Lauren HollandBy Lauren Holland

Updated November 2026

To run your first half marathon, you need about 12 weeks of consistent training, a base of roughly 15 to 20 miles per week before you start, a long run that builds to 10 to 12 miles, and a plan for pacing, fueling and recovery. Most first-timers finish comfortably when they run the first 10 miles at a conversational effort and save their harder efforts for the final stretch. The steps below cover how to get there safely.

Why a Structured Plan Matters for Your First Half Marathon

Most people who struggle at 13.1 miles don’t lack fitness. They ramp up mileage too fast, skip recovery, or start the race too quickly. A structured plan spreads the stress across weeks so your muscles, tendons and bones can adapt. Common guidance is to increase weekly mileage by no more than about 10 percent, and to include a down week every third or fourth week. If you’re just starting out, a plan that runs three to four days per week with one long run and two shorter easy runs is a reliable template.

Shopping for one? See our guide: 3 Best Run Your First Half Marathon Training Programs (2026): Our Picks.

Before committing to a plan, get a quick check with your doctor if you have heart, joint or metabolic concerns, or if you’ve been inactive for a long time. This is general guidance, so consult a professional who knows your health history.

The Key Factors That Shape Your Training

Four variables determine whether your first half marathon goes well: your starting mileage, your long-run progression, your effort level on easy days, and your recovery habits.

  • Starting base. If you can comfortably run 15 to 20 miles per week, you can start a 12-week plan. If you’re at 5 to 10 miles, consider a 16-week plan instead.
  • Long-run progression. Your longest run should build gradually, usually peaking at 10 to 12 miles about two to three weeks before race day. Reviewing how to structure your half marathon long runs can help you space them correctly.
  • Easy-day effort. Most training miles should feel easy enough to hold a conversation. Running too hard on easy days is the most common mistake beginners make.
  • Recovery. Sleep, hydration, and a rest day or two each week matter as much as the runs themselves.

How to Pace Your First Race Day

Your goal on race day is to finish strong, not to hit a specific split from the start. Run the first mile about 30 to 60 seconds per mile slower than your goal pace. Many beginners start too fast because of adrenaline and crowd energy, then fade badly after mile 8. If you’re unsure of your goal pace, use a recent 5K or 10K result and a race-time calculator to estimate it. Knowing what a typical finish looks like can also help set expectations, which is covered in our guide on the average first half marathon time beginners run.

What to Do About Fueling and Hydration

For runs over 90 minutes, you’ll want to take in carbohydrates. Most sports nutrition guidance suggests about 30 to 60 grams of carbohydrate per hour for efforts of this length. Practice your fueling during long training runs so you know how your stomach handles it. Nothing new should appear on race day. Energy gels are a common option, and if you’re deciding when to use them, our step-by-step timing guide walks through the process. Electrolytes and water should be consumed based on thirst and sweat rate, not a fixed schedule.

Practical Steps to Follow

  1. Choose a race date 12 to 16 weeks out and pick a plan that matches your current mileage.
  2. Run three to four days per week, with one long run on the weekend.
  3. Keep at least 80 percent of your running at an easy, conversational effort.
  4. Add one strength session per week, focusing on legs and core, for 20 to 30 minutes.
  5. Practice race-day fueling and wear your race-day shoes and clothing on at least two long runs.
  6. Taper for the final one to two weeks, reducing volume while keeping a few short efforts. For details, see our half marathon taper week guide.
  7. Arrive early on race day, warm up for 10 minutes, and start at the pace you planned, not the crowd’s pace.

What We’d Use

A well-fitted pair of running shoes is the single most useful purchase for a new half marathoner, since it affects comfort over long distances more than almost any other item.

  • Brooks Ghost 16: A neutral daily trainer that many beginners find forgiving over long distances. View on Amazon
  • Garmin Forerunner 265: A GPS watch that helps you monitor pace and heart rate on training runs. View on Amazon

How many weeks do I need to train for a first half marathon?

Most beginners train for 12 to 16 weeks. A longer plan helps if you’re starting from a low base of fewer than 10 miles per week.

Can I walk during a half marathon?

Yes. Walk breaks are a legitimate strategy, and many runners use a run-walk ratio such as 4 minutes running and 1 minute walking. Practice it in training so it feels natural on race day.

Do I need to run every day?

No. Three to four running days per week is enough for most first-time half marathoners, with rest or cross-training on the other days.

What should I eat the night before?

Choose familiar, carbohydrate-rich foods that sit well with you, such as pasta or rice with a small amount of protein and low fat. Avoid trying new foods.

Is it normal to feel tired after a long run?

Yes, fatigue after long runs is expected. Persistent fatigue, sharp joint pain, or unusual symptoms should be checked by a medical professional.

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Lauren Holland

About Lauren Holland

Lauren Holland is part of our editorial team and reviews and edits our marathon & half-marathon guides, checking product details against manufacturer specifications and owner feedback.