Cardio and running
Marathon Training Plan: 16 Weeks for Your First Marathon
Published October 20, 2026
A first marathon takes about 16 weeks of training if you already run three times a week and have finished a half marathon or a 90-minute run. The plan rests on four pillars: mostly easy running, one long run per week building to 18-20 miles (29-32 km) or about 3 hours, marathon-pace blocks, and a 2-3 week taper.
Prerequisites
| Prerequisite | Why |
|---|---|
| 6+ months of consistent running | Tendons and bones adapted |
| 15-20 miles (25-30 km) per week pain-free | Base for the plan |
| A 90-minute continuous run | Starting point for long runs |
| A recent 10K or half time | To set marathon pace |
Picking a goal time
A study of thousands of recreational runners found common prediction formulas often overestimate marathon performance; the best predictors combined a shorter race time with training volume (Vickers & Vertosick, 2016). Be conservative: a first marathon is about finishing strong.
| Goal | Pace per mile | Pace per km |
|---|---|---|
| 3:30 | 8:01 | 4:58 |
| 4:00 | 9:09 | 5:41 |
| 4:30 | 10:18 | 6:24 |
| 5:00 | 11:27 | 7:07 |
The 16-week plan
E = easy; MP = marathon pace; LR = long run.
| Wk | Tue | Thu | Fri | Sun (LR) |
|---|---|---|---|---|
| 1 | 5 mi E | 8 × 1 min fast | 4 mi E | 9 mi |
| 2 | 5 mi E | 3 × 1 mi MP | 4 mi E | 10 mi |
| 3 | 6 mi E | 6 × 1 km at 10K pace | 4 mi E | 11 mi |
| 4 | 4 mi E | 2 × 2 mi MP | 3 mi E | 9 mi (cutback) |
| 5 | 6 mi E | 3 × 2 mi MP | 5 mi E | 12 mi |
| 6 | 6 mi E | 8 × 1 km | 5 mi E | 13 mi, last 3 at MP |
| 7 | 7 mi E | 2 × 3 mi MP | 5 mi E | 14 mi |
| 8 | 5 mi E | 6 × 1 km | 4 mi E | Half-marathon race or time trial |
| 9 | 7 mi E | 3 × 3 mi MP | 6 mi E | 15 mi, 5 at MP |
| 10 | 7 mi E | 10 × 800 m | 6 mi E | 16 mi |
| 11 | 7 mi E | 2 × 4 mi MP | 6 mi E | 18 mi, 6 at MP |
| 12 | 5 mi E | 6 × 1 km | 4 mi E | 13 mi (cutback) |
| 13 | 7 mi E | 3 × 3 mi MP | 6 mi E | 20 mi (longest) |
| 14 | 6 mi E | 2 × 3 mi MP | 5 mi E | 14 mi, 5 at MP |
| 15 | 5 mi E | 3 × 1.5 mi MP | 4 mi E | 10 mi |
| 16 | 4 mi E | 3 mi E + strides | Rest | Race |
Most of the volume stays easy, the pattern seen in successful endurance athletes (Seiler, 2010). Easy pace explained: zone 2 cardio.
Fueling
- Practice drinking and eating carbs during long runs (gels, chews, sports drink).
- Race day: drink at aid stations and take carbs regularly from the first hour.
- Nothing new on race day: shoes, gels or breakfast.
Strength training
Two 20-minute sessions a week (squats, lunges, calf raises, core). Strength training improves running economy (Blagrove et al., 2017); see strength training for runners.
Warning signs
| Sign | Response |
|---|---|
| Pain that worsens during a run | Stop, rest, see a professional if it persists |
| Resting heart rate up 5-10 bpm for days | Take a cutback week |
| Poor sleep, constant fatigue | Drop a workout |
Over 40 and new to endurance training, or any heart condition: get a medical check before starting. Shorter goal first? Half marathon training plan.