Sub-4-Hour Marathon: How to Train, What Pace to Run and Which Races to Choose in 2027
Running a marathon in under four hours is one of the most popular goals among recreational runners. It’s an ambitious target, but one that’s achievable for runners with a solid endurance base and a commitment to consistent training.
The challenge sounds simple: complete 42.195 km before the clock reaches four hours.
But anyone who has run a marathon knows that the final kilometres can change everything.
A pace that feels comfortable at 15 km can become a serious challenge at 35 km. That’s where preparation, strategy and the ability to manage your effort make all the difference.
If you’re planning to run a marathon in 2027 and want to finally break the four-hour barrier, this guide covers what it takes, how to structure your training and which races in Portugal can help you prepare.
What Pace Do You Need to Run a Marathon in Under 4 Hours?
To complete 42.195 km in four hours, you need to maintain an average pace of approximately 5:41 min/km (9:09 min/mile).
That might sound manageable for runners who already complete 10K races or half marathons regularly.
However, the real challenge isn’t running at that pace for a few kilometres. It’s maintaining it for almost an entire morning.
For reference, here’s what your approximate split times would look like at a consistent pace of 5:40 min/km:
| Distance | Cumulative Time |
|---|---|
| 5 km | 28:20 |
| 10 km | 56:40 |
| 21.1 km | 1:59:34 |
| 30 km | 2:50:00 |
| 40 km | 3:46:40 |
| 42.195 km | 3:59:06 |
This strategy leaves a small margin to finish under four hours, but remember that aid stations, weather conditions, elevation and fatigue can all affect your performance.
That’s why preparing for a sub-4-hour marathon involves much more than simply practising a 5:40 min/km pace.
How Do You Know If You’re Ready for a Sub-4-Hour Marathon?
Before committing to this goal, it’s worth assessing your current fitness.
According to Performance Running, completing a half marathon in approximately 1:50–1:55 or running 10 km in around 50–53 minutes can provide an initial indication of whether a sub-4-hour marathon is realistic.
These results don’t guarantee success, but they can help determine whether you already have the speed required for your goal.
Endurance is equally important.
If you can run a fast 10K but struggle to complete 20 km comfortably, you’ll probably need to dedicate more time to building your aerobic endurance.
On the other hand, if you’ve already completed a marathon close to four hours, small adjustments to your training, nutrition and pacing strategy might make a significant difference.
The key is to establish a goal that matches your experience rather than trying to rush the process.
A 16-Week Marathon Training Plan Can Make the Difference
Performance Running has developed a comprehensive Sub-4-Hour Marathon Training Plan, written by Rui Cardoso, outlining a structured approach for runners aiming to break the four-hour barrier.
The guide organises training over 16 weeks, combining easy runs, higher-intensity sessions, long runs, strength training and recovery periods.
The central principle is simple: you don’t need to run fast in every training session to become a faster marathon runner.
In fact, a significant proportion of your training should be completed at an easy intensity, allowing you to build endurance without accumulating excessive fatigue.
The Four Phases of Marathon Preparation
1. Building Your Aerobic Base
During the first few weeks, the focus should be on developing endurance, establishing consistency and gradually increasing your running volume.
This is also a good time to introduce or maintain a strength training routine.
2. Developing Endurance
As training progresses, long runs gradually become longer and more specific sessions are introduced.
During this phase, your body adapts to sustaining effort over extended periods.
3. Marathon-Specific Preparation
The most demanding weeks include long runs that may reach 30–32 km, sometimes incorporating sections close to your intended marathon pace.
These sessions are particularly valuable for testing your pacing strategy, nutrition and race-day equipment.
4. Tapering Before Race Day
During the final two to three weeks, training volume is gradually reduced to allow your body to recover while maintaining the fitness developed throughout the programme.
This phase, known as the taper, is essential for arriving at the starting line feeling rested and prepared.
Training volume and intensity should always be adapted to your experience, availability and recovery capacity.
For a detailed breakdown of training sessions, recommended paces and weekly structure, explore the complete Sub-4-Hour Marathon Training Plan by Performance Running.
Three Common Mistakes That Could Ruin Your Sub-4-Hour Marathon
Even with a well-structured training plan, certain mistakes can make achieving your goal significantly harder.
1. Running Too Fast on Easy Days
It’s tempting to complete every training session close to your target marathon pace.
However, easy runs serve an important purpose: developing aerobic fitness while allowing your body to recover.
Turning every session into a hard workout can leave you feeling exhausted before your long runs and make consistent training more difficult.
2. Ignoring Your Race-Day Nutrition Strategy
A four-hour marathon requires a proper fuelling strategy.
During prolonged exercise, your body relies heavily on its energy reserves, and consuming carbohydrates during the race can help maintain performance.
The Performance Running guide discusses strategies involving approximately 60–90 grams of carbohydrates per hour, depending on individual tolerance and how well the digestive system has been trained.
Don’t wait until race day to experiment with new energy gels or sports drinks.
Use your long runs to discover what works best for you, and consider consulting a sports nutritionist for personalised advice.
3. Starting the Marathon Too Fast
The first few kilometres of a marathon can feel surprisingly easy.
Adrenaline, crowds and the excitement of the starting line often make runners go faster than planned.
But gaining a few seconds during the first 10 km can cost several minutes later in the race.
For runners targeting a sub-4-hour finish, discipline at the beginning is often more valuable than an aggressive start.
Which Races in Portugal Can Help You Prepare for a Sub-4-Hour Marathon?
Good marathon preparation doesn’t happen exclusively during training sessions.
Participating in shorter races can help you assess your fitness, practise race-day nutrition, gain experience in competitive environments and understand how your body responds to sustained effort.
If you’re preparing for a spring marathon in 2027, here are some events available through RaceFinder that could fit into your training schedule.
1. Meia Maratona Évora — Test Your Endurance
22 November 2026 | Évora, Portugal
The Meia Maratona Évora offers an opportunity to assess your fitness before entering the more specific stages of marathon preparation.
The event includes two competitive distances: 21.1 km and 10 km.
For runners targeting a sub-4-hour marathon, the half marathon is particularly useful because it provides a chance to test your ability to maintain a steady effort over a significant distance.
If you’re already finishing half marathons around 1:50–1:55, you can use your performance as one reference when determining your training paces.
If you’re not quite there yet, the race can still help identify which areas of your fitness need more attention.
Explore the race and register on RaceFinder
2. Maratona do Algarve — Choose Between 10K, Half Marathon and Marathon
6 December 2026 | Vilamoura, Algarve
The Maratona do Algarve 2026 offers several distances, including a full marathon, half marathon and 10K.
For runners preparing for a marathon in 2027, the half marathon can serve as an intermediate endurance test.
The 10K distance is also useful for assessing your current speed and determining whether your training paces are appropriate for your goal.
The full marathon is an option for runners who have already completed the necessary preparation and are ready to tackle 42.195 km.
If your main goal is a spring 2027 marathon, however, there’s no need to rush into racing the full distance.
Explore the race and register on RaceFinder
3. São Silvestre da Batalha — A Speed Test Before 2027
12 December 2026 | Batalha, Leiria
10K races are excellent opportunities to monitor your progress throughout marathon preparation.
The 13th São Silvestre da Batalha is an option for runners looking to finish 2026 with a competitive challenge.
The distance allows you to test your ability to sustain faster paces and collect useful information for planning the next stages of your training.
However, you don’t need to race every event at maximum intensity.
Depending on your training phase, a competition can also be used as a controlled workout.
What matters most is ensuring that each race has a clear purpose within your overall training plan.
Explore the race and register on RaceFinder
4. Lisbon Eco Marathon 2027 — A Spring Marathon Challenge
11 April 2027 | Lisbon, Portugal
If you’re planning to run a marathon in spring 2027, the Lisbon Eco Marathon is one of the events available for registration through RaceFinder.
The race takes place in Lisbon, with routes through the Monsanto Forest Park area and the start and finish near Parque Eduardo VII.
The event offers several distances, including a marathon, half marathon, mini marathon and walk.
Its April date allows runners to structure a 16-week training programme over the winter, provided they already have an appropriate fitness base.
However, there’s an important factor to consider: the course through Monsanto has different characteristics from flatter urban marathons.
If your primary goal is finishing under four hours, you should carefully examine the elevation profile, terrain and officially measured course distance before deciding on your pacing strategy.
A marathon with significant climbs or more demanding terrain can make a sub-4-hour finish considerably harder, even for runners capable of maintaining the necessary pace on flat roads.
Nevertheless, it can be an excellent choice for those who want to combine a marathon challenge with a different running experience in Lisbon.
Explore the race and register on RaceFinder
How to Choose the Best Marathon for a Personal Best
If your goal is to finish a marathon in under four hours, choosing the right race can be almost as important as choosing the right training plan.
Before registering, consider the following factors.
Elevation profile: Flatter courses with fewer significant climbs generally make it easier to maintain a consistent pace.
Weather conditions: High temperatures, strong winds or heavy rain can make achieving your target more difficult.
Aid stations: Check where hydration stations are located and which products will be available during the race.
Race date: Make sure you have enough time to complete your training programme, including recovery weeks.
Course certification: If you’re targeting an official personal best over 42.195 km, verify that the course is accurately measured and meets the relevant certification requirements.
Logistics: Long journeys, changes to your routine and poor sleep before race day can all affect your performance.
The most famous marathon isn’t always the best choice for your personal goal.
The important thing is finding an event that matches your preparation, experience and priorities.
So, Is Running a Marathon in Under 4 Hours Really Possible?
Absolutely. But the journey towards that goal begins long before race day.
It requires weeks of consistency, patience during easy runs, discipline throughout your long runs and the ability to adapt your preparation to your body’s needs.
And there’s something important to remember: finishing a marathon in 4:05, 4:30 or 5:00 is still an incredible achievement.
Breaking four hours is an exciting goal, not a measure of your worth as a runner.
If you’re ready to take on the challenge, start by building a realistic training plan, explore the resources available from Performance Running, and choose races that will help you arrive at the starting line feeling prepared and confident.
On RaceFinder, you can discover 10K races, half marathons and marathons across Portugal, compare events and find opportunities to put your training to the test.
Your next marathon starts long before the starting line.
And perhaps 2027 will be the year you finally see the clock stop before four hours.
