Half Marathon Speed Builder

Workout - Half Marathon Speed Builder

• 10min @ 6'00''/km
• 6 lots of:
  • 400m @ 4'55''/km
  • 1min 30s rest
• 10min @ 6'00''/km

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Intro

The 12 Week Half Marathon Training Plan from This Messy Happy gets a full breakdown here, so you can jump into the workout whenever you’re ready. The complete video has additional context worth watching for the full picture.

Key points

• Aimed at recreational runners with a baseline of running 5 km a few times weekly, this plan builds to a half-marathon over three months.
• The weekly structure includes three runs (expanding to four later), a Monday strength-and-conditioning block, and planned recovery weeks that help prevent overtraining injuries.
• Three distinct phases organize your training:
  1. Base block: gradually work up to 7-10 km easy runs.
  2. Interval block: incorporate brief speed bursts while maintaining moderate volume.
  3. Peak block: maintain two steady runs and ramp up the long weekend run. The final week pulls back.
• Essential habits: stretch after each session, complete the strength-conditioning work every Monday, honor your rest days and recovery weeks, and avoid skipping consecutive workouts.

Workout example

Weeks 1-4 (Base Block)
- Monday: Strength & conditioning (body-weight circuit)
- Tuesday: Easy run 5-7 km (easy pace)
- Wednesday: Rest or cross-train
- Thursday: Easy run 5-7 km
- Friday: Rest
- Saturday: Long run starting 7 km, add 1 km each week up to ~10 km
- Sunday: Rest or light activity

Weeks 5-8 (Interval Block) – same structure, but replace the Tuesday run with a short interval session (e.g., 6 × 400 m at 5-10 s faster than goal pace with 90 s jog recovery). Keep the weekend long run building to 12-14 km.

Weeks 9-12 (Peak & Taper) – keep two steady runs (5-8 km) and a longer weekend run that peaks at 18-20 km in week 11, then drop back 20-30% in week 12 for a fresh race day.

Closing note

Take this plan and make it yours by adjusting paces in the Pacing app to match where you are now.

References

• 12 Week half marathon training plan - YouTube (YouTube Video)