten kilometer event, before attempting the half marathon. Lay out your gear a few days early so everything is in place, and take a gentle run the day before to relieve tension and ready your body for the big race.
What should you eat before a half marathon?
Eat a balanced meal before the race so your body has the energy it needs, including proteins, carbohydrates, and some fat. Avoid greasy foods and sugars, which can affect how you feel during the run. Timing matters too, so avoid eating in the one to two hours right before the start, giving your body time to digest and helping you avoid stomach cramps or feeling sluggish.
Should you start a half marathon fast?
No. In the excitement of the start, many runners charge off too fast and regret it later. Remember that your aim is to finish the race, not to compete for first place, so start at a controlled pace. If you set off too fast you are likely to tire more quickly, and if you ever feel you are running at an uncomfortable pace, slow down.
Should you wear headphones during a half marathon?
No. Avoid wearing headphones whether you are training or racing outdoors. They tune you out from your environment and leave you vulnerable to hazards such as bikes, dogs, cars, and even criminals. Save your music player for the gym, where it is safer to block out your surroundings, and stay alert to what is happening around you during outdoor runs and races.
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