Are you planning to race a Spring marathon in 2026? It’s never too early to start thinking about your training structure! Based on the successful preparation frameworks of the past, here is your guide to ensuring you arrive at the start line fit, healthy, and ready to smash your goals.
Setting Your Targets
The spring marathon season of 2026 features some of the world’s most iconic races. A dedicated 12-week training plan is essential for success.
Here are the key marathon dates for Spring 2026 that many runners will be targeting:
– Rotterdam Marathon – Sunday, April 12, 2026
– Boston Marathon – Monday, April 20, 2026
– London Marathon – Sunday, April 26, 2026
– Limerick Marathon (Great Limerick Run) – Sunday, May 3, 2026
The 12-Week Intensive Plan
Your intensive training block will be 12 weeks long. To maximize your results, we recommend integrating two key tune-up races:
A 10km Race: Scheduled at the end of the 4th week of the 12-week block.
– For Rotterdam : 15/02/2026
– For Boston 22/02/2026
– For London 01/03/2026
– For Limerick 08/03/2026 (Kinvara for example)
A Half Marathon Race: Scheduled at the end of the 7th week of the 12-week block.
– For Rotterdam : 08/03/2026 (Kinvara for example)
– For Boston 15/03/2026 (Mullingar for Example)
– For London 22/03/2026
– For Limerick 29/03/2026
Pre-Training Build-Up: Consistency is Key (Late 2025/Early 2026)
It is crucial to enter the 12-week intensive block with a solid running foundation. For those aiming for a strong marathon finish, you should be running a minimum of 50 km per week (32 miles/week) with long runs lasting 1 hour 40 minutes to 1 hour 45 minutes at the start of the 12-week training period (mid-January 2026).
You are not there yet? Then use the preceding two to three months (November, December 2025, and early January 2026) to gradually increase your mileage. Increasing the mileage too fast is the leading cause of injury.
Here is an example of a gradual preparatory training plan leading up to your 12-week start:
| Week Rotterdam | Week Boston | Week London | Week Limerick | Minimum Weekly mileage | Long run duration |
| 48 | 49 | 50 | 51 | 35km / 21 miles | 1h00 |
| 49 | 50 | 51 | 52 | 37km / 23 miles | 1h05 |
| 50 | 51 | 52 | 01 | 40km / 25 miles | 1h10 |
| 51 | 52 | 01 | 02 | 30km / 19 miles | 1h00 |
| 52 | 01 | 02 | 03 | 40km / 25 miles | 1h20 |
| 01 | 02 | 03 | 04 | 44km / 27 miles | 1h30 |
| 02 | 03 | 04 | 05 | 48km / 30 miles | 1h40 |
| 03 | 04 | 05 | 06 | 50km / 32 miles | 1h45 |
Booking Your Race (Action Item)
Don’t wait until the last minute! Start to book your half marathon and 10km races now to ensure they are placed ideally before your target marathon (i.e., within Weeks 4 and 7 of your 12-week training plan).
Final Tips
Ensure you stay well hydrated, even during the cooler winter months, and maintain a healthy diet to fuel your increased training load. Consistency and patience in this preparatory phase will be the foundation of your success.
Looking forward to seeing you this spring at the start line of a Marathon!
Happy running!