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GA Endurance | Marathon Intermediate | 12 Weeks | Base | Coach Access

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GA Endurance | Marathon Intermediate | 12 Weeks | Base | Coach Access

Includes Structured Workouts

Structured Workouts automatically sync with compatible devices and guide you through workouts in real time.


Learn More about Structured Workouts.

Author

GA Coaching

All plans by this Coach

Length

12 Weeks

Includes Structured Workouts

Structured Workouts automatically sync with compatible devices and guide you through workouts in real time.


Learn More about Structured Workouts.

Plan Description

Is This Plan For You?

This 12-week Marathon Intermediate Base plan by GA Endurance is designed for runners who are already training consistently and want to establish a solid aerobic foundation before entering a more performance-focused marathon training block.

It is ideal for athletes who have an existing endurance base but need a structured phase to improve consistency, durability, and movement efficiency in a relatively shorter timeframe.

If you are looking for a focused, efficient base phase that prepares your body for higher training loads and structured intensity, this plan provides a clear, progressive pathway.


What You Can Expect

• A complete 12-week structured Base progression for Marathon Intermediate athletes

• Shorter base phase with controlled and progressive load increase

• Strong emphasis on aerobic development and consistency

• Progressive long runs to build endurance and fatigue resistance

• Predominantly easy and steady-state running with minimal structured intensity

• Light tempo and neuromuscular work introduced earlier compared to longer base plans

• Strategically placed recovery weeks to support adaptation and reduce injury risk

• Focus on pacing discipline, efficiency, and movement quality

• Clear, easy-to-follow workouts using pace, heart rate, or perceived effort

• Optional strength guidance to support durability and injury prevention


Coaching & Support

This plan includes Coach Access.

If you have any questions during your training, you can reach out anytime via:

coachsupport@gaendurance.com


Requirements

To start this plan, you should be able to:

• Run continuously for at least 12–16 km

• Train consistently 3–4 times per week

• Have a basic aerobic foundation and recent running experience

• Be ready to follow a structured and progressive base phase

A GPS watch and heart rate monitor are recommended for best results.


Final Note

This 12-week intermediate base plan is built to efficiently prepare you for the demands of marathon training within a shorter timeframe.

With reduced base duration, consistency and execution quality become even more important. If followed with discipline, this plan will help you build aerobic capacity, improve durability, and transition smoothly into more advanced marathon training phases.

Explore more training plans at GA Endurance

How it Works

Load Your Plan

Quickly view upcoming workouts in the TrainingPeaks app.

Workout and Analyze

Upload completed workouts from your favorite tracking app or device.

Track Your Progress

Get feedback, stay on top of your training and perform at your best.

Learn More

Training Plan Sample Week

Stats

Average Weekly Breakdown

Workouts Weekly Average Longest Workout
Run x5
04:21:00 02:00:00
Day Off x2
—— ——
Workouts Per Week Weekly Average Longest Workout
Run
04:21:00 02:00:00
Day Off
—— ——

Training Load By Week


This plan works best with the following fitness devices:

  • Heart Rate Monitor

All supported devices

GA Endurance

GA Coaching & Sports Science

Goksen Cinar, MSc, and Ozgur Axaman, combining decades of coaching experience with applied sports science. Both are multiple-time Ironman 70.3 World Championship qualifiers, with extensive full-distance Ironman experience. Their system integrates structured training, data-driven methodology, and real-world coaching to help athletes train with clarity, consistency, and long-term performance focus.


  • This plan includes a Free Basic TrainingPeaks Account.
  • Access your training plan anywhere on the TrainingPeaks mobile and desktop apps.
  • Track your performance with robust data tracking and detailed graphs.
  • Plan for your event in the TrainingPeaks calendar.
  • Track your weight, sleep, hours, fatigue and stress while you train.
  • Completed workouts sync with popular apps like Garmin and Wahoo. Learn More
  • If plan includes Structured Workouts, then planned workouts sync to compatible devices and guide you through workouts in real time. Learn More

Refund Policy

This plan is protected by our Refund Policy and may, with the author's approval, be exchanged for a plan of equal value from the same author.

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