16-week marathon training plan

A 16-week marathon training plan takes a club runner on 45 km a week with a 1:55 half marathon from where they are to race day in 17 weeks, building to 79 km in the biggest week. It spends 6 weeks in base, 6 weeks in build, 2 weeks in peak, 2 weeks in taper, with 3 lighter weeks to absorb the work, on 6 days a week.

Build my marathon plan — free

Built from your own numbers and your own week. The first week is free.

Is 16 weeks enough?

16 weeks is a comfortable length for a marathon. There is room for a proper base before the harder work, lighter weeks to absorb it, and a taper that leaves you fresh rather than flat.

What the weeks are for

Base	6 weeks — aerobic volume, mostly easy, the foundation everything else stands on
Build	6 weeks — the harder sessions arrive and volume keeps climbing
Peak	2 weeks — the biggest, most race-specific weeks
Taper	2 weeks — volume drops, intensity stays, you arrive fresh
Lighter weeks	3, roughly every fourth week
Total	983 km, 129 hours

The 17 weeks

Generated for a club runner on 45 km a week with a 1:55 half marathon.

Week	Phase	Volume	Load
1	Base	45 km	258
2	Base	49 km	282
3	Base	53 km	301
4	Base · down	36 km	214
5	Base	57 km	320
6	Base	61 km	343
7	Build	60 km	368
8	Build · down	44 km	261
9	Build	65 km	390
10	Build	69 km	409
11	Build	72 km	431
12	Build · down	52 km	305
13	Peak	76 km	444
14	Peak	79 km	459
15	Taper	66 km	375
16	Taper	51 km	292
17	Race · race	47 km	407

The biggest week, session by session

Week 14, peak phase — the heaviest week of the block.

Monday	Easy run — 1h12, 10.4 km
Tuesday	Threshold — 2 × 10 min — 0h54, 8.1 km
Tuesday	Strength — lower body — 0h27
Wednesday	Easy run — 1h12, 10.4 km
Friday	Race pace — 9 km — 1h12, 11.4 km
Saturday	Easy run — 1h12, 10.4 km
Sunday	Long run with a fast finish — 3h00, 28.1 km

The paces

Pace band	Per kilometre
Easy — the ceiling, not the target	6:19
Marathon pace	5:41
Threshold	5:22
Interval (VO₂max)	4:51

Computed from VDOT 38.3, derived from that time trial using Jack Daniels' model. Your own numbers will differ — the plan builds these from a time trial you enter.

What this plan says out loud

Worth knowing

Some sessions have been cut to fit the time you said you have — 75 minutes on a weekday and 180 at the weekend. That is a real constraint and the plan respects it, but be aware the long session is the one that matters most: if you can find more time anywhere, find it on the weekend.

Worth knowing

On 6 days a week there is nowhere to put 34 km without prescribing runs nobody should be doing. The plan caps individual easy runs at 14 km and carries less volume than your target as a result. More days would do more for you than longer runs.

Worth knowing

Race day looks like about 3:57:48 on today's fitness — Run 3h 58. Assumes a flat course, reasonable conditions and a sensible first half.

Common questions

Is 16 weeks enough for a marathon?

Yes, for most people who already exercise. We would choose at least 16 weeks, and this is 16.

How many days a week does it train?

6, on Monday, Tuesday, Wednesday, Friday, Saturday, Sunday in this example. You tell the plan which days you actually have, and it never puts two hard days back to back.

What is the longest session?

Long run with a fast finish, about 3h00 and 28 km. It is capped by share of the week, by absolute length, and by the time you say you have.

Can I use this if I train at altitude?

Yes, and you should say so when you build it. Paces and power are corrected for the difference between where you tested and where you train — in Johannesburg that is roughly 8%, or about 26 seconds a kilometre on an easy run for a 20-minute 5 km runner.

16-week marathon training plan

What the weeks are for

The 17 weeks

The biggest week, session by session

The paces

What this plan says out loud

Common questions

Other marathon plans

Goal times

South African races at this distance

Worth reading