21 km Long Run With a Marathon Pace Kilometer Every 3 km
A 21 km long run where every third kilometer is at marathon pace, six in total, to practice finding race rhythm from easy running again and again.
- Duration
- 1 h 53 minestimated
- Distance
- 21 kmestimated
- Effort
- 132
- Level
- Intermediate
- Focus zone
- Endurance
Your values
Targets relative to your threshold values. Enter your values to see absolute numbers.
100% is your threshold pace. Higher values are faster, lower values are slower.
| # | Step | Length | Target |
|---|---|---|---|
| 1 | Warm-upRecovery Very easy 2 km | 2000 m | 70-78% threshold pace55-68% HRmax60-72% FTP |
| 6 ×Repeat these steps | |||
| 2.1 | IntervalEndurance 2 km easy aerobic | 2000 m | 78-88% threshold pace68-78% HRmax72-82% FTP |
| 2.2 | IntervalTempo 1 km at marathon pace | 1000 m | 89-93% threshold pace78-86% HRmax82-89% FTP |
| 3 | Cool-downRecovery Easy jog | 1000 m | 70-78% threshold pace55-68% HRmax60-72% FTP |
About this workout
This long run stays mostly easy but brings in marathon pace again and again. After a 2 km warm-up, you run 2 km easy and 1 km at marathon pace, six times, before an easy final kilometer. Six kilometers at goal pace add up to a solid dose, and each one starts from relaxed running, which trains you to find race rhythm quickly and drop back to easy without stopping.
Run 2 km very easily. Then alternate 2 km at an easy aerobic effort with 1 km at goal marathon pace, six times. Finish with 1 km of easy jogging. Make each change smooth, using the first 100 m to settle into the new pace. The easy sections should feel truly easy, so the last marathon pace kilometer is as controlled as the first.
This suits intermediate and advanced marathoners in the early specific phase, as a step before long runs with continuous marathon pace blocks. It also works for half marathoners as a long run with some rhythm.
Tips
- Aim for the same split on every marathon pace kilometer.
- Take a drink in the easy sections.
- Keep the easy kilometers at your normal easy pace, not faster.
Good forMarathonHalf marathon
Season phaseBuild