Half Marathon Training Guide

How to Run a Sub-1:45 Half Marathon

Running a half marathon in under 1 hour 45 minutes requires averaging about 5:00 per kilometer - a pace that demands both speed and endurance. This is a popular goal for experienced runners looking to push their limits.

Pace /km

4:58

Pace /mile

8:00

Speed

12.1 km/h

What are the prerequisites to run a 1:45:00 Half Marathon?

1

10K Time Trial

Under 48 minutes indicates sub-1:45 half fitness

2

3×3K Repeats

Complete each rep at 4:50-4:55/km pace

3

Weekly Mileage

45-60 km per week for at least 8 weeks

Key Training Principles

Follow these principles to build the fitness needed for your goal.

Build Mileage Gradually

Target 45-60 km per week. Increase by no more than 10% weekly.

Example: Build from 45 km to 55-60 km over 8-10 weeks

Include Intervals

One quality speed session per week at faster than race pace.

Example: 6×1km at 4:40-4:45/km with 2-3 minutes recovery

Add Tempo Runs

Run at race pace or slightly slower to build lactate threshold.

Example: 35-45 minutes at 5:05-5:10/km pace

Long Runs with Pace Work

Build to 18-22 km, sometimes including race-pace segments.

Example: 18 km with final 6 km at goal pace

Strength Work

Regular strength training improves running economy.

Example: Squats, lunges, core work - 2x per week for 20 minutes

Sample Training Week

Here is what a typical training week might look like.

DayWorkout
MondayRest
TuesdayIntervals
WednesdayEasy Run
ThursdayTempo Run
FridayEasy Run + Strength
SaturdayLong Run
SundayEasy Run

Want a personalized training plan tailored to your schedule and fitness level?

Race Day Strategy

Follow this race day execution plan to hit your goal.

  1. 1

    Warm up with 10-15 minutes easy jogging, dynamic drills, and strides

  2. 2

    Start at goal pace (4:58/km) - first 5K should feel controlled

  3. 3

    Hit 10K at around 50 minutes, halfway at 52:30

  4. 4

    Take gels at planned intervals and practice this in training

  5. 5

    Kilometers 15-18 require mental toughness - stay focused on form

  6. 6

    Final 5K: commit to maintaining pace and push hard to the line

Common Mistakes to Avoid

  • Going out at 4:45/km and struggling in the second half
  • Not enough long runs with race-pace segments
  • Insufficient total weekly mileage
  • Neglecting fueling strategy
  • Running too hard in the days before the race

Frequently Asked Questions

Yes, a 1:45 half marathon is a very good time. It places you well ahead of the average finisher and demonstrates strong speed-endurance ability.

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