A half marathon training plan bridges the gap between shorter races and the full marathon. At 21.1 kilometres, the half marathon is challenging enough to require dedicated training but manageable enough to fit into most schedules without overwhelming your life.
Half marathons have become increasingly popular worldwide, offering runners a meaningful goal that doesn't require the extreme time commitment of marathon training. Whether this is your first half marathon or you're aiming for a new personal best, a structured 12-week plan can get you to the finish line feeling strong.
Building Your Base
Before starting a half marathon plan, you should be able to run comfortably for 30-40 minutes. The base phase establishes aerobic fitness and prepares your body for higher training loads.
- 3-4 easy runs per week (30-50 minutes)
- 1 long run on weekends (starting at 8-10 km)
- 1-2 strength or mobility sessions
- At least 1 full rest day
The Build Phase
This is where you develop speed and endurance. Weekly mileage increases gradually, and you introduce quality sessions that make you faster and more efficient.
- Tempo runs (20-30 minutes at comfortably hard pace)
- Interval sessions (6-8 x 400-800m at 5K pace)
- Long runs progressing to 16-18 km
- Easy recovery runs between hard efforts
Peak Week and Taper
The final two weeks before race day reduce volume while maintaining intensity. Your longest run should be 2-3 weeks before the race, giving your body time to recover and absorb the training.
- Peak long run of 18-19 km (2-3 weeks before race)
- Reduce mileage to 60-70% in final two weeks
- Keep one short tempo or interval session to stay sharp
- Prioritise sleep, hydration, and nutrition
Strength and Cross-Training
Running-specific strength work makes you more resilient and efficient. Focus on exercises that support running mechanics rather than building bulk.
Two 20-30 minute strength sessions per week are sufficient. Target glutes, hamstrings, calves, and core. Single-leg exercises like split squats and step-ups are particularly effective for runners.
Swimming, cycling, or using an elliptical once weekly can boost cardiovascular fitness while giving your joints a break from impact.
Common Training Mistakes
- Running too fast on easy days: Most training should feel comfortable, not exhausting.
- Increasing mileage too quickly: Stick to 10% weekly increases to avoid injury.
- Skipping recovery: Adaptation happens during rest, not during the workout itself.
- Neglecting nutrition: Underfueling leads to fatigue, poor performance, and injury risk.
- Racing every training run: Save your competitive energy for quality sessions and race day.
Example 12-Week Half Marathon Training Plan
| Phase | Focus | Weekly Mileage | Long Run | Key Sessions |
|---|---|---|---|---|
| Weeks 1-3 | Base Building | 25-35 km | 8-12 km | Easy runs + strength |
| Weeks 4-8 | Build | 35-50 km | 13-18 km | Tempo runs, intervals |
| Weeks 9-10 | Peak | 45-55 km | 18-19 km | Race-pace runs |
| Weeks 11-12 | Taper | 25-35 km | 10-13 km | Short tempo + rest |
Race Day Strategy
Start conservatively. The first 5 kilometres should feel easy, almost too easy. Most runners go out too fast and suffer in the final kilometres. Aim to run the second half at the same pace or slightly faster than the first half (negative split).
Practice your race-day nutrition during training. Most runners need water every 3-5 km and can benefit from an energy gel or chew around the 10 km mark.
After the Race
Take at least one full week off running after the race. Light walking and swimming are fine, but your body needs recovery time. Return gradually with easy runs for another week before resuming normal training.
If you enjoyed the distance, consider running another half marathon in 8-12 weeks, or progress toward a full marathon if you're ready for the challenge.
Make Training Simpler
Following a structured plan week after week requires organisation and consistency. Whether you're training solo or coaching others through their half marathon journey, tools like Motifind help you build training programs, track progress, and stay accountable without relying on spreadsheets or manual tracking.