Half Marathon Sub-1:45 Training Plan: A Dual-Track Approach to Speed and Lactate Tolerance

Introduction

A half marathon time of 1:45 (pace 4:58/km) is a highly respected achievement in the running community. In Taiwan, runners who can finish within this time rank in roughly the top 10–15% of finishers. This goal requires not just “running a lot,” but “running at the right intensities”—specifically, you need to improve both:

1. Lactate Threshold (allowing you to sustain a faster pace for longer)
2. Running Speed Reserve (making your target pace feel relatively comfortable)

This plan adopts a “dual-track” strategy, advancing both aspects simultaneously. It is suitable for runners whose current half marathon PB is between 1:50–2:00 and who run 45 km or more per week.

The Dual-Track Training Framework

Track 1: Lactate Threshold Improvement

Your lactate threshold pace is roughly the fastest speed you can sustain for 45–60 minutes. For a Sub-1:45 goal, this falls around 4:45–5:00/km.

Primary workout types:

• Tempo Run: 20–30 minutes continuous at LT pace (4:45–5:00/km)
• Cruise Intervals: 3–5 × 1.5 km at 4:45–4:50/km, with 1 minute easy recovery between reps

Track 2: Speed Reserve Improvement

Speed reserve refers to the gap between your maximum speed and your race pace. Improving your 5 km PB (e.g., from 22:00 to 20:00) will make the 4:58/km half marathon pace feel much easier.

Primary workout types:

• 400m Intervals: 8–12 × 400m at 4:20–4:30/km, with 90 seconds of easy jogging between reps
• 1000m Intervals: 5–6 × 1000m at 4:30–4:40/km, with 3 minutes of easy jogging between reps

14-Week Training Cycle

Key Pace Reference Table

Practical Advice

• Warm up thoroughly before intervals: At least 15 minutes of easy running plus dynamic stretching to reduce injury risk.
• Stop all high-intensity training one week before the race, doing only easy activation work.
• Race pace strategy: A “negative split” strategy is recommended—run the first half at 5:02/km, then gradually accelerate to 4:54/km in the second half. The feeling of speeding up in the latter half will give you a tremendous psychological advantage.
• Shoe selection: If your budget allows, wear carbon-plated racing shoes on race day. At a 4:58/km pace, good energy return can save approximately 3–4% of energy expenditure.

Conclusion

A Sub-1:45 half marathon requires runners to improve both speed and endurance simultaneously—not just “run more.” This 14-week dual-track plan, with its systematic intensity scheduling, lets you cross the finish line on race day with ample speed reserve and lactate tolerance. Taiwan offers many excellent racing environments; choose a winter or spring half marathon with moderate temperatures (10–18°C), and your Sub-1:45 is well within reach.

Related Reading

• Breaking 1:45 in the Half Marathon: Speed Breakthrough Strategies for Intermediate Runners
• Breaking 1:45 in the Half Marathon: A 16-Week Stacking of Threshold and Race Pace
• Breaking 1:45 in the Half Marathon: Lactate Threshold Training for Advanced Runners
• Training Leap from a 90-Minute to a 75-Minute Half Marathon: An Advanced 60K Weekly Plan