Half Marathon Sub-2 Training: 8-Week Plan and Key Interval Workouts

Introduction

The half marathon (21.0975 km) is one of the most popular distances in modern road running—challenging enough to be meaningful, yet with a much shorter training cycle than the full marathon. Sub-2 (breaking 2 hours) is the most common first breakthrough goal for half-marathoners, requiring an average pace of 5:41 per kilometer—a target that, for many runners who have just completed a half marathon, can be achieved with just 8 weeks of focused training.

Who This Plan Is For

This 8-week plan suits runners who meet the following criteria:

• Current half-marathon time: between 2:05–2:15
• 5K test pace: approximately 28–32 minutes
• Consistent weekly mileage: 30–40 km
• Continuous running ability: can complete 15+ km without stopping

If your half-marathon time is above 2:20, it is recommended to first complete 4–6 weeks of base training (35–45K per week at an easy pace) before starting this plan.

8-Week Plan Overview

Week	Weekly Mileage	Long Run	Key Workout
Week 1	38K	16K	Tempo Run 5K
Week 2	42K	17K	1000m × 5 Intervals
Week 3	45K	18K	Tempo Run 7K
Week 4	38K (Recovery Week)	15K	Pace Run 3K
Week 5	48K	19K	1200m × 5 Intervals
Week 6	50K	20K	Tempo Run 8K
Week 7	45K	17K	Race Simulation 10K
Week 8	25K (Taper)	8K	Light Pace Run

Key Interval Workouts Explained

1000-Meter Intervals

1000-meter intervals are the gold-standard workout for improving VO₂ max. The recommended pace is about 30–35 seconds per kilometer faster than your half-marathon goal pace (i.e., approximately 5:05–5:10/km):

• Warm-up: 2 km easy run
• Main set: 1000m × 5 reps at 5:05–5:10 pace, with 90 seconds of easy jogging recovery between reps
• Cool-down: 1.5 km easy run

In weeks 5–6, increase the volume to 1200m × 5 reps while maintaining the same pace, raising the intensity.

Tempo Runs

Tempo runs are the core workout for building your lactate threshold. For a Sub-2 half marathon, the recommended tempo pace is 5:15–5:20/km:

• You should feel “comfortably hard”—able to speak in short sentences but not hold a full conversation
• Run continuously at tempo pace for 5–8 km, without adding jogging recoveries
• Schedule one tempo run in each of weeks 1–6, extending the distance by 1–2 km every two weeks

Sunday Long Run

The long run is the foundation for building your aerobic base and strengthening running endurance. The recommended pace is 60–90 seconds slower than your half-marathon goal pace (i.e., 7:00–7:15/km), with emphasis on time rather than speed. Starting from week 4, add the final 3 km of the long run at your 5:41 goal pace, allowing your body to become familiar with race-day effort early.

Sample Weekly Training Schedule

Using Week 3 as an example:

• Monday: Rest
• Tuesday: Easy run 10K (6:30/km)
• Wednesday: Tempo run workout — 2K warm-up + 7K tempo (5:17/km) + 1.5K cool-down
• Thursday: Easy run 8K
• Friday: Rest or core training
• Saturday: Easy run 6K (easy pace, saving energy for race day)
• Sunday: Long run 18K (first 15K easy, final 3K at goal pace)

Supplementary Strength Training

Building lower-body strength can significantly improve your ability to hold pace in the latter half of a half marathon:

• Calf raises: 3 sets × 20 reps, strengthening the calves and Achilles tendon
• Glute bridges: 3 sets × 15 reps, strengthening the glutes
• Single-leg squats: 2 sets × 10 reps, preventing knee valgus
• Plank: 60 seconds × 3 sets, strengthening core stability

Practical Tips

• Week 4’s “recovery week” is crucial—don’t skip the reduced volume just because you feel good. The recovery week allows your body to “digest” the training from the previous three weeks
• Across the full 8 weeks, you should complete at least one 10K test race or time trial to confirm your current fitness level
• Choosing a flat course (such as urban half marathons in Taichung or Kaohsiung) can make the Sub-2 goal easier to achieve
• If you experience abnormal pain in your lower limbs (beyond typical muscle soreness) during the plan, stop training immediately and consult a professional

Conclusion

Eight weeks of focused training is not magic—it is a process of allowing your body to adapt under the right stimuli. Stick to the plan, prioritize recovery, and stay confident before race day. That time hiding behind 2:00:00 will be waiting for you to break through at the finish line.

Related Reading

• Half-Marathon Sub-2 Training Plan: 12 Weeks from a 6:00/km Base to Breaking 2 Hours
• Breaking 2 Hours in the Half Marathon: A 14-Week Progression Targeting 5:40 Pace
• Sub-2 Half-Marathon Training: Pace, Milestones, and Key Workouts
• Half-Marathon Training Plan: 8-Week Race Preparation