Training 7 min
1:45 half marathon
A 1:45 half marathon is a sub-8-minute-mile average pace—achievable with structured training, disciplined tempo work, and cumulative aerobic fitness. Most runners can reach this target within 12–16 weeks if they have a base of 20–25 miles per week and follow a plan built around speed sessions and progression.
What pace do you need to run?
A 1:45 half marathon demands a consistent 7:56 per mile (or 4:56 per kilometre). On undulating courses or in wind, you'll need to push slightly harder on climbs and recover on descents. Even splits or negative splits (running the second half faster) are the ideal race strategy.
Build a realistic training base
Before starting a 1:45 plan, you should comfortably run 20–25 miles per week for at least 4–6 weeks. This foundation prevents injury and allows you to handle the intensity ahead. If you're currently at 15 miles per week, spend 3–4 weeks building up gradually.
Key workouts to target 1:45
- Tempo runs: 20–30 minutes at 7:30–7:40 pace, once a week, to build lactate threshold
- Race-pace repeats: 4–6 × 1 mile at 7:56 pace with 90 seconds recovery, fortnightly
- Long runs: Build to 11–12 miles at 8:30–9:00 pace to develop aerobic capacity and mental toughness
- Easy runs: 3–4 runs per week at 8:30–9:15 pace for recovery and volume
- Hill or fartlek sessions: Once every 10–14 days to build strength and run economy
Structure a 12–16 week training block
- Weeks 1–4 (base phase): establish 25–30 miles per week, introduce tempo runs at 7:45 pace, long run to 9 miles
- Weeks 5–8 (build phase): increase to 30–35 miles per week, sharpen with race-pace repeats, long run to 11 miles
- Weeks 9–11 (peak phase): hold 32–35 miles per week, run final race-pace sessions, reduce long run volume slightly
- Week 12–16 (taper and race): drop mileage by 10–20% each week leading to race, reduce run frequency but maintain pace
Recovery and adaptation matter as much as hard work
Hitting 1:45 depends equally on recovery quality. Sleep 7–9 hours, eat a carbohydrate-rich diet, and take one full rest day per week. Running hard twice a week is plenty; additional sessions should be easy or mobility-focused.
Pacing strategy for race day
Start conservatively in the first mile (aim for 8:05–8:10). Settle into 7:55–7:58 pace for miles 2–10. In the final 3 miles, if you feel strong, push to 7:50–7:55. If fatigue sets in, maintain 7:56 to secure the time.
Use data and feedback to refine your plan
Monitor your progress weekly: track heart rate zones, how each session feels, and recovery metrics like resting heart rate. A data-driven approach—like the analysis available in RunV—lets you adjust intensity and volume in real time. If a tempo run feels flat or a long run drains you for days, dial back the next session rather than pushing through. Conversely, if you're consistently hitting paces with ease, gradually increase the challenge. This adaptive method ensures you arrive at the race line fresh and confident, not burnt out.
FAQ
- Can I reach 1:45 on four runs per week?
- Yes, but it's tight. You'll need one long run (11–12 miles), one tempo session (20–30 min), one race-pace repeat workout, and one easy run. Cross-training or a short fifth run helps, but quality over quantity is the rule.
- What if I've only run a 1:55 half marathon before?
- A 10-minute improvement is realistic over 16 weeks if you follow a structured plan and stay injury-free. Focus on consistent tempo and race-pace work, not just long runs. Expect progress to plateau; breaking 1:45 requires specific adaptation to faster paces.
- How do I know if I'm ready to start a 1:45 plan?
- You should comfortably run a 5K at around 24:30–25:00 and be averaging 20–25 miles per week without injury niggles. If you can't yet sustain 8-minute pace for a full easy run, give yourself 4–6 more weeks of base building.
Train smarter
RunV turns this thinking into your plan — adaptive coaching that rebuilds after every run.
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