Running program
12-week half-marathon training plan for intermediate runners
An intermediate four-day plan with easy, tempo, interval, and long runs, building the long run to 18 km before race week.
- Days / week
- 4
- Block length
- 12 weeks
- Cost
- Free
Your numbers
This program is prescribed by effort rather than percentages, so there is nothing to calculate — the week below is ready to run.
The week
Easy run
- Easy run45 mineasy effort
Intervals
- Interval run5 × 1 km10 km effort
Rest
Tempo run
- Tempo run30 minhalf-marathon effort
Rest
Long run
- Long run16 kmeasy effort
Rest
The week adds up to
- Sessions
- 4
- Working sets
- 0
- Rest days
- 3
Choose your start day
The coach can fit the four runs around your week, set paces from a recent result, and adjust the build from what you log.
Who this half-marathon plan is for
This plan fits runners who already manage about 25–35 km per week and can comfortably run 10 km. Twelve weeks is enough to build specificity, but not to create a running base from zero; newer runners should establish that base first.
How the week balances quality and distance
Intervals develop speed above race effort, tempo running makes sustained work familiar, and the long run extends durability. Easy running connects those sessions without turning every day into a test. Three recovery days keep quality separated.
How the long run reaches 18 km
Build the long run in small steps, use every third or fourth week as a reduction, and peak at 18 km before tapering. Increase either distance or intensity in a week, not both. Practice the fuel and kit you will use on race day.
If fatigue starts accumulating
Remove interval volume first while keeping easy frequency. If normal easy pace feels hard for several days, take an extra rest day and resume at the previous week's distance. Consistency across twelve weeks matters more than completing one heroic session.
How to move sessions
Keep at least one easy or rest day between intervals, tempo, and the long run. A bike or pool session can replace an easy run when impact is the problem, but it should not replace the long run that prepares your legs for the distance.
This is a training template, not medical advice. Loads are starting points, not prescriptions — scale them to your own experience, and talk to a qualified clinician before starting a new program if you have an injury or a health condition.