Marathon training plan: how to prepare for your first marathon

How long does it take to prepare for a first marathon?

It depends on where you start. If you already run a few days a week and can comfortably handle a longer run, the common advice is four to five months of marathon-specific preparation. If you are not running regularly yet, build a base first, which adds a few more months. Count back from race day and leave a few weeks of margin for illness, work or travel.

The base is the ground the plan stands on: running a few days a week, mostly easy, without interruption. Consistency matters more than speed here. Muscles, tendons and joints adapt to running load more slowly than the heart and lungs, which is why people who skip the base and jump into long runs so often get hurt. Patience now pays for everything later.

A half marathon is a useful stepping stone. Training for one teaches you the long-run habit, a race-morning routine and pacing discipline at low risk, and your result is one of the most reliable guides to a realistic marathon time. Racing a half a few months before your first marathon tests your preparation and keeps your goal honest.

How should a marathon training week be structured?

A good marathon week is simple. Most of your running is easy: you can talk and your breathing stays under control. One long run a week is the main source of endurance. One quality session adds a harder stimulus, such as a tempo run, threshold intervals or, later on, sections at goal marathon pace. The other days can be rest, strength work or another sport.

With four running days, a workable layout is two easy runs and one quality session during the week, with the long run at the weekend. Keep at least one easy day or rest day between the quality session and the long run. If you only have three running days, drop one easy run and keep the long run and the quality session.

• Easy runs: most of the week, at conversational pace.
• Long run: once a week, steady and controlled.
• Quality session: once a week, tempo, threshold or race pace.
• Strength: short and regular, especially for hips, calves and core.
• Rest: at least one day, not up for negotiation.

How should the long run progress?

The long run grows gradually over a few weeks, then a lighter week with a shorter long run lets your body recover. Most of it is run at an easy pace; the point is getting used to time on your feet, not speed. Later in the preparation, short sections at goal pace near the end of the long run teach you to hold pace while tired.

Most first-time marathoners never run the full 42 km in training; the longest run usually stays well short of it. On race day, the freshness from the taper and the race atmosphere carry you over the extra distance. Running the full distance in training takes days to recover from and can disrupt the following weeks. The longest run is there to build endurance safely, not to prove the distance.

The long run is also where you rehearse race-day fuelling and drinking. Whatever you plan to take in the race, which gel, which drink and how often, try it on long runs and learn what your stomach tolerates. Exact needs vary from person to person; if you have a specific health condition, ask a professional. The rule is simple: nothing new on race day.

How do you set a realistic goal time?

In a first marathon, the smartest goal is to finish feeling good. If you want a time goal, base it on evidence rather than hope: a recent half marathon or 10K result is a far better guide than your training paces. Marathon pace is clearly slower than shorter race pace, and simply doubling a shorter race time to set a target is a classic mistake.

Test your goal pace in the race-pace sections of your long runs. If it still feels hard late in your preparation, the goal is too ambitious. On race day, run the first half slightly more cautiously than planned to leave room in the second. Energy spent early never comes back: seconds gained in the first kilometres can become minutes lost in the last. A patient start is the cheapest insurance.

The taper and race day

The taper is the reduction in training volume over the final weeks before the race, usually lasting one to three weeks. It sheds accumulated fatigue while keeping the fitness you built. Volume drops but intensity does not vanish: short race-pace sections keep your legs sharp. Feeling sluggish or restless during the taper is normal; do not add training to make up for fitness you fear losing.

Race day should repeat a day you have already rehearsed: breakfast, shoes, kit and fuelling plan all tried on long runs. Arrive early, keep the warm-up short and light, and do not get swept along by the crowd at the start. Plan the aid stations, and when it gets hard in the second half, run by effort rather than by your goal. Afterwards, easy walks and rest are the best recovery.

The most common first-marathon mistakes

First-time marathoners make strikingly similar mistakes. Most come from doing too much, too fast or too soon, and some stay invisible until race day. The good news is that all of them are easy to avoid once you know them. Read this list at the start of your preparation and again as you go into the taper.

• Running easy days at a moderate pace, then arriving tired at the quality session.
• Lengthening the long run every week with no lighter weeks.
• Cramming missed workouts into the following days.
• Trying fuelling or shoes for the first time on race day.
• Picking a goal time from hope, then starting too fast.
• Training through pain that does not go away; if it persists, see a health professional.

Frequently asked questions