Lauren HollandBy Lauren Holland

Updated November 2026

Marathon advice for first timers comes down to three things: train consistently for at least 16 to 20 weeks, run most of your miles at an easy pace, and practice your fueling and gear before race day. Most first-time finishers fail because they start too fast, skip long runs, or try something new on the course. Fix those three habits and you give yourself a strong shot at crossing the line upright.

Why First-Timers Struggle

The distance itself is the main challenge, but the most common mistakes are avoidable. New marathoners often run their easy days too hard, which leaves them tired and under-recovered for key workouts. They also underestimate how long their long runs need to be. Many plans peak with a run of 18 to 22 miles, and skipping that run is one of the most frequent reasons people hit the wall at mile 20.

Shopping for one? See our guide: First Ever Marathon Time: 3 Best Guides and Pace Tools for First-Timers.

The Factors That Matter Most

Three areas make the biggest difference for a first marathon. The first is weekly mileage. Most beginner plans build to somewhere between 30 and 45 miles per week, though your starting point matters more than any single target. The second is pacing. Your goal pace should feel controlled in the first half, and you should be able to talk in full sentences on most training runs. The third is fueling. Your body can only absorb so many carbohydrates per hour, so you need to train your gut as well as your legs. For a deeper look at building the right schedule, see Marathon Training Plan for First Timers: A Step-by-Step Guide.

What to Do About It

Start by choosing a race about four to five months out, then pick a plan that matches your current weekly mileage. Build gradually and keep the increases modest. A common rule is to avoid raising weekly distance by more than about 10 percent per week. Use these steps to stay on track:

  1. Run three to five days per week, with at least one rest or cross-training day.
  2. Keep roughly 80 percent of your runs at an easy, conversational effort.
  3. Complete one long run per week, building to 18 to 20 miles at least three weeks before race day.
  4. Practice your race-day breakfast and gels on at least two long runs.
  5. Taper for two to three weeks, cutting volume while keeping a few short, sharp efforts.
  6. Run your race-day shoes and clothing for at least 30 miles before the event.
  7. Plan a conservative first half, then decide whether to push in the final 10K.

If you want a broader checklist, Marathon Running Tips for First Timers: A Step-by-Step Guide covers many of these points in more detail. Pacing, in particular, is worth studying before you line up, and Good Marathon Time for First Timer? Realistic Goals by Pace can help you set a target that fits your current fitness.

What We’d Use

A reliable running watch helps you hold easy pace on training days and avoid racing the early miles. Look for a GPS model with a pace alert feature. View on Amazon

Gels or chews make fueling simpler on long runs and race day, and many runners stick with the brand they tested in training. View on Amazon

FAQ

How long should I train for my first marathon?

Most first-time plans run 16 to 20 weeks. Shorter plans can work if you already run regularly, but starting with a solid base makes the process safer and more enjoyable.

Should I run every day?

No. Three to five running days per week is enough for most beginners. Rest days allow your muscles, tendons, and joints to adapt. If you have pain or injury concerns, consult a doctor or physical therapist before increasing your mileage.

Is it okay to walk during a marathon?

Yes. Many first-timers use planned walk breaks, such as one minute of walking every few miles, to finish strong and reduce fatigue. Walking is a legitimate strategy and does not disqualify you.

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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.