From 13.1 to 26.2: A Half Marathon to Marathon Training Plan

SuuntoRunJuly 17 2025

If you’ve conquered 13.1 miles, you’re already halfway to doing something extraordinary. Transitioning from a half-marathon to marathon training plan might sound daunting initially, but it’s a natural next step for runners who are ready to challenge their limits. With the right mindset, strategy, and tools, turning your training from a half-marathon to a marathon plan is a victory that is absolutely within reach.

1) Can I run a marathon if I can run a half-marathon?

Yes. The leap from a half-marathon to a marathon plan is rather significant and recommendable. The journey from half marathon to full marathon plan is much shorter than it seems, especially with a solid half marathon to marathon training plan. But your current fitness can impact. Prepare your body and mind for handling serious training volume now!

2) How long does it take from half-marathon to marathon training?

A typical half-marathon to marathon training plan spans around 12-18 weeks, based on your current mileage as well as goals.

Typical Half-Marathon to Marathon Training Timeline:

12 weeks are ideal for runners who’ve kept up consistent running and long runs around 8-10 miles post-race.

14-16 weeks are great for those returning from a break or even looking to gradually increase mileage.

18 weeks or more are recommended for runners with lower base mileage or even aiming for performance like time goals.

3) How do you convert from half-marathon to marathon training plan?

Many structured programs like Jack Daniel’s formula or even Hal Higdon’s training are specifically designed for runners.

Long runs get longer as you build up from 10-12 miles and transition to 18-20 miles on peak weeks.

Mileage volume increases gradually as weekly distance goes from approximately 25 miles to 35 and even 45 miles.

half marathon to marathon training plan

Leaping ½ marathon to marathon training plan may sound intimidating, but if you already have a half marathon experience, a well-designed half-marathon to marathon training plan is all about strategic adjustments. Here are some more tips below.

Increase Your Long Run Gradually

While you’ve likely capped your longest run at 10-12 miles during half-marathon training, marathon prep will require you to stretch that to 18-20 miles over time.

· Add 1-2 miles per week to your long run, maxing out at 20 miles about 3-4 weeks before the race.

· Every 3rd or 4th week, dial back the mileage to allow for recovery, called a cutback week.

Prioritize Recovery Like a Pro

Recovery is where gains are made, not just in training volume. A successful half-marathon to marathon training plan always includes rest.

· Take at least one full rest day per week.

· Use active recovery like walking, light cycling, or even yoga on cross-training days.

Add Strength Training to Support Distance Running

Running alone isn’t enough, as your hamstrings, hips, core, and glutes are your running system. Strength training helps prevent injury as well as improve endurance.

· Twice a week, 20-30 minutes for each session

· Focus on compound exercises like deadlifts, lunges, planks, glute bridges, or even calf raises

4) Half-marathon to marathon training plan

I have an 18-week half-marathon to marathon training plan. It’s built for beginner and intermediate runners who have recently completed a half marathon and are now ready to take on the challenge of a full marathon. If you want to train for a shorter period, you can check out the 16-week marathon training plan, or adjust your training schedule based on the following schedule:

Weeks 1-8: Foundation and Half Marathon to Marathon Plan Milestone

Week

Mon

Tue

Wed

Thu

Fri

Sat (Long Run)

Sun (Cross Training)

1

Rest

3 miles

3 miles

3 miles

Rest

6 miles

45-min cycling or walk

2

Rest

3 miles

3 miles

3 miles

Rest

7 miles

1-hour yoga or swim

3

Rest

3 miles

4 miles

3 miles

Rest

8 miles

45-min brisk walk

4

Rest

3 miles

4 miles

3 miles

Rest

9 miles

1-hour cross workout

5

Rest

4 miles

4 miles

3 miles

Rest

10 miles

1-hour low-impact cardio

6

Rest

4 miles

5 miles

3 miles

Rest

7 miles

 (cutback)

45-min easy cycling

7

Rest

4 miles

6 miles

4 miles

Rest

11 miles

1-hour swim

8

Rest

3 miles

3 miles

3 miles

Rest

Half marathon 

Recovery walk

 

Week 9-15: Mileage Peak and Half Marathon to Marathon Training

Week

Mon

Tue

Wed

Thu

Fri

Sat (Long Run)

Sun (Cross Training)

9

Rest

4 miles

5 miles

4 miles

Rest

10 miles

1-hour cross activity

10

Rest

4 miles

6 miles

4 miles

Rest

12 miles

1-hour yoga/ stretching

11

Rest

5 miles

7 miles

5 miles

Rest

16 miles

1-hour easy swim

12

Rest

4 miles

5 miles

5 miles

Rest

12 miles (stepback)

1-hour bike ride

13

Rest

5 miles

8 miles

5 miles

Rest

18 miles

1-hour slow hike

14

Rest

5 miles

5 miles

5 miles

Rest

14 miles

1-hour light cardio

15

Rest

5 miles

9 miles

5 miles

Rest

20 miles

1-Hour

recovery stretch

 

Week 16-18: Race Day of Your Half Marathon to Marathon Plan

Week

Mon

Tue

Wed

Thu

Fri

Sat (Long Run)

Sun (Cross Training)

16

Rest

4 miles

Rest

4 miles

Rest

12 miles

1-hour recovery walk

17

Rest

3 miles

Rest

3 miles

Rest

8 miles

45-min walk

18

Rest

2 miles

Rest

2 miles

Rest

Marathon

Rest


Suunto Run: A professional watch to marathon

For runners following a structured half-marathon to marathon training schedule, having a tool that not only tracks your pace but also analyzes your recovery and supports long efforts with real-time feedback is essential. The Suunto Run GPS watch was built with endurance athletes in mind. It’s more than a tracker, but a performance partner.

Suunto Run lime

What Real Runners Say

Here’s what real runners from Reddit’s communities are saying after using Suunto Run. 

● The watch is lightweight and comfortable to wear. The GPS accuracy is excellent, the best of any watch I’ve ever owned. Sevenslipperyseals

● This is my first Suunto watch, and all I have to say is it’s amazing. Toronto1976reddit

● For $250, the Suunto Run seems like a great deal with its AMOLED display and GPS. I think it’s worth considering. matt_legrand

What can Suunto Run do for Half Marathon to Marathon Training Progression

  • Real-time Half Marathon to Marathon Training Plan Feedback: Race time predictions for 5K, 10K, Half and Full Marathon, based on your VO2 max and past run performance.
  • Intelligent Recovery Scoring for Your Half-Marathon to Marathon Training Schedule: After each run, Suunto Run evaluates your Training Stress Score (TSS) and Recovery Time. You can use this to plan easier days and avoid overtraining.
  • Pro-Level Tuning from Metrics for Your Half-Marathon to Marathon Training Plan: Running Power measured from the wrist. Vertical oscillation and Ground Contact Time. Cadence and stride length. Posture Monitoring.
  • Battery Life Built for Race Day: Fully charged within 60 minutes. 20+ hours of GPS recording in full performance mode. Up to 8 days in regular training mode.

 

Running a marathon is more than just logging miles. It’s about leveling up. Even if it’s a half-marathon-to-marathon-in-12-weeks strategy or transitioning to a half-marathon-to-marathon training schedule, your journey depends on a strong plan. From structured weekly schedules to advanced tech like the Suunto Run, everything you need is within reach.

So, lace up, plan smart, and go the full distance of your half-marathon to full-marathon training plan. Because your next finish line isn’t the end, it’s the start of what you’re truly capable of.

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