Training plans Marathon
The sub-3:45 marathon
To break 3:45 for the marathon, you need an average of 5:20 per kilometre — 8:35 per mile — from gun to tape. Most runners get there on 60–83km per week across 4–5 runs, built over roughly 15–19 weeks. Expect three gears in the plan: 6:15–6:50/km for easy runs, roughly 4:57/km for tempo sessions, and 4:42/km for intervals. Your starting fitness decides whether the goal is a season away or further — judge it from a recent race, not a hopeful guess.
Last updated 2026-07-03 · paces computed, not copywritten
Goal pace
5:20/km
8:35/mi
Typical build
15–19 weeks
60–83 km/week
Runs per week
4–5
3 key sessions + easy volume
Required paces
| SESSION | PACE (/KM) |
|---|---|
| Easy runs | 6:15–6:50 |
| Long run | 5:45–6:15 |
| Tempo | 4:57 |
| Intervals | 4:42 |
| Race pace | 5:20 |
Splits at goal pace
| CHECKPOINT | CLOCK |
|---|---|
| 10K | 53:19 |
| Half | 1:52:30 |
| 30K | 2:39:58 |
| Finish | 3:45:00 |
The table assumes level pacing; most runners land a 3:45 by holding two or three seconds per kilometre back from 5:20 early on.
A typical week
Key session 1
Intervals — reps around 4:42/km (5K effort) with jog recoveries
Key session 2
Tempo — sustained comfortably-hard running near 4:57/km
Long run
The week's cornerstone at 5:45–6:15/km, adding 3:45-pace finishes as race day nears
Plus 2+ easy runs. Everything else is easy running at 6:15–6:50/km — the volume that makes the hard days land.
Asked often
- What pace is a sub-3:45 marathon?
- 5:20 per kilometre, held for the full marathon. The runners who break 3:45 are usually the ones still passing people in the last quarter.
- How long should I train for a sub-3:45 marathon?
- From a reasonable base, 15–19 weeks. If you're returning from a break, rebuild first — squeezing a 15-week plan into less is how marathon builds break.
- What happens if I miss training weeks?
- If the plan can't adjust, missed weeks turn into injury risk or a blown goal. RunV recalibrates after every run — including the ones that didn't happen — to keep 3:45 in reach.
This fitness at other distances
- Half marathon: 1:47:55 equivalent
- 10K: 48:55 equivalent
- 5K: 23:28 equivalent
Sub-3:45, minus the guesswork
RunV builds your sub-3:45 plan around your week, then recalibrates it after every run — finished, cut short, or missed.
