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RunThreshold

Norwegian 25 × 400

25 × 400 m at controlled threshold, 30 s rest

Time
≈1h21
Hard
≈43:17
in zones 4–5
Difficulty
Very hardDifficulty 4 of 5 — Very hard
Inspired by
Ingebrigtsen brothers

What we typed

Warm up 15 min easy. 25 × (400 m at controlled threshold effort, about 10K effort; 30 s rest). Cool down 10 min easy.

Fit File Forge built the steps below from these words — the same steps your watch gets.

Describe your own

The session

4 steps

Warm up

easy

15 minZ2
25×400 m

Rep

controlled threshold effort, about 10K effort

400 mZ4

Rest

30 secZ1

Cool down

easy

10 minZ1

Targets

Set by race effort. Your paces follow from your threshold pace — about what you could race for an hour.

Threshold effort

Save it and race efforts become your own paces, from your profile or your Garmin training. Without them every rep keeps its effort cue.

Scaled version

12–15 × 400 m with 30–45 seconds' rest.

Build the scaled version in Forge

About this session

The story

An evening session from the sample week of the 'Norwegian model' — the double-threshold approach whose best-known proponents are the Ingebrigtsen brothers: 25 × 400 m at a controlled threshold intensity with 30 seconds' recovery. It's the model's session, not a documented Jakob Ingebrigtsen workout.

What it trains

Threshold volume at a quick rhythm: the short reps let you run faster than a tempo while staying under your lactate turn-point.

Who it's for

Well-trained 1500 m to 10K runners. Most athletes should start far below 25 reps.

Sources 1
  1. How the "Norwegian Method" Is Changing Endurance Training — Outside, 2023

I've been using the AI Training Coach from day 1 for marathon prep and have found it to be a huge step up from ChatGPT/Gemini — I couldn't be happier.

Dave F.Marathon athlete

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