Marathon PB Three-Core Plan
Convert from a marathon or half-marathon PB, then generate a 12 / 16 / 20 week schedule
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Three-core training paces
🔴 Speed endurance · PB − 10 sec/km
5:31/km
1× / week · Build sustained speed above marathon pace. Standard sets: 3 km × 2, 2 km × 3, 1 km × 6.
🔵 LSD · PB + 50 sec/km
6:31/km
1× / week · Typical week 21–25 km to build aerobic endurance for the second half of the marathon.
Long LSD：25–30 km on a monthly key long-run week.
🟢 Recovery run · PB + 60–120 sec/km
6:41–7:41/km
As needed · Stay in Z2. Do not chase pace. Nasal breathing is a useful intensity check; slow down if tired.
Each week: 1 speed-endurance session + 1 LSD, with recovery runs or rest on other days.
16-week PB plan
Cycle overview
Base
Build
Peak
Taper
Race week
| Week |
Phase |
LSD |
Est. km |
| 1 |
Base
|
18
km
|
49
km
|
| 2 |
Base
|
20
km
|
50
km
|
| 3 |
Base
|
21
km
|
51
km
|
| 4 |
Base
Long LSD
|
24
km
|
55
km
|
| 5 |
Build
Recovery week
|
18
km
|
50
km
|
| 6 |
Build
|
22
km
|
60
km
|
| 7 |
Build
|
24
km
|
62
km
|
| 8 |
Build
Long LSD
|
27
km
|
65
km
|
| 9 |
Peak
Recovery week
|
20
km
|
62
km
|
| 10 |
Peak
|
24
km
|
74
km
|
| 11 |
Peak
|
25
km
|
75
km
|
| 12 |
Peak
Long LSD
|
30
km
|
80
km
|
| 13 |
Peak
|
24
km
|
74
km
|
| 14 |
Taper
|
18
km
|
48
km
|
| 15 |
Taper
|
12
km
|
42
km
|
| 16 |
Race week
|
8
km
|
63.2
km
|
Week 1 · Base
Build aerobic base with reduced speed-endurance volume.
About 49 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
3 km × 1 + 2 km × 1 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 6 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Rest
Rest, or an easy recovery run if you feel fresh
Sleep, stretch, and eat well. Skip training if you feel worn down.
LSD
LSD 18 km @ 6:31/km
Keep it easy and aerobic. Adjust within the suggested range based on recovery.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 2 · Base
Build aerobic base with reduced speed-endurance volume.
About 50 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
2 km × 2 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 6 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Rest
Rest, or an easy recovery run if you feel fresh
Sleep, stretch, and eat well. Skip training if you feel worn down.
LSD
LSD 20 km @ 6:31/km
Keep it easy and aerobic. Adjust within the suggested range based on recovery.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 3 · Base
Build aerobic base with reduced speed-endurance volume.
About 51 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
1 km × 4 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 6 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Rest
Rest, or an easy recovery run if you feel fresh
Sleep, stretch, and eat well. Skip training if you feel worn down.
LSD
LSD 21 km @ 6:31/km
Keep it easy and aerobic. Adjust within the suggested range based on recovery.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 4 · Base
Build aerobic base with reduced speed-endurance volume.
Long LSD About 55 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
3 km × 1 + 2 km × 1 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 6 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Rest
Rest, or an easy recovery run if you feel fresh
Sleep, stretch, and eat well. Skip training if you feel worn down.
Long LSD
Long LSD 24 km @ 6:31/km
Optional: last 6 km at PB pace 5:41/km. Stay at LSD pace if it feels too hard.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 5 · Build
Increase mileage and use full speed-endurance sets. LSD moves into 21–25K.
Recovery week About 50 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
2 km × 3 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 6 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Rest
Rest, or an easy recovery run if you feel fresh
Sleep, stretch, and eat well. Skip training if you feel worn down.
LSD
LSD 18 km @ 6:31/km
Keep it easy and aerobic. Adjust within the suggested range based on recovery.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 6 · Build
Increase mileage and use full speed-endurance sets. LSD moves into 21–25K.
About 60 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
1 km × 6 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Rest
Rest, or an easy recovery run if you feel fresh
Sleep, stretch, and eat well. Skip training if you feel worn down.
LSD
LSD 22 km @ 6:31/km
Keep it easy and aerobic. Adjust within the suggested range based on recovery.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 7 · Build
Increase mileage and use full speed-endurance sets. LSD moves into 21–25K.
About 62 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
3 km × 2 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Rest
Rest, or an easy recovery run if you feel fresh
Sleep, stretch, and eat well. Skip training if you feel worn down.
LSD
LSD 24 km @ 6:31/km
Keep it easy and aerobic. Adjust within the suggested range based on recovery.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 8 · Build
Increase mileage and use full speed-endurance sets. LSD moves into 21–25K.
Long LSD About 65 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
2 km × 3 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Rest
Rest, or an easy recovery run if you feel fresh
Sleep, stretch, and eat well. Skip training if you feel worn down.
Long LSD
Long LSD 27 km @ 6:31/km
Optional: last 6 km at PB pace 5:41/km. Stay at LSD pace if it feels too hard.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 9 · Peak
Highest load, including 25–30K long LSD sessions.
Recovery week About 62 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
1 km × 6 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 6 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
LSD
LSD 20 km @ 6:31/km
Keep it easy and aerobic. Adjust within the suggested range based on recovery.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 10 · Peak
Highest load, including 25–30K long LSD sessions.
About 74 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
3 km × 2 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
LSD
LSD 24 km @ 6:31/km
Keep it easy and aerobic. Adjust within the suggested range based on recovery.
Recovery
Recovery 12 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 11 · Peak
Highest load, including 25–30K long LSD sessions.
About 75 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
2 km × 3 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
LSD
LSD 25 km @ 6:31/km
Keep it easy and aerobic. Adjust within the suggested range based on recovery.
Recovery
Recovery 12 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 12 · Peak
Highest load, including 25–30K long LSD sessions.
Long LSD About 80 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
1 km × 6 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Long LSD
Long LSD 30 km @ 6:31/km
Optional: last 6 km at PB pace 5:41/km. Stay at LSD pace if it feels too hard.
Recovery
Recovery 12 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 13 · Peak
Highest load, including 25–30K long LSD sessions.
About 74 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
3 km × 2 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 10 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
LSD
LSD 24 km @ 6:31/km
Keep it easy and aerobic. Adjust within the suggested range based on recovery.
Recovery
Recovery 12 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 14 · Taper
Cut volume, keep some pace work, and absorb training.
About 48 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
2 km × 2 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 6 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Rest
Rest, or an easy recovery run if you feel fresh
Sleep, stretch, and eat well. Skip training if you feel worn down.
LSD
LSD 18 km @ 6:31/km
Keep it easy and aerobic. Adjust within the suggested range based on recovery.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 15 · Taper
Cut volume, keep some pace work, and absorb training.
About 42 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Speed endurance
1 km × 4 @ 5:31/km
About 2 km warm-up / cool-down each (6:41/km). 3 minutes rest between reps.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 6 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Rest
Rest, or an easy recovery run if you feel fresh
Sleep, stretch, and eat well. Skip training if you feel worn down.
LSD
LSD 12 km @ 6:31/km
Keep it easy and aerobic. Adjust within the suggested range based on recovery.
Recovery
Recovery 8 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Week 16 · Race week
Rest and easy running, then race at PB pace.
About 63.2 km this week
Rest
Full rest
Sleep, stretch, and eat well. Skip training if you feel worn down.
Shakeout
Easy 5 km @ 6:41/km + 4×100 m strides
Keep the legs fresh. Do not chase speed.
Recovery
Recovery 5 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Recovery
Recovery 5 km @ 6:41–7:41/km
Z2 only. Do not chase pace; slow down further if tired.
Rest
Rest, or an easy recovery run if you feel fresh
Sleep, stretch, and eat well. Skip training if you feel worn down.
Shakeout
Shakeout 5 km @ 6:41/km
Very easy, short, just to check how the body feels.
Race
Race day 42.195 km @ 5:41/km
Start at PB pace, stay conservative early, then decide in the second half.
Three-core rules and periodization
- Speed endurance: PB pace minus 10 sec/km, once a week, 3 minutes rest. Rotate 3 km × 2, 2 km × 3, 1 km × 6.
- LSD: PB pace plus 50 sec/km, once a week. Typical 21–25 km, with one 25–30 km long LSD each month.
- Recovery: PB pace plus 60–120 sec/km in Z2. Default week: Mon rest, Tue speed, Wed/Thu recovery, Fri rest or easy, Sat LSD, Sun recovery.
- The full plan adds load/recovery weeks, long-run periodization and a taper into race day.
- Half conversion: T2 = T1 × (D2 / D1)^1.06. If you enter a half PB, it is converted to an equivalent marathon before calculating training paces.
Notes
- This is a programmed version of the PB three-core model. It is a training framework, not medical or 1-on-1 coaching advice.
- Adjust distance to your current weekly mileage, training age and recovery. Rest when the body warns you.
- If you enter a half PB, it is first converted to an equivalent marathon. Use a finished result, not an untested goal time.