The Final 6 Weeks Before a Marathon: A Week-by-Week Countdown to Race Day

With the London Marathon now just six weeks away, many runners are entering the most important phase of their training.

The majority of the hard work is already done. Now the focus shifts toward marathon-specific workouts, practising your fuelling strategy, and tapering properly so you arrive fresh on race day.

This is simply my approach based on my own experience and the runners I coach. There are many ways to prepare for a marathon, but this structure has worked well for a lot of athletes targeting peak performance.

Let’s break it down week by week.

Week 6: A Half-Marathon Fitness Test

Around six weeks out from a marathon, I like to include a half-marathon race or controlled effort in the diary.

This isn’t necessarily an all-out race effort. Instead, think of it as a controlled effort at around 90% intensity.

A great way to structure this is:

• Start at marathon pace

• Gradually increase the effort

• Finish around half-marathon pace

Essentially, you’re aiming for a negative split.

I recently did this myself at the Cambridge Half Marathon, running 1:13:00, using it as a fitness check rather than a maximal effort.

At this stage of a marathon build, you are typically finishing the threshold-building phase of training before transitioning into the marathon-specific training block.

Week 5: Recovery or Transition Into Marathon-Specific Work

If you raced a half-marathon in week six, this is a good time to schedule a deload week.

A deload usually involves:

• Reducing training volume by around 50%

• Reducing training intensity

• Prioritising sleep, nutrition and recovery

This allows your body to absorb the training stimulus from the race.

If you didn’t race, this is the point where you begin the marathon-specific phase of training, which typically lasts 3–4 weeks before the taper begins.

Weeks 5–2: The Marathon Specific Training Block

This period is where your training becomes highly specific to marathon pace and marathon effort.

The majority of your running should still remain easy aerobic mileage, but the focus of key workouts shifts away from:

• Threshold sessions

• VO₂ max workouts

and toward longer marathon pace efforts.

The goal here is to build:

• Rhythm

• Efficiency

• Control at marathon pace

Some workouts I often use in long runs during this phase include:

Example Marathon Pace Long Run Sessions

1️⃣ 4 × 5 km @ Marathon Pace (1 km float recovery)

2️⃣ 3 × 8 km @ Marathon Pace (1 km float)

3️⃣ 2 × 10 km @ Marathon Pace + 5 km faster (1 km float)

4️⃣ 12 km easy + 16 km @ Marathon Pace + 3 km cool down

These sessions teach your body to hold marathon pace when fatigue starts to build, which is critical for race day.

How Long Should Your Long Runs Be?

During this marathon-specific phase many runners will also complete the longest long run of their marathon training plan.

For most runners this will fall somewhere between:

30–35 km (18–22 miles)

The goal of the long run isn’t simply distance. Instead it is about:

• Spending time on your feet

• Practising marathon pace under fatigue

• Dialling in your race fuelling strategy

This is often where the biggest confidence gains occur during a marathon build.

Practising Your Marathon Fuelling Strategy

One of the most important parts of the final training block is dialling in your marathon fuelling strategy.

During these marathon-specific long runs you should practise:

• Taking gels during runs

• Hydrating consistently

• Carbohydrate intake before long runs

• Recovery nutrition afterwards

I like to prepare the gut by increasing carbohydrate intake before long runs, then continuing with high carbohydrate intake afterwards to support recovery.

This helps your body become comfortable digesting carbohydrates while running, which is crucial during the marathon.

Peak Week: Around 3 Weeks Before Race Day

For many runners, peak mileage occurs around three weeks before the marathon.

This is usually the highest volume week of your training cycle.

During this week it becomes especially important to prioritise:

• Sleep

• Hydration

• Nutrition

• Recovery

You’re pushing your body close to its maximum training load, so small lifestyle factors can make a big difference.

This is also the point where small niggles can begin to appear.

As a physiotherapist, one of the most common mistakes I see is runners forcing sessions when something doesn’t feel right. Missing one workout is far better than losing several weeks of training due to injury.

Listening to your body during this phase is key.

Weeks 2–1: The Marathon Taper

Around two weeks before the marathon, I begin the taper.

A typical taper might look like:

• Week 2 out: Reduce training volume by around 40%

• Race week: Reduce volume by another 40%

The key idea is to keep runs short and purposeful, while still including small doses of marathon pace running.

Some sessions I like during the taper include:

Example Taper Workouts

1️⃣ 10 min easy

4 × 5 min @ Marathon Pace (2 min float)

10 min cool down

2️⃣ 10 min easy

15 min @ Marathon Pace

10 min easy

3️⃣ 10 min easy

6 × 600 m @ Marathon Pace

10 min cool down

The goal here is not to build fitness, but to maintain neuromuscular sharpness and race rhythm.

Why the Taper Is So Important

The purpose of the taper is to allow:

• Muscle tissues to recover

• Training adaptations to take place

• Energy stores to fully replenish

This is where supercompensation happens.

Your body is used to operating under high training loads, so when volume drops, it recovers quickly and becomes stronger.

Maranoia: The Strange Psychology of Tapering

During the taper many runners experience something often called “maranoia.”

This is when you start to feel:

• Sluggish

• Unfit

• Anxious about losing fitness

The reality is the opposite.

If the taper is done properly, you will arrive on the start line fitter than ever despite doing less training.

Trust the process.

Race Week: Keep Things Simple

During the final week before a marathon, the goal is to stay relaxed and avoid unnecessary stress.

A few simple principles can help:

• Avoid trying anything new with shoes, nutrition or equipment

• Reduce or remove heavy strength training

• Prioritise restful activities, sleep and hydration

• Finalise your race day logistics

Knowing your travel plan, start time, fuelling strategy and pacing plan in advance helps reduce unnecessary race-day nerves.

Race Pace Strategy

One of the most common mistakes runners make in the marathon is starting too fast.

The adrenaline and excitement on race day can make your goal pace feel very comfortable early on.

Instead, aim to:

• Run the first 5–10km slightly controlled

• Settle into your goal marathon pace

• Allow the race to come to you

Many successful marathon runners run their best races with slight negative splits.

Patience early on usually pays off later in the race.

The Final Carb Load Before the Marathon

In the 24–48 hours before race day, I recommend a structured carbohydrate load.

A common guideline supported by research is:

7–10 g of carbohydrates per kilogram of bodyweight

This might sound like a lot, but the goal is to maximise glycogen stores in the muscles and liver before the race.

In the final few days, it can also help to:

• Reduce dietary fat

• Reduce high-fibre foods

The goal isn’t to massively increase calories, but to optimise carbohydrate intake while keeping digestion comfortable.

The Final Goal: Arrive Fresh on the Start Line

By the time race week arrives, the goal is simple:

✔ Healthy

✔ Rested

✔ Fuelled

✔ Confident

If you’ve executed the final six weeks well, your fitness is already there.

The final phase of marathon training isn’t about building huge amounts of fitness — it’s about refining the work you’ve already done and arriving on the start line ready to perform.

Trust the process and enjoy the experience.

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